ABSTRACT
Objective: To establish an accurate method for the determination of nine chemical drugs (phentolamine mesylate, methyltestosterone, stanozolol, danazol, tadalafil, sildenafil citrate, aildenafil, vardenafil, and thioaildenafil) which were illegally added into the antifatigue health foods. Methods: The UPLC-MS/MS method was adopted. The samples were extracted with methanol by ultrasonic processing and separated on a Waters Acquity BEH-C18 (100 mm × 2.1 mm, 1.7 μm) column with 0.1% formic acid methanol (A) and 0.1% formic acid water (B) as the mobile phase by gradient elution (0-5 min, 50% A; 5-7 min, 50%-90% A; 7-9 min, 90%-100% A; 9-10 min, 100%-50% A) at a flow rate of 0.2 mL/min. The injection volume was 5 μL. The column temperature was 40 ℃. The positive-ion (ESI+) source and MRM mode were used to separate and quantitatively determine the chemicals. The obtained molecular ions, fragment ions, and retention time for MRM channels were used to identify the nine kinds of drugs by comparing with those of reference substances. The obtained peak areas were used to determine the accurate content of the nine chemicals in the antifatigue health foods. Results: A good resolution of the nine kinds of chemical drugs, including phentolamine mesylate, methyltestosterone, stanozolol, danazol, tadalafil, sildenafil citrate, aildenafil, vardenafil, and thioaildenafil, was obtained under this UPLC and MS/MS conditions. The limits of detection (LOD) and quantification (LOQ) were in the ranges of 0.1-0.3 ng/g and 0.3-0.9 ng/g. The standard addition recoveries were in the range of 88.4%-116.3%. There were 68 batches of antifatigue health foods, among which 41 batches were added with the chemicals with positive rate of 60.3%. The sildenafil citrate, tadalafil, aildenafil, and hioaildenafil were detected in samples. Conclusion: The method is simple, accurate, and has high sensitivity, which can be used for the qualitative and quantitative determination of illegally added chemical drugs in the antifatigue health foods.