Spectrofluorimetric Determination of Trace Amounts of Tyrosine with 1,5-Bis(4,6-dicholro-1,3,5-triazinylamino) naphthalene

1,5-Bis(4,6-dicholro-1,3,5-triazinylamino) naphthalene was synthesized as a completely new fluorescent reagent and with it a novel fluorescent method was developed for the determination of tyrosine. Under pH 12.0, the fluorescent intensity at λex/λem = 400 nm/465 nm was directly proportional to the concentration of tyrosine in the range of 1.1 × 10−7–1.1 × 10−5 M with the detection limit of 6.8 ×10−8 M. The proposed method has been successfully applied to the determination of trace amounts of tyrosine in human serum and urine samples.