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a novel glucose biosensor using bi-enzyme incorporated with peptide nanotubes.a novel amperometric glucose biosensor was developed using the bio-inspired peptide nanotube (pnt) as an encapsulation template for enzymes. horseradish peroxidase (hrp) was encapsulated by the pnt and glucose oxidase (go(x)) was co-immobilized with the pnt on a gold nanoparticle (aunp)-modified electrode. a binary sam of 3-mercaptopropionic acid (mpa) and 1-tetradecanethiol (tdt) was formed on the surface of the electrode to immobilize the pnt and go(x). the resulting electrode appeared to prov ...201222763144
amperometric bienzymatic biosensor for l-lactate analysis in wine and beer samples.a novel amperometric bienzymatic biosensor has been developed based on the incorporation of lactate oxidase (lox) and horseradish peroxidase (hrp) into a carbon nanotube/polysulfone membrane by the phase inversion technique onto screen-printed electrodes (spes). in order to improve the sensitivity and reduce the working potential, experimental conditions have been optimized and ferrocene has also been incorporated into the membrane as a redox mediator of the enzymatic reactions, which allows the ...201222763889
photooxidation of amplex red to resorufin: implications of exposing the amplex red assay to light.the amplex red assay, a fluorescent assay for the detection of h(2)o(2), relies on the reaction of h(2)o(2) and colorless, nonfluorescent amplex red with a 1:1 stoichiometry to form colored, fluorescent resorufin, catalyzed by horseradish peroxidase (hrp). we have found that resorufin is artifactually formed when amplex red is exposed to light. in the absence of h(2)o(2) and hrp, the absorption and fluorescence spectra of amplex red changed during exposure to ambient room light or instrumental e ...201222765927
recognition-driven layer-by-layer construction of multiprotein assemblies on surfaces: a biomolecular toolkit for building up chemoresponsive bioelectrochemical interfaces.the development of soft bioelectronic interfaces with accurate compositional and topological control of the supramolecular architecture attracts intense interest in the fast-growing field of bioelectronics and biosensing. the present study explores the recognition-driven layer-by-layer assembly of glycoenzymes onto electrode surfaces. the design of the multi-protein interfacial architecture is based on the multivalent supramolecular carbohydrate-lectin interactions between redox glycoproteins an ...201222766969
disposable amperometric magneto-immunosensor for direct detection of tetracyclines antibiotics residues in milk.the preparation and performance of a disposable amperometric magneto-immunosensor, involving the use of a selective capture antibody immobilized on the surface of protein g-functionalized magnetic beads (protg-mbs) and screen-printed carbon electrodes (spces), for the specific detection and quantification of tetracyclines (tcs) residues in milk is reported. a direct competitive immunoassay using a tracer with horseradish peroxidase (hrp) for the enzymatic labeling was performed. the amperometric ...201222769033
wrapping tissues with a pre-established cage-like layer composed of living cells.we report a method for wrapping tissues with a pre-established cage-like layer composed of living cells. we encapsulated multicellular aggregates of human hepatoma hepg2 cells as a model of tissues such as pancreatic islets and hepatocyte spheroids in alginate-based hydrogel microcapsules and subsequently coated the microcapsule surface with a gelatin derivative through a horseradish peroxidase-catalyzed reaction. human aorta endothelial (hae) cells grew on the surface and formed a cell layer wi ...201222770525
gold-fish: a new approach for the in situ detection of single microbial cells combining fluorescence and scanning electron microscopy.a novel fluorescence in situ hybridisation (fish) method is presented that allows the combination of epifluorescence and scanning electron microscopy (sem) to identify single microbial cells. first, the rrna of whole cells is hybridised with horseradish peroxidase-labelled oligonucleotide probes and this is followed by catalysed reporter deposition (card) of biotinylated tyramides. this facilitates an amplification of binding sites for streptavidin conjugates covalently labelled with both fluoro ...201222770611
a disposable electrochemical immunosensor based on carbon screen-printed electrodes for the detection of prostate specific antigen.a novel screen-printed electrode (spes) on sheets of vegetable parchment was prepared. the obtained spes were stable, convenient, inexpensive and suitable for large-area screen-printing. with these spes, we explored the fabrication of a novel, disposable and highly sensitive electro-analytical immunosensor using graphene nanosheets (gs) and horseradish peroxidase (hrp)-labeled signal antibody functionalized with gold nanoparticles (hrp-ab(2)/au nps). gs was used to increase the conductivity and ...201222770827
chemiluminescence flow biosensor for glucose using mg-al carbonate layered double hydroxides as catalysts and buffer solutions.in this work, serving as supports in immobilizing luminol reagent, catalysts of luminol chemiluminescence (cl), and buffer solutions for the cl reaction, mg-al-co(3) layered double hydroxides (ldhs) were found to trigger luminol cl in weak acid solutions (ph 5.8). the silica sol-gel with glucose oxidase and horseradish peroxidase was immobilized in the first half of the inside surface of a clear quartz tube, and luminol-hybrid mg-al-co(3) ldhs were packed in the second half. therefore, a novel c ...201322770831
a novel membrane-based process to isolate peroxidase from horseradish roots: optimization of operating parameters.the optimization of operating parameters for the isolation of peroxidase from horseradish (armoracia rusticana) roots with ultrafiltration (uf) technology was systemically studied. the effects of uf operating conditions on the transmission of proteins were quantified using the parameter scanning uf. these conditions included solution ph, ionic strength, stirring speed and permeate flux. under optimized conditions, the purity of horseradish peroxidase (hrp) obtained was greater than 84 % after a ...201322773175
electrochemical immunoassay on expression of integrin β1 on tumor cells and drug-resistant tumor cells.an electrochemical indirect competitive immunoassay protocol as a promising cytosensing strategy was developed to detect integrin β1 expression on human breast cancer mcf-7 cells and adriamycin-resistant human breast cancer mcf-7 (mcf-7/adr) cells and quantify the cell number. integrin α5β1 was adsorbed on the gold-nanoparticle modified glassy carbon electrode to bind integrin β1 monoclonal antibody (anti-cd29 mab). a sandwich structure was then formed using nanocomposites which consisted of hor ...201322776180
investigation of glucosinolate profile and qualitative aspects in sprouts and roots of horseradish (armoracia rusticana) using lc-esi-hybrid linear ion trap with fourier transform ion cyclotron resonance mass spectrometry and infrared multiphoton dissociation.within the family of brassicaceae, an important source of glucosinolates (glss) is represented by horseradish ( armoracia rusticana p. gaertner, b. meyer & scherbius), cultivated for its roots, which are grated fresh or processed into a sauce and used as a condiment. the characteristic pungent flavor of the root depends on the abundance of the bioactive gls molecules. in crude plant extracts (sprouts and roots) of an accession of horseradish largely diffused in the basilicata region (southern it ...201222779710
capillary electrophoresis-based immunoassay for the determination of brevetoxin-b in shellfish using electrochemical detection.neurotoxic shellfish poisoning is a significant food-borne disease caused by potent cyclic polyether toxins (brevetoxins) that accumulate in the flesh of shellfish. here we report a new procedure for brevetoxin analysis by capillary electrophoresis-based immunoassay (ce-ia) with electrochemical (ec) detection. in this method, after the competitive immunoreaction in liquid phase, the horseradish peroxidase (hrp)-labeled antigen and the bound enzyme-labeled complex were separated and then the syst ...201322781183
in vitro human cell-free expression system for synthesis of malaria proteins.in this study, we performed cell-free expression of plasmodium proteins using the in vitro human cell-free protein expression systems for dna and mrna. malaria rhoptry genes (pfc14_0344, pfc0120w, py01759, py00763, py07482, and py04666) and a maurer's cleft gene (pfa0680c) identified from proteome analysis studies were cloned into the pt7cfe1-chis expression vector. following a coupled transcription-translation procedure, expressed proteins were analyzed by his-tag staining and by western blotti ...201222782471
morphology antibody chromosome technique for determining phenotype and genetic status of the same cell.the morphology antibody chromosome (mac) technique is a combination of methods that permits analysis of both phenotypic and genetic evaluation on a single interphase or mitotic cell as a basis for lineage analysis of neoplastic and normal cells. this unit describes mac with sequential phenotypic analysis using antibody and an alkaline phosphatase anti-alkaline phosphatase (apaap) complex and genotypic analysis using in situ hybridization with either enzymatic or fluorescence detection. alternate ...201222786612
a highly efficient nano-cluster artificial peroxidase and its direct electrochemistry on a nano complex modified glassy carbon electrode.a nano-cluster with highly efficient peroxide activity was constructed based on nafion (nf) and cytochrome c (cyt c). uv-vis spectrometry and transmission electron microscopy (tem) methods were utilized for characterization of the nano-structured enzyme or artificial peroxidase (ap). the nano-cluster was composed of a chain-ball structure, with an average ball size of about 40 nm. the michaelis-menten (k(m)) and catalytic rate (k(cat)) constants of the ap were determined to be 2.5 ± 0.4 µm and 0 ...201222790375
nanogold-polyaniline-nanogold microspheres-functionalized molecular tags for sensitive electrochemical immunoassay of thyroid-stimulating hormone.methods based on nanomaterial labels have been developed for electrochemical immunosensors and immunoassays, but most involved low sensitivity. herein a novel class of molecular tags, nanogold-polyaniline-nanogold microspheres (gpgs), was first synthesized and functionalized with horseradish peroxidase-conjugated thyroid-stimulating hormone antibody (hrp-ab(2)) for sensitive electrochemical immunoassay of thyroid-stimulating hormone (tsh). x-ray diffraction, confocal raman spectroscopy, scanning ...201222790703
protection of blood retinal barrier and systemic vasculature by insulin-like growth factor binding protein-3.previously, we showed that insulin growth factor (igf)-1 binding protein-3 (igfbp-3), independent of igf-1, reduces pathological angiogenesis in a mouse model of the oxygen-induced retinopathy (oir). the current study evaluates novel endothelium-dependent functions of igfbp-3 including blood retinal barrier (brb) integrity and vasorelaxation. to evaluate vascular barrier function, either plasmid expressing igfbp-3 under the regulation of an endothelial-specific promoter or a control plasmid was ...201222792172
[a new look at reactions with participation of metal-porphyrines].reactions ofnucleophilic substitution and enzymatic processes with participation of metal-porphyrins (mp) are considered from the point of view of zn-tetraphenylporphin (zn-tphp) coordination with corresponding ligand/nucleophyl/substrate/base. linear correlations perform between kinetic parameters of process of coordination of zn-tphp in chloroform (constants of stability) and reactions of nucleophilic substitution both in aqueous and organic solvents with participation ofpyridines, n-oxides of ...201322792729
amplified electrochemical detection of a cancer biomarker by enhanced precipitation using horseradish peroxidase attached on carbon nanotubes.an electrochemical nanoimmunosensor based on multiwall carbon nanotubes (mwcnts)/gold nanoparticles (aunps) was developed for the amplified detection of prostate specific antigen (psa). the amplified detection was achieved by the enhanced precipitation of 4-chloro-1-naphthol (cn) using a higher number of horseradish peroxidase (hrp) molecules attached on mwcnts. the psa nanoimmunosensor was fabricated by immobilizing a monoclonal anti-psa antibody (anti-psa) on the aunp-attached thiolated mwcnt ...201222793977
enhanced lateral flow immunoassay using gold nanoparticles loaded with enzymes.the use of gold nanoparticles (aunps) as labeling carriers in combination with the enzymatic activity of the horseradish peroxidase (hrp) in order to achieve an improved optical lateral flow immunoassay (lfia) performance is presented here. briefly in a lfia with an immune-sandwich format aunps are functionalized with a detection antibody already modified with hrp, obtaining an 'enhanced' label. two different detection strategies have been tested: the first one following just the red color of th ...201322795532
[effects of electromagnetic pulse exposure on the permeability of inner blood-retinal barrier model in vitro].to establish the inner blood-retinal barrier (brb) model in vitro by co-culturing rf/6a cells and c6 cells and to investigate the effects of emp (200 kv/m, 200 pulses) exposure on the permeability of the inner brb model in vitro.201222804884
electrochemical genosensor for specific detection of the food-borne pathogen, vibrio cholerae.a disposable horseradish peroxidase (hrp)-based electrochemical genosensor was developed for chronoamperometric detection of single-stranded asymmetric lolb gene pcr amplicon (118 bp in length) of the food-borne pathogen, vibrio cholerae. a two-step sandwich-type hybridization strategy using two specific probes was employed for specific detection of the target single-stranded dna (ssdna). the analytical performances of the detection platform have been evaluated using a synthetic ssdna (st3) whic ...201122805952
production and purification of anti-rhombomys opimus immunoglobulins.zoonotic cutaneous leishmaniasis (zcl) is an increasing public health problem in some endemic regions. horseradish peroxidase (hrp) conjugated rabbit anti-rhombomys opimus (r. opimus) ig is needed for immunoblotting and elisa tests used to explore the immune response of the rodents against the sand fly saliva. in this study, the production of hrp conjugated rabbit anti-r. opimus ig was conducted for the first time.201122808420
programmed cell death in plants: protective effect of tetraphenylphosphonium and tetramethylrhodamine cations used as transmembrane quinone carriers.tetraphenylphosphonium (tpp(+)) and tetramethylrhodamine ethyl ester (tmre(+)) cations used as transmembrane carriers of ubiquinone (mitoq) and plastoquinone (skq, skqr) in mitochondria prevented at nanomolar concentrations the chitosan- or h(2)o(2)-induced destruction of the nucleus in epidermal cells of epidermis isolated from pea leaves. the protective effect of the cations was potentiated by palmitate. penetrating anions of tetraphenylboron (tb(-)) and phenyl dicarbaundecaborane also display ...201222809154
signal amplification of microarray-based immunoassay by optimization of nanoliposome formulations.the use of microarray-based immunoassay is often limited by its sensitivity. to increase the sensitivities of such an immunoassay, liposome encapsulation was explored. two different liposome formations and several preparation methods were examined to optimize encapsulation and signal-enhancing efficacy for enzyme-linked immunosorbent assay (elisa) and antibody array. the signal amplification by liposome encapsulation was demonstrated through a detection for foodborne pathogenic listeria. in plat ...201222809874
vanadium bromoperoxidase-coupled fluorescent assay for flow cytometry sorting of glucose oxidase gene libraries in double emulsions.a vanadium bromoperoxidase-coupled fluorescent assay (viper) for ultrahigh-throughput screening of glucose oxidase (gox) gene libraries employing double emulsions and flow cytometry was developed. the assay is based on detection of the product of a gox reaction, hydrogen peroxide, that is first converted to a hypobromide by vanadium bromoperoxidase in the presence of sodium bromide. the hypobromide is afterwards detected in a reaction with a fluorogenic probe, 3-carboxy-7-(4'-aminophenoxy)-couma ...201222811062
development and application of a double-antigen sandwich enzyme-linked immunosorbent assay for detection of antibodies to porcine circovirus 2.a double-antigen sandwich enzyme-linked immunosorbent assay (elisa) is described for detection of porcine circovirus 2 (pcv2) antibodies using the well-characterized recombinant pcv2 capsid protein. in a comparative test of 394 pig sera against an indirect immunofluorescence (iif) test and a commercial elisa kit (also based on the recombinant pcv2 capsid protein), the results showed that the diagnostic sensitivity, specificity, and accuracy of the assay were, respectively, 90.61, 94.02, and 91.6 ...201222815145
control of a tyrosyl radical mediated protein cross-linking reaction by electrostatic interaction.herein, we demonstrate the control of protein heteroconjugation via a tyrosyl coupling reaction by using electrostatic interaction. aspartic acid and arginine were introduced to a tyrosine containing peptide tag (y-tag) to provide electrostatic charge. designed negatively or positively charged y-tags were tethered to the c-terminus of escherichia coli alkaline phosphatase (bap) and streptavidin (sa), and these model proteins were subjected to horseradish peroxidase (hrp) treatment. the negativel ...201222816877
performance of an organic photodiode as an optical detector and its application to fluorometric flow-immunoassay for iga.the performance of an organic thin film photodiode (opd), fabricated from a hetero-junction comprised of two layers of c(60) and a phthalocyanine-cu(ii) complex was evaluated by detecting the chemiluminescence generated from the reaction of luminol with horseradish peroxidase in the presence of h(2)o(2), and the fluorescence from resorufin, as an optical detector. the photocurrent of the opd was linear with respect to the power of light from a commercial led. the sensitivity of the opd was suffi ...201222817940
development of an automatic multi-channel ink-jet ejection chemiluminescence system and its application to the determination of horseradish peroxidase.in this work, an automatic multi-channel ink-jet for chemiluminescence (cl) analysis was developed. the four-channel ink-jet device was controlled by a home-made circuit. differing from the classic flow injection cl, the whole procedure for cl analysis was automatically completed on a hydrophobic glass side. cl reaction of luminal and hydrogen peroxide for the determination of horseradish peroxidase (hrp) was selected as an application to automatic cl analysis platform. all solutions delivered b ...201222819052
vitronectin: possible contribution to the closed-eye external host-defense mechanism.eye closure causes a shift in the preocular tear film, from a reflex tear-rich layer which is in dynamic equilibrium to a secretory iga-rich layer which is stagnant in nature. this is accompanied by complement conversion and plasminogen activation, followed by polymorphonuclear (pmn) cell recruitment. it is suggested that this shift to a secretory iga and pmn cell-rich layer serves to protect the ocular surfaces from trapped microorganisms. the mechanisms whereby autologous damage is avoided are ...199322822923
[the influence of strabismus and monocular deprivation on the size of callosal cells in cortical areas 17 and 18 of the cat].to reveal the changes in visual cortex structure following impaired early binocular experience, the size (somatic area) of callosal cells in areas 17, 18 ofmonocularly deprived and convergent strabismic cats was measured. horseradish peroxidase was injected into the single ocular dominance columns of areas 17, 18 and the transition zone 17/18. in both groups of impaired cats the mean size of callosal cells in area 17 was increased in comparison to intact cats. in area 18, the similar difference ...201222834337
a perioculomotor nitridergic population in the macaque and cat.we determined the distribution of cells containing synthetic enzymes for the unconventional neurotransmitter, nitric oxide, with respect to the known populations within the oculomotor complex.201222836763
synthesis and characterization of a novel boronic acid-functionalized chitosan polymeric nanosphere for highly specific enrichment of glycopeptides.in this study we describe a method for highly specific enrichment of glycopeptides with boronic acid-functionalized chitosan polymeric nanospheres and matrix assisted laser desorption-ionization mass spectrometry (maldi-ms). this is the first time chitosan has been used to create nanosphere support material for selective enrichment of glycopeptides by modification with glycidyl methacrylate (gma) and derivatization with 3-aminophenylboronic acid (apb). due to their multifunctional chemical moiet ...201222840004
sensitive chemiluminescent immunoassay of triclopyr by digital image analysis.an image based detection of chemiluminescence enzyme-linked immunosorbent assay (cl-elisa) for the quantification of triclopyr has been developed. the immunoassay was an indirect competitive immunoassay with an anti-rabbit secondary antibody conjugated to horseradish peroxidase (hrp). chemiluminescence was produced by the luminol/h(2)o(2)/hrp reaction, detected by a monochrome video ccd camera and digitized with an imagraph ic-pci frame grabber using a custom program developed in c(++) (microsof ...201222841045
effect of organic solvents on peroxidases from rice and horseradish: prospects for enzyme based applications.a feasibility test for rice peroxidase (rp) enzyme as a substitute for horseradish peroxidase (hrp) was carried out. the activity of hrp was maximum at 30 °c with ph 6.0-7.0. the purified rice peroxidase showed optimum activity at 30 °c with ph 7-8 and was thermostable till 68 °c, which is higher than the temperature reported for hrp. rp obeyed michaelis-menten kinetics. with increasing substrate concentrations, rp and hrp had v(max) as 8.23 μm min(-1) and 4.21 μm min(-1) and k(m) as 5.585 and 3 ...201222841068
biotin determination in food supplements by an electrochemical magneto biosensor.an electrochemical magneto biosensor for the rapid determination of biotin in food samples is reported. the affinity reaction was performed on streptavidin-modified magnetic microbeads as a solid support in a direct competitive format. the biotinylated horseradish peroxidase enzyme (biotin-hrp) competes with free biotin in the sample for the binding sites of streptavidin on the magnetic microbeads. the modified magnetic beads were then easily captured by a magneto graphite-epoxy composite electr ...201222841112
redox-sensitive sulfenic acid modification regulates surface expression of the cardiovascular voltage-gated potassium channel kv1.5.kv1.5 (kcna5) is expressed in the heart, where it underlies the i(kur) current that controls atrial repolarization, and in the pulmonary vasculature, where it regulates vessel contractility in response to changes in oxygen tension. atrial fibrillation and hypoxic pulmonary hypertension are characterized by downregulation of kv1.5 protein expression, as well as with oxidative stress. formation of sulfenic acid on cysteine residues of proteins is an important, dynamic mechanism for protein regulat ...201222843785
low concentration of silver nanoparticles not only enhances the activity of horseradish peroxidase but alter the structure also.chemical synthesis of ag-nps was carried out using reduction method. the reduction mechanistic approach of silver ions was found to be a basic clue for the formation of the ag-nps. the nanoparticles were characterized by uv-vis, ft-ir and tem analysis. we had designed some experiments in support of our hypothesis, "low concentrations of novel nanoparticles (silver and gold) increases the activity of plant peroxidases and alter their structure also", we had used ag-nps and hrp as models. the immo ...201222848490
inhibition of heme peroxidases by melamine.in 2008 melamine-contaminated infant formula and dairy products in china led to over 50,000 hospitalizations of children due to renal injuries. in north america during 2007 and in asia during 2004, melamine-contaminated pet food products resulted in numerous pet deaths due to renal failure. animal studies have confirmed the potent renal toxicity of melamine combined with cyanuric acid. we showed previously that the solubility of melamine cyanurate is low at physiologic ph and ionic strength, pro ...201222852071
whole-mount fluorescence in situ hybridization and antibody staining of drosophila embryos.whole-mount rna in situ hybridizations with digoxigenin-conjugated probes and alkaline phosphatase biochemistry have been used widely for many years to map expression pattern domains in the drosophila embryo. to capitalize on the number of molecular markers in the central nervous system (cns) and to enable expression analysis at the single-cell level, fluorescence in situ hybridization procedures are becoming standard. this protocol describes methods for the simultaneous detection of rna and pro ...201222854564
development of an antigen-capture enzyme-linked immunosorbent assay for clostridium perfringens beta2-toxin in porcine feces and the neonatal piglet intestine.an enzyme-linked immunosorbent assay (elisa) was developed for detection and quantitation of beta2-toxin in neonatal piglet intestinal contents. polystyrene plates were coated with polyclonal capture antibodies prepared against consensus recombinant beta2-toxin. the elisa was developed using consensus recombinant beta2-toxin, atypical recombinant beta2-toxin, purified consensus native beta2-toxin, and field samples of neonatal porcine intestinal contents. captured antigen was detected using a ho ...201222855377
highly amplified electrochemiluminescence of peroxydisulfate using bienzyme functionalized palladium nanoparticles as labels for ultrasensitive immunoassay.an immunosensor based on the electrochemiluminescence (ecl) of peroxydisulfate was firstly proposed by coupling the cooperation of two enzymes to in situ generate coreactant with palladium nanoparticles (pdnps) as catalyst for the ecl reaction. pdnps were previously synthesized, which successfully attached to functional carbon nanotubes (fcnts), to bind the secondary antibody and bienzyme (horseradish peroxidase and glucose oxidase). then the prepared bioconjugates were introduced to the electro ...201322857905
a neurobehavioral analysis of the prevention of visual impairment in the dba/2j mouse model of glaucoma.timoptic-xe treatment was used to examine the relationship between age-related changes in intraocular pressure (iop), retinal cell loss, visual ability, and neuronal labeling in the superior colliculus in the dba/2j mouse model of pigmentary glaucoma.201222859742
[establishment of ba-elisa method for detecting cea in human sera].to establish a sensitive biotin-avidin enzyme linked immunosorbent assay (ba-elisa) method for detecting carcinoembryonic antigen (cea) in serum.201222863598
controlled immobilisation of active enzymes on the cowpea mosaic virus capsid.immobilisation of horseradish peroxidase (hrp) and glucose oxidase (gox) via covalent attachment of modified enzyme carbohydrate to the exterior of the cowpea mosaic virus (cpmv) capsid gave high retention of enzymatic activity. the number of enzymes bound per virus was determined to be about eleven for hrp and 2-3 for gox. this illustrates that relatively large biomacromolecules can be readily coupled to the virus surface using simple conjugation strategies. virus-biomacromolecule hybrids have ...201222865109
ultrasensitive electrochemical immunosensor for ca 15-3 using thionine-nanoporous gold-graphene as a platform and horseradish peroxidase-encapsulated liposomes as signal amplification.this paper describes a novel electrochemical immunosensor using a nanoporous gold (npg)/graphene (gn) hybrid platform combined with horseradish peroxidase (hrp)-encapsulated liposomes as labels for the sensitive detection of cancer antigen 15-3 (ca 15-3). the electrochemical detection was based on the released hrp from hrp-encapsulated liposomes toward the reduction of h(2)o(2) with the help of the thionine (th) electron mediator. in the presence of ca 15-3, hrp@liposomes and th-npg-gn formed a ...201222866329
studies on the refolding process of recombinant horseradish peroxidase.horseradish peroxidase (hrp) is an important heme-containing glyco-enzyme that has been used in many biotechnological fields. valuable proteins like hrp can be obtained in sufficient amounts using escherichia coli as an expression system. however, frequently, the expression of recombinant enzyme results in inclusion bodies, and the refolding yield is generally low for proteins such as plant peroxidases. in this study, a recombinant hrp was cloned and expressed in the form of inclusion bodies. in ...201322872497
dna-directed immobilization of horseradish peroxidase onto porous sio2 optical transducers.multifunctional porous si nanostructure is designed to optically monitor enzymatic activity of horseradish peroxidase. first, an oxidized psi optical nanostructure, a fabry-pérot thin film, is synthesized and is used as the optical transducer element. immobilization of the enzyme onto the nanostructure is performed through dna-directed immobilization. preliminary studies demonstrate high enzymatic activity levels of the immobilized horseradish peroxidase, while maintaining its specificity. the c ...201222873686
improved performance of antigen-hrp conjugate-based immunoassays after the addition of anti-hrp antibody and application of a liposomal chemiluminescence marker.to overcome the sensitivity limit for small molecules (haptens) in immunoassays based on antigen-horseradish peroxidase (hrp) conjugates as labels, a novel approach was established that afforded very low detection limits. biotinylated anti-hrp antibody was utilized in order to attach, via a streptavidin bridge, liposomaly entrapped hrp. fentanyl, used as a model antigen, could be determined via the generation of a high-intensity and relatively stable chemiluminescence (cl) signal of a hrp-cataly ...201222878629
biotin igm antibodies in human blood: a previously unknown factor eliciting false results in biotinylation-based immunoassays.biotin is an essential vitamin that binds streptavidin or avidin with high affinity and specificity. as biotin is a small molecule that can be linked to proteins without affecting their biological activity, biotinylation is applied widely in biochemical assays. in our laboratory, igm enzyme immuno assays (eias) of µ-capture format have been set up against many viruses, using as antigen biotinylated virus like particles (vlps) detected by horseradish peroxidase-conjugated streptavidin. we recentl ...201222879954
dna methylation analysis triggered by bulge specific immuno-recognition.we report the sequence-selective discrimination of the cytosine methylation status in dna with anti methylcytosine antibody for the first time. this was realized by employing an affinity measurement involving the target methylcytosine in a bulge region and anti methylcytosine antibody, following hybridization with a bulge-inducing dna to ensure that only the target methylcytosine is located in the bulge. the affinity of the antibody for methylcytosine in the bulge was 79% of that in a single str ...201222880797
in vitro analysis of the monolignol coupling mechanism using dehydrogenative polymerization in the presence of peroxidases and controlled feeding ratios of coniferyl and sinapyl alcohol.in this study, dehydrogenative polymers (dhp) were synthesized in vitro through dehydrogenative polymerization using different ratios of coniferyl alcohol (ca) and sinapyl alcohol (sa) (10:0, 8:2, 6:4, 2:8, 0:10), in order to investigate the monolignol coupling mechanism in the presence of horseradish peroxidase (hrp), coprinus cinereus peroxidase (cip) or soybean peroxidase (sbp) with h(2)o(2), respectively. the turnover capacities of hrp, cip and sbp were also measured for coniferyl alcohol (c ...201222884779
rapid and sensitive quantification of vibrio cholerae and vibrio mimicus cells in water samples by use of catalyzed reporter deposition fluorescence in situ hybridization combined with solid-phase cytometry.a new protocol for rapid, specific, and sensitive cell-based quantification of vibrio cholerae/vibrio mimicus in water samples was developed. the protocol is based on catalyzed reporter deposition fluorescence in situ hybridization (card-fish) in combination with solid-phase cytometry. for pure cultures, we were able to quantify down to 6 v. cholerae cells on one membrane with a relative precision of 39% and down to 12 cells with a relative precision of 17% after hybridization with the horseradi ...201222885749
sulfate determines the glucosinolate concentration of horseradish in vitro plants (armoracia rusticana gaertn., mey. & scherb.).horseradish plants (armoracia rusticana) contain high concentrations of glucosinolates. former studies have revealed that armoracia plants cultivated in vitro have markedly lower glucosinolate concentrations than those grown in soils. yet, these studies neglected that the sulfate concentration in the growth medium may have had a strong impact on glucosinolate metabolism. accordingly, in this study horseradish in vitro plants were cultivated with differing sulfate concentrations and the glucosino ...201322886455
enzymatic growth of quantum dots: applications to probe glucose oxidase and horseradish peroxidase and sense glucose.three innovative assays are developed for the detection of enzymatic activities of glucose oxidase (gox) and horseradish peroxidase (hrp) by the generation of cds quantum dots (qds) in situ using non-conventional enzymatic reactions. in the first assay, gox catalyzes the oxidation of 1-thio-β-d-glucose to give 1-thio-β-d-gluconic acid. the latter is spontaneously hydrolyzed to β-d-gluconic acid and h2 s, which in the presence of cadmium nitrate yields fluorescent cds nanoparticles. in the second ...201222887879
a bioelectrochemical method for the quantitative description of the hofmeister effect of ionic liquids in aqueous solution.it is imperative to establish a simple, efficient, and practical method to investigate the hofmeister effect of ionic liquids (ils) on the behavior of proteins (enzymes). in this study, the effects of the cations and anions of different ils in aqueous media on the structural stability of horseradish peroxidase (hrp), a model oxidoreductase, were systematically investigated using electrochemical methods. it is found that without ils no direct electron transfer current signals of hrp appear at bar ...201222897433
gold nanoparticles-based nanoconjugates for enhanced enzyme cascade and glucose sensing.we have coupled gold nanoparticles with horseradish peroxidase (hrp) to assemble catalytic nanoconjugates (hrp-aunps) for glucose detection. we found that a proper mixing ratio of hrp/aunps can significantly improve catalytic activity for the cascade reaction, an effect arising from increased spatial coupling between enzymes. such gold nanoparticle-based nanoconjugates are shown to be promising nanosensors for glucose.201222898737
bsa-templated mno2 nanoparticles as both peroxidase and oxidase mimics.inorganic nanomaterials that mimic enzymes are fascinating as they potentially have improved properties relative to native enzymes, such as greater resistance to extremes of ph and temperature and lower sensitivity to proteases. although many artificial enzymes have been investigated, searching for highly-efficient and stable catalysts is still of great interest. in this paper, we first demonstrated that bovine serum albumin (bsa)-stabilized mno(2) nanoparticles (nps) exhibited highly peroxidase ...201222900262
co-immobilization of lipase, glycerol kinase, glycerol-3-phosphate oxidase and peroxidase onto alkylamine glass beads through glutaraldehyde coupling.a method for co-immobilizing lipase from porcine pancreas, glycerol kinase (gk) from cellulomonas spp., glycerol-3-phosphate oxidase (gpo) from aerococcus viridans and peroxidase from horseradish onto zirconia-coated alkylamine glass beads through glutaraldehyde coupling has been described. the co-immobilized enzymes retained 71.4% of initial specific activity with a conjugation yield of 43.6 mg/g support. the optimum ph and km for triolein increased, while vmax was decreased slightly, but incub ...200222905380
[organization of the projections of the substructures of deep mesencephalic nucleus to the striatum in the dog brain].method of retrograde axonal transport of horseradish peroxidase was used to study the organization of the projections of the individual substructures of the deep mesencephalic nucleus complex to the functionally diverse regions of striatal structures of the dog brain (n=20). it was shown that the projection fibers of the neurons of the nucleus profundus mesencephali were directed to the ventro-lateral segment of the nucleus caudatus and the ventral segment of the putamen. the dorsal segment of t ...201222913133
inhibitory effect of silicon nanowires on the polymerase chain reaction.the effect of nanomaterials on biological reactions has received much attention. we report herein that silicon nanowires (sinws) inhibit the polymerase chain reaction (pcr). the inhibitory effect was found to be concentration-dependent, with a minimum inhibitory concentration of about 0.4 mg ml(-1). dna polymerase, restriction endonucleases, lysozyme and horseradish peroxidase maintained their bioactivities after exposure to sinws. also the interaction of sinws with primers and dntp did not lead ...201222914382
bimetallic aupt nanochains: synthesis and their application in electrochemical immunosensor for the detection of carcinoembryonic antigen.the recent development in the nanotechnology has paved the way for a large number of alloyed nanomaterials and devices of desirable properties which have useful functions for electrochemical sensor and biosensor applications. in this paper, bimetallic aupt nanochains were synthesized through a mild chemical method, with which anti-horseradish peroxidase-conjugated anti-carcinoembryonic antigen (hrp-anti-cea-ncaupt) was developed for electrochemical detection of carcinoembryonic antigen (cea) in ...201322921093
cross-linking of structural proteins in ageing skin: an in situ assay for the detection of amine oxidase activity.with increasing age, dynamic tissues such as lungs, blood vessels and skin lose their ability to both deform and recoil, culminating in tissue stiffening. this loss of tissue elasticity, which profoundly impacts tissue function and thus morbidity, may be due not only to changes in the relative abundance of key extracellular matrix proteins within tissues but also to their accumulation of post-translational modifications. whilst to date attention has focussed primarily on the age-related non-enzy ...201322923173
dnazyme-based rolling-circle amplification dna machine for ultrasensitive analysis of microrna in drosophila larva.we present a highly sensitive colorimetric method for microrna (mirna) detection. this method is based on a rolling-circle amplification (rca) dna machine, which integrates rca, nicking enzyme signal amplification and dnazyme signal amplification. the dna machine is triggered by the hybridization of target mirna with a rational designed padlock dna template and activated by rca. the resulting rca product then autonomously replicates a multiple machinery cutter cycle and generates accumulated amo ...201222928468
endothelial cell senescence is associated with disrupted cell-cell junctions and increased monolayer permeability. 201222929066
use of crude extract of lentil plant (lens culinaris medikus) in peroxidase-based analyses: fast kinetic determination of hydrogen peroxide and sarcosine in urine.peroxidase-catalysed reactions are used in a wide variety of analytical applications, most of them based on the final quantification of hydrogen peroxide. clinical tests for glucose, cholesterol, creatine, creatinine or uric acid in blood or urine and enzyme-linked immunosorbent assays for pesticides, hepatitis or acquired immune deficiency syndrome are good examples of such applications. the most widely used and commercially available peroxidase for biotechnological processes and analytical app ...201222932812
a filtration method for rapid preparation of conjugates for immunoassay.modification of protein and other biopolymers by labeling them with small or macromolecules has become a very powerful research tool in biochemistry, molecular biology, diagnostics, and therapeutics. however, current methodologies available for their preparations are not straightforward and take several hours of incubation time. in this paper, we describe a new filtration-assisted technique for covalent conjugation between the reactive functional groups of two different molecules (small or macro ...201222935228
improved covalent immobilization of horseradish peroxidase on macroporous glycidyl methacrylate-based copolymers.a macroporous copolymer of glycidyl methacrylate and ethylene glycol dimethacrylate, poly(gma-co-egdma), with various surface characteristics and mean pore size diameters ranging from 44 to 200 nm was synthesized, modified with 1,2-diaminoethane, and tested as a carrier for immobilization of horseradish peroxidase (hrp) by two covalent methods, glutaraldehyde and periodate. the highest specific activity of around 35 u g(-1) dry weight of carrier was achieved on poly(gma-co-egdma) copolymers with ...201222941271
screening for oxidative stress elicited by engineered nanomaterials: evaluation of acellular dcfh assay.the dcfh assay is commonly used for measuring free radicals generated by engineered nanomaterials (enm), a well-established mechanism of enm toxicity. concerns exist over susceptibility of the dcfh assay to: assay conditions, adsorption of dcfh onto enm, fluorescence quenching and light scattering. these effects vary in magnitude depending on enm physiochemical properties and concentration. a rigorous evaluation of this method is still lacking. the objective was to evaluate performance of the dc ...201222942866
reactivity of nonsteroidal anti-inflammatory drugs with peroxidase: a classification of nonsteroidal anti-inflammatory drugs.to improve understanding of the essential effect of nonsteroidal anti-inflammatory drugs (nsaids) on prostaglandin h synthase (pghs), the reactivity of nsaids with peroxidases and the tyrosyl radical derived from myoglobin was examined.201222943177
formation and stability of interpenetrating polymer network hydrogels consisting of fibrin and hyaluronic acid for tissue engineering.fibrin gel is widely used as a tissue engineering scaffold. however, it has poor mechanical properties, which often result in rapid contraction and degradation of the scaffold. an interpenetrating polymer network (ipn) hydrogel composed of fibrin and hyaluronic acid-tyramine (ha-tyr) was developed to improve the mechanical properties. the fibrin network was formed by cleaving fibrinogen with thrombin, producing fibrin monomers that rapidly polymerize. the ha network was formed through the coupli ...201322943886
peroxidase immobilized on phospholipid bilayers supported on au (111) by dtt self-assembled monolayers: application to dopamine determination.in this work, horseradish peroxidase (hrp) was immobilized on dimyristoylphosphatidylcholine (dmpc) bilayers supported on au (111) by dithiotreitol (dtt) self-assembled monolayers and used as a nanostructured electrochemical biosensor to dopamine determination. the morphology of the phospholipid bilayers and the immobilization of hrp to these layers were characterized by atomic force microscopy (afm). square-wave voltammetry (swv) experiments were done to investigate the performance of the hrp-m ...201322949216
capacitive immunoaffinity biosensor based on vertically paired ring-electrodes.a capacitive biosensor was developed by using a vertically paired ring-electrode for the non-labeled immunoassay. the vertically paired ring-electrode was prepared by sequential deposition and etching processes. two electrodes were layered on glass substrate by sputtering of gold layers with thicknesses of 50 nm and 100 nm, and a parylene-c film with a thickness of 550 nm was positioned between the electrode layers as a dielectric material by thermal deposition. the top layer was made by spin co ...201322951529
a novel paramagnetic substrate for detecting myeloperoxidase activity in vivo.bis-phenylamides and bis-hydroxyindolamides of diethylenetriaminepentaacetic acid-gadolinium (dtpa(gd)) are paramagnetic reducing substrates of peroxidases that enable molecular imaging of peroxidase activity in vivo. specifically, gadolinium chelates of bis-5-hydroxytryptamide-dtpa (bis-5ht-dtpa(gd)) have been used to image localized inflammation in animal models by detecting neutrophil-derived myeloperoxidase (mpo) activity at the inflammation site. however, in other preclinical disease models ...201622954188
surface immobilization of protein via biosilification catalyzed by silicatein fused to glutathione s-transferase (gst).silicatein from suberites domuncula was known to catalyze silica deposition in vitro under near neutral ph and ambient temperature conditions. in this study, we employed gst-glutathione (gsh) interaction system to increase the production of silicatein and develop an efficient protein immobilization method. recombinant silicatein fused with gst (gst-sil) was produced in e. coli and the gst-sil protein was employed on gsh-coated glass plate. gst-sil bound surface or matrix can catalyze the formati ...201322955837
development of a quantitative diagnostic method of estrogen receptor expression levels by immunohistochemistry using organic fluorescent material-assembled nanoparticles.the detection of estrogen receptors (ers) by immunohistochemistry (ihc) using 3,3'-diaminobenzidine (dab) is slightly weak as a prognostic marker, but it is essential to the application of endocrine therapy, such as antiestrogen tamoxifen-based therapy. ihc using dab is a poor quantitative method because horseradish peroxidase (hrp) activity depends on reaction time, temperature and substrate concentration. however, ihc using fluorescent material provides an effective method to quantitatively us ...201222959769
methamphetamine-induced nitric oxide promotes vesicular transport in blood-brain barrier endothelial cells.methamphetamine's (meth) neurotoxicity is thought to be in part due to its ability to induce blood-brain barrier (bbb) dysfunction. here, we investigated the effect of meth on barrier properties of cultured rat primary brain microvascular endothelial cells (bmvecs). transendothelial flux doubled in response to meth, irrespective of the size of tracer used. at the same time, transendothelial electrical resistance was unchanged as was the ultrastructural appearance of inter-endothelial junctions a ...201322960442
characterization and enzyme-conjugation of a specific anti-l1 nanobody.persistent infection of the human papillomaviruses (hpv) has been shown to result in cervical cancer and intraepithelial neoplasia. early detection and screening programs are essential strategies against cervical cancer. a nanobody is the smallest antigen-binding fragment known and is derived from a camelid heavy-chain antibody. this tiny protein shows high solubility and stability. it can be produced cost-effectively with high yield production. in this study, we enriched a nanobody library agai ...201222963491
qualitative and quantitative evaluation of simon™, a new ce-based automated western blot system as applied to vaccine development.many ce-based technologies such as imaged capillary ief, ce-sds, cze, and mekc are well established for analyzing proteins, viruses, or other biomolecules such as polysaccharides. for example, imaged capillary isoelectric focusing (charge-based protein separation) and ce-sds (size-based protein separation) are standard replacement methods in biopharmaceutical industries for tedious and labor intensive ief and sds-page methods, respectively. another important analytical tool for protein character ...201222965727
development and validation of an enzyme-linked immunosorbent assay for the quantification of cytochrome 3a4 in human liver microsomes.little is known about the influence of hepatic pathologies on cytochrome p450 (cyp) mediated drug metabolism in children. the determination of the abundance of the different isoforms in pediatric microsomes may provide valuable information on the mechanisms of possible changes in activity. until now, western blotting was mostly used for abundance measurements, but this technique only provides semi-quantitative data. therefore, this study aimed to develop and validate an indirect elisa for the qu ...201222967564
endocytic structures and synaptic vesicle recycling at a central synapse in awake rats.the synaptic vesicle (sv) cycle has been studied extensively in cultured cells and slice preparations, but not much is known about the roles and relative contributions of endocytic pathways and mechanisms of sv recycling in vivo, under physiological patterns of activity. we employed horseradish peroxidase (hrp) as an in vivo marker of endocytosis at the calyx of held synapse in the awake rat. ex vivo serial section scanning electron microscopy and 3d reconstructions revealed two categories of la ...201222974146
development and applications of simultaneous immunochemical staining and serial detection of overlapping proteins in blotting procedures.immunoblotting techniques are widely used for specific protein identifications and characterizations. the specific bindings of antibodies to epitopes in a protein sequence permits determination of antigens and gives detailed information about protein compositions and expression levels in complex suspensions. however the techniques are mostly restricted to one specific antibody determination. overlaying proteins are detected using numerous repeated gel runs. for multiple but specific protein dete ...201222974836
putrescine biosensor based on putrescine oxidase from kocuria rosea.the novel putrescine oxidase based amperometric biosensor selectively measures putrescine, which can be considered as an indicator of microbial spoilage. putrescine oxidase (puox, ec 1.4.3.10) was isolated from kocuria rosea (micrococcus rubens) by an improved and simplified purification process. cells were grown on brain heart infusion medium supplemented with putrescine. cell-free extract was prepared in tris buffer (ph 8.0) by bead-beater. a newly elaborated step based on three-phase partitio ...201222975122
a homogeneous immunoassay of thyroxine based on microchip electrophoresis and chemiluminescence detection.a homogeneous chemiluminescent immunoassay of thyroxine (t4) present in serum samples is described. the proposed method deployed the competitive immunoreaction of t4 and horseradish peroxidase (hrp)-labeled t4 (hrp-t4) with anti-t4 mouse monoclonal antibody (ab). hrp-t4 and the hrp-t4-ab complex were separated and quantified by using microchip electrophoresis (mce) with chemiluminescence (cl) detection. the mce separation was accomplished within 60 s. highly sensitive cl detection was achieved b ...201322976092
binding of divalent metal ions to calcium-free peroxidase: thermodynamic and kinetic studies.thermodynamics of binding of divalent metal ions including ca(2+), mg(2+), ba(2+), and cd(2+) to ca-free horseradish peroxidase (hrp) enzyme was investigated using uv/vis spectrophotometry and molecular-mechanic (mm) calculations. according to the obtained binding and thermodynamic parameters, trend of the relative binding affinities of these divalent metal cations was found to be: ca(2+) > cd(2+) > mg(2+) > ba(2+). binding analysis based on scatchard and hill models showed positive cooperativit ...201222976971
highly sensitive and selective chemiluminescent imaging for dna detection by ligation-mediated rolling circle amplified synthesis of dnazyme.a highly sensitive dna biosensing method down to sub-femtomolar level with excellent selectivity was proposed by designing an amplified synthesis of horseradish peroxidase mimicking dnazyme and introducing the amplified dnazyme to chemiluminescent (cl) imaging. the amplified synthesis was achieved by combining a target dna related ligase reaction with rolling circle amplification (rca), which produced thousands of repeated sequences to bind hemin and form a mass of horseradish peroxidase-mimicin ...201322981413
energy filtering transmission electron microscopy immunocytochemistry and antigen retrieval of surface layer proteins from tannerella forsythensis using microwave or autoclave heating with citraconic anhydride.tannerella forsythensis (bacteroides forsythus), an anaerobic gram-negative species of bacteria that plays a role in the progression of periodontal disease, has a unique bacterial protein profile. it is characterized by two unique protein bands with molecular weights of more than 200 kda. it also is known to have a typical surface layer (s-layer) consisting of regularly arrayed subunits outside the outer membrane. we examined the relationship between high molecular weight proteins and the s-laye ...201222984898
superoxide reaction with tyrosyl radicals generates para-hydroperoxy and para-hydroxy derivatives of tyrosine.tyrosine-derived hydroperoxides are formed in peptides and proteins exposed to enzymatic or cellular sources of superoxide and oxidizing species as a result of the nearly diffusion-limited reaction between tyrosyl radical and superoxide. however, the structure of these products, which informs their reactivity in biology, has not been unequivocally established. we report here the complete characterization of the products formed in the addition of superoxide, generated from xanthine oxidase, to se ...201222989205
endocytic tubules regulated by rab gtpases 5 and 11 are used for envelopment of herpes simplex virus.enveloped viruses employ diverse and complex strategies for wrapping at cellular membranes, many of which are poorly understood. here, an ultrastructural study of herpes simplex virus 1 (hsv1)-infected cells revealed envelopment in tubular membranes. these tubules were labelled by the fluid phase marker horseradish peroxidase (hrp), and were observed to wrap capsids as early as 2 min after hrp addition, indicating that the envelope had recently cycled from the cell surface. consistent with this, ...201222990238
the prognostic value of the immunohistochemical aspects of tumor suppressor genes p53, bcl-2, pten and nuclear proliferative antigen ki-67 in resected colorectal carcinoma.this study aim was to identify the relations between tumor suppressor genes (p53, bcl-2, pten), nuclear proliferative antigen ki-67 and epidemiologic, morphologic and histologic patient related factors, in colorectal cancer.201222990545
improved chemiluminescence assay for measuring antioxidant capacity of seminal plasma.an improved enhanced chemiluminescence antioxidant assay utilizes horseradish peroxidase conjugate and luminol to produce a cell-free oxygen radical generating system. we introduce the use of a peroxidase enzyme stabilizer to prolong the production of oxygen radicals at a steady rate. addition of antioxidants temporarily interrupts oxygen radical generation, resulting in an inhibition curve. a linear relationship exists between the area of the inhibition curve and the molar quantity of added ant ...201322992928
role of the ribose-specific marker furfuryl-amine in the formation of aroma active 1-(furan-2-ylmethyl)-1h-pyrrole (or furfuryl-pyrrole) derivatives.furfuryl-pyrroles possess a diverse range of organoleptic properties described as roasted, chocolaty, green, horseradish-like, and mushroom-like and are detected in various foods such as coffee, chocolate, popcorn, and roasted chicken. although their origin in food was attributed to furfuryl-amine, the latter has not been detected so far in maillard model systems or in foods. in this study, furfuryl-amine was shown to be formed specifically from ribose through nitrogen atom transfer from the α-a ...201222994507
in situ svvyglr peptide conjugation into injectable gelatin-poly(ethylene glycol)-tyramine hydrogel via enzyme-mediated reaction for enhancement of endothelial cell activity and neo-vascularization.tissue engineering therapies require biocompatible and bioactive biomaterials that are capable of encouraging an angiogenic response for effective tissue regeneration. in this study, a svvyglr peptide, which functions as a potent angiogenic factor, was conjugated into injectable gelatin-poly(ethylene glycol)-tyramine (gpt) hydrogels in situ to enhance endothelial cell activities and neo-vascularization. svvyglrggy (sv-y) conjugated gpt (sv-gpt) hydrogels were formed in situ via enzyme-mediated r ...201222998168
composite cryogel with immobilized concanavalin a for affinity chromatography of glycoproteins.composite cryogels containing porous adsorbent particles were prepared under cryogelation conditions. the composites with immobilized concanavalin a (con a) were used for capturing glycoproteins. adsorbent particles were introduced into the structure in order to improve the capacity and to facilitate the handling of the particles. the monolithic composite cryogels were produced from suspensions of polyvinyl alcohol particles and porous adsorbent particles and cross-linked under acidic conditions ...201223002026
taml activator-based amperometric analytical devices as alternatives to peroxidase biosensors.the ferric taml catalysts [fe{c(6)h(2)-1,2-( ncocme(2)nco)(2)cme(2)}(oh(2))](-) (1) with counterions na(+) (a) and pph(4)(+) (b) function similar to horseradish peroxidase in the mediated electron transfer relays, which constitute a basis for amperometric biosensors. the mediators are mono- and bis-cyclometalated ru and os compounds of the type of [m(c∼n)(x)(n∼n)(3-x)](m+) with x = 1 and 2 (n∼n = 2,2'-bipyridine, (-)c∼n = 2-phenylpyridinato). cyclic voltammograms of the ru and os compounds are n ...201223005918
a sensitive method for rapid detection of alkyl halides and dehalogenase activity using a multistep enzyme assay.a method for the detection of haloalkane conversion to the corresponding alcohols by haloalkane dehalogenases is described. it is based on a multistage enzyme reaction which allows for the analysis of alkyl halides in buffered systems. irreversible hydrolytic dehalogenation catalyzed by haloalkane dehalogenase dhaa from rhodococcus erythropolis transfers an alkyl halide into a corresponding alcohol that is further oxidized by alcohol oxidase aox from pichia pastoris yielding a respective aldehyd ...201223006907
filtration, adsorption and immunodetection of virus using polyelectrolyte multilayer-modified paper.a new method for detection of viruses has been developed. the entire assay can be performed within 2h, and consists of a polyelectrolyte-multilayer-modified cellulosic filter paper combined with immunodetection. the m13 bacteriophage was used as a model virus. a visual colour-based detection system, anti-m13 horseradish peroxidase (hrp) conjugate and 3,3',5,5'-tetramethylbenzidine (tmb), was selected to allow semi-quantitative assessment by human eye, or quantitative assessment using a digital s ...201323010020
a novel immunosensor for detecting toxoplasma gondii-specific igm based on goldmag nanoparticles and graphene sheets.a novel electrochemical immunosensor for detecting toxoplasma gondii-specific igm (tg-igm) was constructed based on goldmag (au-fe(3)o(4)) nanoparticles and graphene sheets (gs). thionine (thi), as a mediator, was first electropolymerized on a nafion-gs (nf-gs) modified electrode. subsequently, gold nanoparticles (aunps) were attached onto the poly-thionine film through π-stacking interactions, and then were used to immobilize toxoplasma gondii antigen (tg-ag) for immunosensor fabrication. a san ...201323010058
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