PREPARATION OF COATED WIRE ELECTRODE BASED ON POLYPYRROLEILYSINE AND IT'S UTILIZATION AS POTENTIOMETRIC SENSOR FOR LYSINE

• Main Author: Ernayati K. (NIM 20503001), Widya
• Format: Theses
• Language: Indonesia
• Online Access: https://digilib.itb.ac.id/gdl/view/9603
• Institution: Institut Teknologi Bandung

ABSTRACT: <br /> <br /> <br /> Films of polypyrrole/L-Lysine have been deposited on platinum wire electrodes by electrochemical oxidation of pyrrole in water solution containing L-Lysine HCl and C104-. Deposition of the film was carried out 50 cycles by potential scan between 0-1100 mV vs. Ag/AgC1. Optimum composition for electropolymerization of coated wire electrode based on polypyrrole/L -lysine was pyrrolellysine/C104: 0,05/0,05/0,1 M in nature pH. The film polypyrrole/L-lysine was analyzed by FTIR. The spectrum indicated that L-lysine was trapped and immobilized on polypyrrole. The electrode exhibiting Nemstian behavior with slope 56.9 approximately 1.8 mV per decade for 5 electrodes at 10-1-10 3 M of lysine, a linear response to lysine concentration spanning four orders of magnitude (10 1-104 M) and a detection limit of 104 M. After 20 days, the response practically unchanged. Selectivity behavior of electrode was studied in the presence of arginine, histidine, alanin and glycine. The electrode showed good selectivity to lysine over alanin and glycine (K=0.14) but poor selectivity in the presence of arginin and histidin with selectivity coefficient (K) 2.64 and 2.46 respectively. The electrode proposed has a good reproducibility with coeficient of variance (CV) was 3.06%. The electrode was applied for detemination of lysine in multivitamin.