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A ratiometric fluorescent probe for hypoxanthine detection in aquatic products based on the enzyme mimics and fluorescence of cobalt-doped carbon nitride
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作者 Xin Wang Chengyi Hong +1 位作者 Zhengzhong Lin Zhiyong Huang 《Food Science and Human Wellness》 SCIE CSCD 2024年第2期879-884,共6页
A ratiometric fluorescent probe for hypoxanthine(Hx)detection was established based on the mimic enzyme and fluorescence characteristics of cobalt-doped graphite-phase carbon nitride(Co doped g-C_(3)N_(4)).In addition... A ratiometric fluorescent probe for hypoxanthine(Hx)detection was established based on the mimic enzyme and fluorescence characteristics of cobalt-doped graphite-phase carbon nitride(Co doped g-C_(3)N_(4)).In addition to emitting strong fluorescence,the peroxidase activity of Co doped g-C_(3)N_(4)can catalyze the reaction of O-phenylenediamine and H_(2)O_(2)to produce diallyl phthalate which can emit yellow fluorescence at 570 nm.Through the decomposition of Hx by xanthine oxidase,Hx can be indirectly detected by the generating hydrogen peroxide based on the measurement of fluorescent ratio I(F_(570)/F_(370)).The linear range was 1.7-272.2 mg/kg(R^(2)=0.997),and the detection limit was 1.52 mg/kg(3σ/K,n=9).The established method was applied to Hx detection in bass,grass carp,and shrimp,and the data were verified by HPLC.The result shows that the established probe is sensitive,accurate,and reliable,and can be used for Hx detection in aquatic products. 展开更多
关键词 Co doped g-C_(3)N_(4) Ratiometric fluorescent probe hypoxanthine FRESHNESS Aquatic products
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Electrocatalytic Oxidation and Simultaneous Determination of Uric Acid,Xanthine,Hypoxanthine and Dopamine Based on β-Cyclodextrin Modified Glassy Carbon Electrode 被引量:2
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作者 GONG Wei DOU Zhi-yu CUI Li-li LIU Da-jun HE Xing-quan 《Chemical Research in Chinese Universities》 SCIE CAS CSCD 2012年第6期1047-1053,共7页
A novel covalently modified glassy carbon electrode with β-cyclodextrin was prepared via electropolymerization technique for the simultaneous determination of uric acid(UA),xanthine(XA),hypoxanthine(HX) and dop... A novel covalently modified glassy carbon electrode with β-cyclodextrin was prepared via electropolymerization technique for the simultaneous determination of uric acid(UA),xanthine(XA),hypoxanthine(HX) and dopamine(DA).This new electrode presented an excellent electrocatalytic activity towards the oxidation of UA,XA,HX and DA by cyclic voltammetry(CV) method.The oxidation peaks of the four compounds were well defined and had the enhanced peak currents.The separation potentials of the oxidation peaks for DA-UA,UA-XA and XA-HX were 150,390 and 360 mV in CV,respectively.By means of differential pulse voltammetry(DPV) method,the calibration curves in the ranges of 10―225,5―105,10―170 and 5―150 μmol/L were obtained for UA,XA,HX and DA,respectively.The lowest detection limits(S/N=3) were 5,1.25,5 and 1.5 μmol/L for UA,XA,HX and DA,respectively.The practical application of the modified electrode was demonstrated by the determination of DA in hydrochloride injection and UA,XA,HX in human urine samples. 展开更多
关键词 Β-CYCLODEXTRIN Uric acid XANTHINE hypoxanthine DOPAMINE
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Electrochimical determination of uric acid, xanthine and hypoxanthine by poly(xylitol) modified glassy carbon electrode 被引量:1
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作者 窦志宇 崔丽莉 何兴权 《Journal of Central South University》 SCIE EI CAS 2014年第3期870-876,共7页
The novel covalently modified glassy carbon electrode with poly(xylitol) was prepared using an electropolymerization technique for the simultaneous determination of uric acid(UA), xanthine(XA) and hypoxanthine(HX). Th... The novel covalently modified glassy carbon electrode with poly(xylitol) was prepared using an electropolymerization technique for the simultaneous determination of uric acid(UA), xanthine(XA) and hypoxanthine(HX). This new electrode presents an excellent electrocatalytic activity towards the oxidation of UA, XA and HX by cyclic voltammetry(CV) method. The oxidation peaks of the three compounds were well defined and had enhanced the peak currents. The separation potentials of the oxidation peak potentials for UA-XA and XA-HX were 380 and 370 mV in CV, respectively. Using differential pulse voltammetry(DPV) method, the calibration curves in the ranges of 5-55, 1.3-75.3 and 4-59 μmol/L were obtained for HX, XA and UA, respectively. The lowest detection limits(S/N=3) were 4.5, 0.75 and 3.75 μmol/L for HX, XA and UA, respectively. The practical application of the modified electrode was demonstrated by the determination of UA, XA, HX in human urine samples. 展开更多
关键词 XYLITOL ELECTROPOLYMERIZATION uric acid XANTHINE hypoxanthine
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A Novel Flow Injection Optical Fiber Biosensor for Hypoxanthine Based on Luminol Electrochemiluminescence 被引量:1
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作者 LI Ying xiu ZHU Lian de ZHU Guo yi 《Chemical Research in Chinese Universities》 SCIE CAS CSCD 2003年第2期240-244,共5页
关键词 ELECTROCHEMILUMINESCENCE Flow injection Optical fiber biosensor Sol-gel Ceramic-carbon composite electrode hypoxanthine Fish freshness
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Voltammetric Detection of Nanomolar Levels of Hypoxanthine in the Presence of Copper(Ⅱ) at Glassy Carbon Electrode
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作者 Hu Shengshui Cui Dafu Marco Mascini 《Wuhan University Journal of Natural Sciences》 CAS 1999年第1期101-104,共4页
Nanomolar levels of the hypoxanthine in NaOH electrolyte cantaining copper(Ⅱ) can be determined by anodic stripping voltammetry at a glassy carbon electrode. In the present article hypoxanthine Cu + is shown to be ... Nanomolar levels of the hypoxanthine in NaOH electrolyte cantaining copper(Ⅱ) can be determined by anodic stripping voltammetry at a glassy carbon electrode. In the present article hypoxanthine Cu + is shown to be adsorbed on the electrode surface in the presence of an excess of copper(Ⅱ). After accumulation period, hypoxanthine Cu + was stripped from the electrode surface and the anodic current coming near to the oxidation of Cu(Ⅰ) to Cu(Ⅱ) was measured. A linear calibration curve in the range of 5 nmol/L 1.5 mmol/L hypoxanthine, with a detection limit of 0.5 nmol/L hypoxanthine were obtained. 展开更多
关键词 hypoxanthine COPPER glassy carbon electrode stripping voltammetry
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X-Ray Induced Mutation Frequency at the <i>Hypoxanthine Phosphoribosyltransferase</i>Locus in Clinically Relevant Radioresistant Cells
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作者 Yoshikazu Kuwahara Mehryar Habibi Roudkenar +6 位作者 Yusuke Urushihara Yohei Saito Kazuo Tomita Amaneh Mohammadi Roushandeh Tomoaki Sato Akihiro Kurimasa Manabu Fukumoto 《International Journal of Medical Physics, Clinical Engineering and Radiation Oncology》 2017年第4期377-391,共15页
To elucidate the molecular mechanisms underlying cellular radioresistance, clinically relevant radioresistant cell lines were established via long-term exposure to X-rays with stepwise dose escalation. Established cel... To elucidate the molecular mechanisms underlying cellular radioresistance, clinically relevant radioresistant cell lines were established via long-term exposure to X-rays with stepwise dose escalation. Established cells continue to proliferate despite exposure to 2 Gy X-rays/day for more than 30 days, a standard protocol in cancer radiotherapy. DNA repair fidelity in radioresistant and the parental cells by evaluating the mutation frequency at the hypoxanthine phosphoribosyltransferase (HPRT) locus after exposure to X-rays was determined. Mutation spectrum at the HPRT locus was examined by multiplex polymerase chain reaction. Rejoining kinetics of X-ray-induced DNA double strand breaks (dsbs) was evaluated by the detection of phosphorylated histone H2AX (γH2AX) after X-irradiation. The fold increase in the HPRT mutation frequency due to acute radiation was similar between radioresistant and the parental cell lines. However, fractionated radiation (FR) consisting of 2 Gy X-rays/day increased the mutation frequency at the HPRT locus in parental but not in radioresistant cells. Analysis of the FR-induced mutations at the HPRT locus revealed a high frequency of deletion mutations (>70%) in parental but not in radioresistant cells. As assessed by γH2AX immunostaining, DNA dsbs induced by acute exposure to 10 Gy of X-rays were repaired to the control level within 7 days in radioresistant but not in the parental cells. Moreover, 2 Gy × 5 FR increased the number of γH2AX-positive cells in parental cultures but not in radioresistant cultures. DNA dsbs induced by 2 Gy/day FR are repaired with fidelity in radioresistant but not in parental cells. 展开更多
关键词 Clinically RELEVANT Radioresistant (CRR) Cell hypoxanthine PHOSPHORIBOSYLTRANSFERASE (HPRT) Mutation FREQUENCY Phosphorylated Histone H2AX (γH2AX) X-Rays
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Determination of Hypoxanthine in the Presence of Copper by Adsorptive Stripping Voltammetry
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作者 Percio Augusto Mardini Farias Arnaldo Aguiar Castro 《American Journal of Analytical Chemistry》 2014年第5期291-300,共10页
A stripping method for the determination of hypoxanthine in the presence of copper at the submicromolar concentration levels is described. The method is based on controlled adsorptive accumulation of hypoxanthine-copp... A stripping method for the determination of hypoxanthine in the presence of copper at the submicromolar concentration levels is described. The method is based on controlled adsorptive accumulation of hypoxanthine-copper at the thin-film mercury electrode followed by a fast linear scan voltammetric measurement of the surface species. Optimum experimental conditions were found to be the use of 1.0 × 10﹣3 mol·L﹣1 NaOH solution as electrolyte supporting, an accumulation potential of ﹣0.50 V and a linear scan rate of 200 mV·s﹣1. The response of hypoxanthine-copper is linear over the concentration ranges of 10 - 60 ppb. For an accumulation time of 30 minutes, the detection limit was found to be 250 ppt (1.8 × 10﹣9 mol·L﹣1). Adequate conditions for measuring the hypoxanthine in the presence of metal ions, xanthine, uric acid and other nitrogenated bases were also investigated. The utility of the method is demonstrated by the presence of hypoxanthine associated in ATP or ssDNA. 展开更多
关键词 hypoxanthine DETERMINATION XANTHINE Uric Acid COPPER Ion ATP SSDNA Thin-Film Mercury Electrode Fast Linear Scan Stripping VOLTAMMETRY
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On-line electrochemical measurements of cerebral hypoxanthine of freely moving rats 被引量:1
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作者 ZHANG ZiPin LIN YuQing MAO LanQun 《Science China Chemistry》 SCIE EI CAS 2009年第10期1677-1682,共6页
This study demonstrates an on-line method for continuous measurements of cerebral hypoxanthine in the freely moving rats with integration of selective electrochemical biosensing with in vivo microdialysis sampling. Th... This study demonstrates an on-line method for continuous measurements of cerebral hypoxanthine in the freely moving rats with integration of selective electrochemical biosensing with in vivo microdialysis sampling. The selective electrochemical biosensing is achieved by using xanthine oxidase (XOD) as the specific sensing element and Prussian blue (PB) as the electrocatalyst for the reduction of H2O2 generated from the oxidase-catalyzed reaction. The method is virtually interference-free from the co-existing electroactive species in the brain and exhibits a good stability and reproducibility. Upon integrated with in vivo microdialysis, the on-line method is well suitable for continuous measurements of cerebral hypoxanthine of freely moving rats, which is illustrated by the measurements of the microdi-alysates after the hypoxanthine standard was externally infused into the rat brain. This study essentially offers a facile on-line electrochemical approach to continuous measurements of cerebral hypoxanthine and could find some interesting applications in physiological and pathological investigations associated with hypoxanthine. 展开更多
关键词 ON-LINE method ELECTROCHEMICAL BIOSENSOR hypoxanthine rat BRAIN
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Fluorescent Copper Nanoclusters for Highly Sensitive Monitoring of Hypoxanthine in Fish 被引量:1
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作者 Zi-Xuan Zhao Ya-Ping Guo +2 位作者 Jie Wei Quan-Sheng Chen Xiao-Mei Chen 《Journal of Analysis and Testing》 EI 2021年第1期76-83,共8页
Hypoxanthine(Hx)is an important freshness indicator reflecting the initial freshness of aquatic products.In this work,a novel fluorescence method was established based on cysteine functionalized copper nanoclusters(Cy... Hypoxanthine(Hx)is an important freshness indicator reflecting the initial freshness of aquatic products.In this work,a novel fluorescence method was established based on cysteine functionalized copper nanoclusters(Cys-CuNCs)for monitoring Hx in fish.The as-synthesized Cys-CuNCs exhibit favorable fluorescent property.Importantly,the fluorescence can be quenched significantly when the solution contained a small amount of hydrogen peroxide(H_(2)O_(2)),which was due to both the oxidation of H_(2)O_(2) towards Cys-CuNCs and the resulting Cu(II).Owing to that Hx can generate H_(2)O_(2) under dissolved oxygen and xanthine oxidase(XOD),a fluorescent method for Hx was established.Under the optimal conditions,the Hx concentration in the range of 8–400μmol/L has a good linear relationship with the fluorescence quenching e fficiency,and the detection limit is 0.7μmol/L.Finally,the as-established sensor was applied to determine Hx content in carp.By comparing to the total volatile basic nitrogen(TVB-N)results,the proposed method was feasible in the evaluation of carp freshness. 展开更多
关键词 Copper nanoclusters hypoxanthine FRESHNESS Fluorescence FISH
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Utility of cardiac biomarkers in sports medicine:Focusing on troponin,natriuretic peptides,and hypoxanthine 被引量:1
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作者 Anirban Mahanty Lei Xi 《Sports Medicine and Health Science》 2020年第2期65-71,共7页
Evidence-based consensus suggests that physical activity and regular exercise training can reduce modifiable risk factors as well as rate of mortality and morbidity in patients with chronic diseases,such as cardiovasc... Evidence-based consensus suggests that physical activity and regular exercise training can reduce modifiable risk factors as well as rate of mortality and morbidity in patients with chronic diseases,such as cardiovascular disease(CVD),diabetes,obesity and cancer.Conversely,long-term exercise training and drastic increase in vigorous physical activity may also cause acute cardiovascular events(e.g.acute myocardial infarction)and deleterious cardiac remodeling,particularly when exercise is performed by unfit or susceptible individuals.There is a reversed J-shaped hormesis-like curve between the duration and intensity of exercise and level of CVD risks.Therefore,it is important for an early detection of cardiac injuries in professional and amateur athletes.Under this context,this article focuses on the use of biomarker testing,an indispensable component in the current clinical practices especially in Cardiology and Oncology.We attempt to justify the importance of using circulating biomarkers in routine practices of Sports Medicine for an objective assessment of CVD events following exercise.Special attentions are dedicated to three established or emerging cardiac biomarkers(i.e.cardiac troponins,natriuretic peptides,hypoxanthine)for myocardial tissue hypoxia/ischemia events,muscle stress,and the consequent cellular necrotic injury.Based on these focused analyses,we propose use of circulating biomarker testing in both laboratory and point-of-care settings with an increasingly broader involvement or participation of team physicians,trainers,coaches,primary care doctors,as well as educated athlete community.This diagnostic approach may improve the quality of medical surveillance and preventive measures on exercise-related CVD risks/outcomes. 展开更多
关键词 BIOMARKER Cardiac troponin EXERCISE hypoxanthine Natriuretic peptide Overtraining syndrome Tissue ischemia Risk factors
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Determination of gouty arthritis' biomarkers in human urine using reversed-phase high-performance liquid chromatography 被引量:4
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作者 Lei-Wen Xiang Jing Li +1 位作者 Jin-Ming Lin Hai-Fang Li 《Journal of Pharmaceutical Analysis》 SCIE CAS 2014年第2期153-158,共6页
Creatinine, uric acid, hypoxanthine and xanthine are important diagnostic biomarkers in human urine for gouty arthritis or renal disease diacrisis. A simple method for simultaneous determination of these biomarkers in... Creatinine, uric acid, hypoxanthine and xanthine are important diagnostic biomarkers in human urine for gouty arthritis or renal disease diacrisis. A simple method for simultaneous determination of these biomarkers in urine based on reversed-phase high-performance liquid chromatography (RP-HPLC) with ultraviolet (UV) detector was proposed. After pretreatment by dilution, centrifugation and filtration, the biomarkers in urine samples were separated by ODS-BP column by elution with methanol/50 mM NaH2PO4 buffer solution at pH 5.26 (5:95). Good linearity between peak areas and concentrations of standards was obtained for the biomarkers with correlation coefficients in the range of 0.9957-0.9993. The proposed analytical method has satisfactory repeatability (the recovery of data in a range of creatinine, uric acid, hypoxanthine and xanthine was 93.49-97.90%, 95.38-96.45%, 112.46-115.78%and 90.82-97.13%with standard deviation of o5%, respectively) and the limits of detection (LODs, S/N Z 3) for creatinine, uric acid, hypoxanthine, and xanthine were 0.010, 0.025, 0.050 and 0.025 mg/L, respectively. The established method was proved to be simple, accurate, sensitive and reliable for the quantitation of gouty arthritis' biomarkers in human urine samples. The ratio of creatinine to uric acid was found to be a possible factor for assessment of gouty arthritis. 展开更多
关键词 Gouty arthritis CREATININE Uric acid hypoxanthine XANTHINE High-performance liquid chromatography
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Deposition Pattern of Inosine Monophosphate( IMP) in Pig Muscle during Cold Storage
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作者 Zhu Rongsheng Wang Huaizhong +2 位作者 Lin Song Wang Yanping Hu Hongmei 《Animal Husbandry and Feed Science》 CAS 2017年第4期197-199,218,共4页
[ Objective] The paper was to investigate the degradation and deposition changes of inosine monophosphate (IMP) and its metabolites in muscle of lean pigs and crossbreeding pigs under cold storage condition at 4℃. ... [ Objective] The paper was to investigate the degradation and deposition changes of inosine monophosphate (IMP) and its metabolites in muscle of lean pigs and crossbreeding pigs under cold storage condition at 4℃. [ Method] The contents of IMP and its metabolites in longissimus dorsi of lean pigs and crossbreeding pigs were determined by HPLC method. [ Result] Duroc, Landrace, Yorkshire and DLY pigs shared the same degradation and deposition pattern on IMP, inosine and hypoxanthine. On the second day of cold storage, the content of IMP reached the maximum value, which increased by 0.4% - 15.32% compared with the first day, and then it started to decline. On the fourth day of cold storage, the content of IMP significantly reduced by 23.81% - 39.06% than that on the second day. On the fifth and sixth day of cold storage, the content of IMP kept on falling down slowly and maintained around 1.0 mg/g. While the contents of inosine and hypoxanthine showed an increasing tendency with the extension of cold storage time. [ Conclusion ] Lean pigs Duroc, Landraee and Yorkshire and DLY three- way crossbreeding pigs shared the same degradation and deposition pattern on IMP and its metabolites. With the extension of cold storage, the content of IMP first increased then gradually decreased; while inosine and hypoxanthine gradually increased, and the difference among breeds was not significant. 展开更多
关键词 Pig muscle IMP Inosine hypoxanthine Deposition pattern
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Chemical Quality Indexes of Mullet (<i>Mugil platanus</i>) Stored on Ice
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作者 Sabrina da Costa Silva Andrade Eliane Teixeira Mársico +4 位作者 Ronoel Luiz de Oliveira Godoy Sidney Pacheco Robson Maia Franco Sérgio Borges Mano Carlos Adam Conte-Junior 《Food and Nutrition Sciences》 2014年第11期1030-1039,共10页
The present study was conducted aiming at establishing chemical quality parameters to assess ice stored mullet (0℃ ± 1℃) through the evaluation of nucleotide (adenosine monophosphate [AMP], inosine [HxR] and hy... The present study was conducted aiming at establishing chemical quality parameters to assess ice stored mullet (0℃ ± 1℃) through the evaluation of nucleotide (adenosine monophosphate [AMP], inosine [HxR] and hypoxanthine [Hx]) degradation, biogenic amine (histamine [HI], putrescine [PU], cadaverine [CA] and tyramine [TI]) quantification and mesophilic and psychrotrophic bacteria count monitoring. The microbial load of 7 log CFU·g–1 established as maximum acceptable limit was attained after the 20th day of ice storage. IMP concentration declined during the storage period to levels below the detection limit. HxR content increased only up to time T3 and then declined. Hx level increased during all the storage period. CA and HI content increase was not observed, on the other hand, PU and TI contents significantly increased (p < 0.05) at time T5. We concluded that IMP and Hx concentrations can be adequate parameters to assess mullet quality under the study conditions. HxR proved to be adequate to evaluate the freshness of mullet in the first days of storage while the amines, PU and TI, can be used to assess loss of quality. Mullet obtained in conditions similar to those of the present study and maintained at 0℃ ± 1℃ can be consumed up to the 20th storage day. 展开更多
关键词 Quality Parameters Biogenic Amines Nucleotides hypoxanthine MUGILIDAE
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Disposable amperometric biosensors based on xanthine oxidase immobilized in the Prussian blue modified screen-printed three-electrode system 被引量:1
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作者 TENG YuanJie,CHEN Chen,ZHOU ChangXiang,ZHAO HongLi & LAN MinBo Shanghai key Laboratory of Functional Materials Chemistry Research Center of Analysis Test,East China University of Science and Technology,Shanghai 200237,China 《Science China Chemistry》 SCIE EI CAS 2010年第12期2581-2586,共6页
The screen-printed three-electrode system was applied to fabricate a new type of disposable amperometric xanthine oxidase biosensor.Carbon-working,carbon-counter and Ag/AgCl reference electrodes were all manually prin... The screen-printed three-electrode system was applied to fabricate a new type of disposable amperometric xanthine oxidase biosensor.Carbon-working,carbon-counter and Ag/AgCl reference electrodes were all manually printed on the polyethylene terephthalate substrate forming the screen-printed three-electrode system by the conventional screen-printing process.As a mediator,Prussian blue could not only catalyze the electrochemical reduction of hydrogen peroxide produced from the enzyme reaction,but also keep the favorable potential around 0 V.The optimum operational conditions,including pH,potential and temperature,were investigated.The sensitivities of xanthine and hypoxanthine detections were 13.83 mA/M and 25.56 mA/M,respectively.A linear relationship was obtained in the concentration range between 0.10μM and 4.98μM for xanthine and between 0.50μM and 3.98μM for hypoxanthine.The small Michaelis-menten constant value of the xanthine oxidase biosensor was calculated to be 3.90 μM.The results indicate that the fabricated xanthine oxidase biosensor is effective and sensitive for the detection of xanthine and hypoxanthine. 展开更多
关键词 XANTHINE OXIDASE XANTHINE hypoxanthine screen-printed three-electrode SYSTEM Prussian blue
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