[Determination of S-phenylmercapturic acid in urine by on-line enrichment liquid chromatography tandem mass spectrometry].

OBJECTIVE

To develop on-line enrichment liquid chromatography tandem mass (LC-MS/MS) method for determination of S-phenylmercapturic acid (S-PMA) in urine.

METHODS

With d2-S-PMA added as internal standard, the urine samples were cleaned up and concentrated on Hypersil GOLD (20 mm x 2.1 mm x 12.0 microm) columns, and the targeted compounds were analyzed by HPLC-MS/MS under negative ion mode using Hypersil GOLD (50 mm x 2.1 mm x 3.0 microm) columns as analyzed columns. In the process of enrichment, the mobile phase is CH3OH: HCOOH (0.2%) = 5:95 (volume ratio), the flow rate is 1.50 ml/min. During the analysis, the mobile phase is CH3CN and HCOOH (0.2%) gradient elution, the flow rate is 350 microl/min.

RESULTS

The linear range was 0-500 ng/ml. The related coefficient was 0.9986. The detection limit was 8.0 ng/ml. The recoveries were 78.2%-84.5%. The relative standard deviation was 1.49% (n = 5).

CONCLUSION

The method uses internal standard method, it was used for determination of S-phenylmercapturic acid in the urine, sample don't need too much pretreatment, the sample volume to reduce, the organic solvent volume decrease. The method was simple, rapid, sensitive and accurate. It was for the detecting for S-phenylmercapturic acid in urine.