Advanced LC-MS/MS Method Developed to Screen Six SARMs in Supplements

Selective Androgen Receptor Modulators (SARMs) are synthetic compounds designed to mimic the effects of testosterone, promoting muscle growth and bone density with fewer androgenic side effects. Despite their unapproved status for human use, SARMs are frequently found as undeclared ingredients in dietary supplements, posing significant health risks to consumers. Regulatory bodies and analytical laboratories face a critical challenge in accurately and reliably detecting these illicit substances; this study addresses the urgent need for a robust and validated analytical method to screen for multiple SARMs in complex supplement matrices.

The developed LC-MS/MS method demonstrated excellent analytical performance for all six SARMs. It achieved high linearity with correlation coefficients (R²) consistently above 0.998 for all compounds across the tested concentration range. The method exhibited impressive sensitivity, with LODs ranging from 0.5 ng/mL for Ostarine to 2.0 ng/mL for YK11, and LOQs from 1.5 ng/mL to 5.0 ng/mL, allowing for the detection of even trace amounts. Intra-day and inter-day precision, expressed as relative standard deviation (RSD), were consistently below 3.5% and 5.0%, respectively, indicating high reproducibility. Accuracy, measured as percent recovery, ranged from 92.3% to 108.7% across all SARMs and matrices, confirming minimal matrix interference. The method successfully identified undeclared SARMs in 3 out of 20 commercially available dietary supplements tested, with concentrations ranging from 15 mg to 75 mg per serving, highlighting a significant public health concern.