Implementation of gas chromatography tandem mass spectrometry for the analysis of six high boiling point polyhydric alcohols in cosmetics and toothpaste based on precolumn derivatization.

Based on precolumn derivatization, an analytical method has been developed for the determination of six high boiling point polyhydric alcohols (HBPAs, b.p. > 300 ℃) in cosmetics and toothpaste, including erythritol, xylitol, Pro-Xylane-S, inositol, mannitol, and sorbitol. The water dispersion and oil in water samples were extracted by distilled water. The water in oil sample was firstly pre-dispersed with acetone, and then extracted by distilled water. The extract was concentrated to dry under nitrogen, and derivatized with acetic anhydride under the dispersion and catalysis of anhydrous pyridine. The derivatives were detected by gas chromatography-tandem mass spectrometry in the selected reaction monitoring mode, and quantified using arabinitol as internal standard. The experimental conditions such as the selection of columns, extraction procedures, and derivative conditions were optimized. This method was properly validated under the optimized conditions, and obtained excellent analytical features. Specifically, the correlation coefficients in the range of 0.02 ∼ 0.5 mg/L all exceed 0.992. The method limits of detection and quantification were 0.25 and 0.8 mg/kg, respectively. The average recoveries in toothpaste, cosmetics with oil in water and water in oil were 81.8 ∼ 107.1 %, with the relative standard deviation were 3.1 ∼ 7.2 %. The established method was successfully applied to commercial samples of different matrices, showing the advantages of simplicity, sensitivity, and good reproducibility, and can be used for the determination of HBPAs in cosmetics and toothpaste. The proposed methodology solves the problem that there is no detection method for HBPAs in cosmetics.

Simultaneous detection of 93 anabolic androgenic steroids in dietary supplements using gas chromatography tandem mass spectrometry.

In recent years, anabolic androgenic steroids (AASs) have been frequently detected as undeclared ingredients in dietary supplements, where the adverse analytical findings (AAFs) were obtained from analysis of athletes' urine samples after ingestion. In our present study, a GC-MS/MS method for simultaneous detection of 93 anabolic steroids was developed. The chromatographic and mass spectrometric conditions were optimized, and selective reaction monitoring (SRM) mode was adopted to obtain the necessary sensitivity. The whole sample analysis process was completed within 23 min, and the limit of detection (LOD) was 0.5-4 ng.g-1 for solid samples and 0.1-0.8 ng.mL-1 for liquid samples. This method was verified according to World Anti-Doping Agency (WADA) regulations. In addition, the method was found to be specific, accurate. The developed method was then applied to a routine analysis of more than 300 liquid and solid dietary supplements, and one testosterone-positive sample was found. Three suspected drugs, (4-hydroxyandrostenedione, DHEA, and 6-Br androstenedione) were found in three dietary supplements obtained from the Internet through the pretreatment method of this study. This study provides a high-throughput method for screening and monitoring the ingredients of supplements and their subsequent harm to public health.