Quenching-chemiluminescence determination of trace amounts of l-tyrosine contained in dietary supplement by chemiluminescence reaction of an iron-phthalocyanine complex

摘要

The chemiluminescence (CL) signal immediately appeared when a hydrogen peroxide solution was injected into an iron-phthalocyanine tetrasulfonic acid (Fe-PTS) aqueous solution. Moreover, the CL intensity of Fe-PTS decreased by adding l-tyrosine. Based on these results, the determination of trace amounts of l-tyrosine was developed using the quenching-chemiluminescence. The calibration curve of l-tyrosine was obtained in the concentration range of 2.0 10 -7 M to 2.0 10 -5 M. Moreover, the relative standard deviation (RSD) was 1.63 % (n=5) for 2.0 10 -6 M l-tyrosine, and its detection limits (3δ) were 1.81 10 -7 M. The spike and recovery experiments for l-tyrosine were performed using a soft drink. Furthermore, the determination of l-tyrosine was applied to supplements containing various kinds of amino acids. Each satisfactory relative recovery was obtained at 98 to 102%.