✍ Scribed by Carl A. Groom; John H.T. Luong; Rama Thatipalmala
No coin nor oath required. For personal study only.
diator relative to oxygen often removes the need for con-4-Aminodiphenylamine (N-phenyl-1,4-phenylenedi-stant sample mixing. Incorporation of mediators such as amine, CAS 101-54-2) and its water-soluble HCl salt (CAS 1,1-dimethylferrocene or tetrathiafulvalene together with 2198-59-6) were demonstrated to be efficient mediators an oxidase enables the biosensor to function at a low apfor glucose oxidase, lactate oxidase, xanthine oxidase, plied potential (100 mV or less, platinum vs Ag/AgCl). This and lysine oxidase. Using cyclic voltammetry, single oxicondition eliminates the electroactive interferences due to dative peak potentials were observed for scans ranging uric acid and acetaminophen which are normally encounfrom 0 to 0.5 V vs Ag/AgCl. The half-wave potential for tered in the assay of biological samples (1,2). The concept both preparations was 0.11 V vs Ag/AgCl at pH 7 and of using an immobilized layer of glucose oxidase together decreased 59 mV per unit pH increase. Peak current with a ferrocene derivative has formed the basis of the data were analyzed to estimate diffusivities of 0.8 1 10 05 commercial ExacTech glucose meter produced by Medicm 2 /s for soluble 4-ADPA HCl, and 2.36 1 10 05 cm 2 /s for sense (Cambridge, MA) (2). Interferences due to ascorbic 4-ADPA solubilized in 2.5 mM 2-hydroxypropyl-b-cycloacid are not completely eliminated at 0-100 mV vs Ag/ dextrin. The overall second-order kinetic constants (k) AgCl, but can be reduced to nonsignificant levels. A numfor the reaction of reduced glucose oxidase with oxiber of commercially available biosensor systems use celludized 4-ADPA HCl and 4-ADPA in cyclodextrin were estilose acetate permselective membranes to exclude all commated to be 1.8 1 10 5 and 1.7 1 10 5 M 01 s 01 , respectively, pounds of molecular weight greater than 100-200 Da such using cyclic voltammetry measurements at varied scan as ascorbic acid, glutathione, and uric acid, but the added rates and enzyme concentrations. Both preparations diffusional barrier adversely affects the detection limit, proved to be suitable electron acceptors for horseradish linear range, and response time (3). To date, permselective peroxidase, as indicated by changes in absorbance specmembranes have not successfully been applied to the detra upon oxidation or reduction. The electrochemical and spectral behavior of the preparations were applied velopment of disposable sensors. A negatively charged diin conjunction with glucose oxidase to devise mediated alysis membrane can also be used to circumvent the aforeamperometric and hydrogen peroxide-coupled spectromentioned electroactive species. Such a membrane, photometric assays for glucose. The results of both however, only rejects up to 0.082 mM of ascorbic acid and assays compared favorably with the hexokinase refer-0.464 mM of uric acid. Higher concentrations of these subence method.
📜 SIMILAR VOLUMES