ADVANCED BIOSENSORS FOR AMINO ACID DETECTION

RESEARCH WILL BE DIRECTED TOWARDS CHARACTERIZING AN ADVANCED BIOSENSOR TECHNOLOGY COMPATIBLE FOR THE REAL-TIME INDIRECT OPTICAL DETECTION OF AMINO ACIDS AS TYPIFIED BY L-PHENYLALANINE, L-DOPA, L-TRYPTOPHAN AND RELATED COMPOUNDS. THE TECHNICAL STRATEGY WILL INVOLVE THE INDIRECT OPTICAL DETECTION OF AMINES AND AMINO ACIDS BY MONITORING CHANGES INDUCED IN THE VISIBLE SPECTRA OF IMMOBILIZED CHROMAGENIC ACYCLIC POLYETHER HOST MOLECULES TO WHICH THE AMINE OR AMINO ACID BECOMES ASSOCIATED. WE ANTICIPATE THAT THE AMINE OR AMINO ACID WILL BECOME INCORPORATED INTO THE CHROMAGENIC POLYETHER VIA HYDROGEN BONDING WITH PROXIMATE NITROGEN ATOMS, RESULTING IN AN INDUCED COLOR CHANGE BY THE ATTACHED AZO DYE CHROMAPHORE VIA A WITHDRAWAL OF ELECTRON DENSITY FROM THE NITROGEN ATOM LOCATED IN THE POLYETHER BACKBONE. IT IS PLANNED TO IMMOBILIZE THE CHROMAGENIC POLYETHER WITHIN A CELLULOSE ACETATE MEMBRANE ATTACHED TO THE END OF A FIBER OPTICS SENSOR. HIGH SENSITIVITY FOR THE DETECTION OF OPTICAL CHANGES INDUCED BY THE PRESENCE OF AMINO ACIDS WILL BE ACCOMPLISHED BY THE USE OF SYNCHRONOUS SAMPLE-AND-HOLD DETECTION CIRCUITRY.