Crayfish walking leg neuronal biosensor for the detection of pyrazinamide and selected local anesthetics

Neuronal biosensors based on the use of crayfish Procambarus clarkii walking legs are reported for the first time and possible analytical applications are explored. The neuronal biosensor is shown to respond selectively to the antitubercular drug and potent food marker, pyrazinamide. The sensor is characterized with respect to selectivity, dose-response relationship, reproducibility and operating lifetime. The detection of local anesthetics is accomplished by monitoring the decrease in pyrazinamide-induced nerve firing in the crayfish walking leg. This decrease is a result of the local anesthetic block of the axonal sodium channels in the nerves. Applicability of this novel procedure to analytical measurements is demonstrated by the construction of dose-response curves for several local anesthetics. Problems associated with the current sensor configuration are presented and future research directions that may improve the neuronal-based biosensor are discussed.