title: FET-microbial sensor for xylose detection based on Gluconobacter oxydans cells.
abstract: A potentiometric biosensor for xylose was devised utilizing Gluconobacter oxydans whole cells. Immobilization methods based on physical adsorption were used for G. oxydans cells and extracellular pH changes resulting from xylose dehydrogenation were monitored by a field effect transistor (FET). The G. oxydans, FET-based sensor detected xylose at a lower limit of 0.5 mM. From 5.0 to 30 mM xylose, the response of the sensor was linear. Expectedly, output signals were significantly suppressed by buffer (Tris-HCl). Responses were essentially stable for at least four weeks of storage and showed only a slight loss of initial xylose sensitivity. Xylitol exerted an insignificant influence on the sensor's response to xylose. However, the response to glucose was 5 times higher in relation to that of xylose at the same concentration (1 mM). For xylose determinations in the presence of glucose, a two-step assay is discussed.
authors: Institute of Biochemistry and Physiology of Microorganisms, Russian Academy of Sciences, Puschino, Moscow Region, Russia.
authors: A N
authors: AN
authors: Reshetilov
authors: M V
authors: MV
authors: Donova
authors: D V
authors: DV
authors: Dovbnya
authors: A M
authors: AM
authors: Boronin
authors: T D
authors: TD
authors: Leathers
authors: R V
authors: RV
authors: Greene
mesh_terms: D016947:Acetobacteraceae / Q000166:cytology*; D015374:Biosensing Techniques; D002021:Buffers; D002138:Calibration; D006863:Hydrogen-Ion Concentration; D011199:Potentiometry; D013379:Substrate Specificity; D014173:Transistors, Electronic; D014993:Xylitol; D014994:Xylose / Q000032:analysis*
chemical_list: D002021:Buffers; D014994:Xylose; D014993:Xylitol