A NOVEL GLUTAMINE BIOSENSOR SYSTEM BASED ON A CONDUCTANCE-SURFACE ACOUSTIC-WAVE FREQUENCY-RESPONSE

A new type of glutamine biosensor system based on a conductance-surfac e acoustic wave (SAW) frequency response, in which a SAW resonator osc illating at 61 MHz and a biosensor involving kidney cortex tissue or E scherichia coliform and a pair of parallel electrodes were used, was d eveloped for the determination of glutamine. Glutaminase from porcine kidney or Escherichia coliform was used as a biocatalyst of the hydrol ysis reaction of glutamine. There was an excellent linear relationship between the frequency shift response and the glutamine concentration in the range of 6.8.10(-4) M to 6.8.10(-3) M. The SAW frequency respon ses obtained from the proposed biosensor system were compared with the conductance response. Some other factors such as pH and selectivity a re also discussed.