“…Moreover, 500-fold Na + , K + , NO 3 − , 150-fold lactose, 100-fold urea, sucrose, Mg 2+ , SO 4 2− , Ca 2+ , 50-fold glucose, fructose, 5-fold ascorbic acid, histidine, aspartic acid, glycine, serine, 2-fold dopamine, threonine, valine, phenylalanine did not affect the determination of trp (<5 % of response current change). These results indicated good selectivity of the proposed electrode.…”