Chemiluminescence Determination of L-Tryptophan in Compound Amino Acid Injection Based on Capillary Electrophoresis AnalysisAuthor(s): Yunfang Wu and Suqin Han
A rapid and sensitive capillary electrophoresis chemiluminescence (CE-CL) method for the determination of L-tryptophan (L-Trp) in compound amino acid injection was developed. The method is based on the inhibitory effect of L-Trp on the CL signal of diperiodatoargentate (III)-luminol CL system in alkaline solution. Under optimized conditions, the relative CL intensity was linear with the L-Trp concentration in the range of 2.0×10–8 to1.0×10–6 M with a limit of detection of 9.0×10–9 M. The relative standard deviation at 7.0×10–8 M L-Trp (n =5) was 3.1%. A possible mechanism was investigated.