Simultaneous screening of dietary supplements for 25 anti-hyperlipidemic substances using ultra-performance liquid chromatography and liquid chromatography/electrospray ionization tandem mass spectrometry.

Rationale: Recently, illegal dietary supplements containing unauthorized compounds have been seized and internationally publicized with a warning to avoid their consumption. This adulteration can be a serious threat to public health because of insufficient and reliable safety data as well as their undesirable side effects. It is, therefore, essential to rapidly and accurately develop and simultaneously validate analytical methods for these unauthorized anti-hyperlipidemic substances.

Methods: Dietary supplements were screened simultaneously for 25 anti-hyperlipidemic drugs using an ultra-high-performance liquid chromatography (UPLC) system with a photodiode array (PDA) detector and LC/electrospray ionization tandem mass spectrometry (LC/ESI-MS/MS). The method validation, according to ICH guidelines, considered specificity, linearity, limit of detection (LOD), limit of quantification (LOQ), precision, accuracy, matrix effects, and stability for solid and liquid blank samples. The established UPLC-PDA and LC/ESI-MS/MS methods were applied to screen 103 dietary supplements for 25 anti-hyperlipidemic substances.

Results: Using the validated methods, the screened samples were found to contain peaks with similar retention times and PDA spectra. By comparing the calculated precursor-product ion ratios with those of standards, lovastatin and lovastatin acid were detected at concentrations from LOQ to 4.12 mg/g and LOQ to 9.65 mg/g, respectively.

Conclusions: The developed UPLC-PDA and LC/ESI-MS/MS analytical methods were applied to 103 real samples, of which 13 samples were found to contain lovastatin and lovastatin acid. In view of the increasing demand for dietary supplements in the treatment of hyperlipidemic diseases, widespread use of these methods will contribute to consumer health by ensuring the safety of dietary supplements.