A fluorescent glucose biosensor based on immobilized glucose oxidase on bamboo inner shell membrane.

A fluorescent glucose biosensor was constructed by immobilizing glucose oxidase on a bamboo inner shell membrane with glutaraldehyde as a cross-linker. The detection scheme was based on the depletion of dissolved oxygen content upon exposure to glucose solution with a concomitant increase in the fluorescence intensity of an oxygen transducer, tris(4,7-diphenyl-1,10-phenanthroline)ruthenium(Pi) ditetrakis(4-chlorophenyl)borate. The enzyme immobilization, effect of pH, temperature and ionic strength have been studied in detail. The biosensor exhibited repeatable response to a 2.0 mM glucose solution with a relative standard deviation of 3.0% (n = 10). It showed good storage stability and maintained 95% of its initial response after it had been kept at 4 degrees C for 8 months. The biosensor has a linear response range of 0.0-0.6 mM glucose with a detection limit of 58 microM (S/N = 3). Common potential interferants in samples do not pose any significant interference on the response of the glucose biosensor. It was successfully applied to the determination of glucose content in some commercial wines and medical glucose injections.