High-throughput screening and quantification of eight anti-dandruff agents and antibiotics in hair care products by direct analysis in real-time high-resolution mass spectrometry and HPLC.

Unregistered and excessive use of restricted anti-dandruff agents and the illegal addition of prohibited antibiotics in hair care products pose growing concerns, but monitoring is complicated by lack of integrated screening workflows, as well as the presence of surfactant-rich matrices and metal-chelating properties of some anti-dandruff agents like zinc pyrithione (ZnPT) and piroctone olamine (PO). This study presents a high-throughput "profile-and-quantify" strategy combining direct analysis in real-time high-resolution mass spectrometry (DART-HRMS) with high-performance liquid chromatography (HPLC) to monitor eight targets in shampoos and conditioners. After acetonitrile-methanol ultrasonic extraction, samples were screened using DART-HRMS under optimized parameters. Samples containing the target analytes were subsequently quantified using high-performance liquid chromatography with diode array detector (HPLC-DAD). Validation of this dual-platform approach demonstrated limits of detection ranging from 0.1 to 4 μg/g for the target analytes. For quantitative analysis, the HPLC-DAD assay exhibited good linearity (r² ≥ 0.9995). Spiked recoveries ranged from 96.1% to 107.2% with precision (RSD) ≤ 3.22%. This integrated strategy was applied to a longitudinal survey of 150 commercial products collected from 2022 to 2024. Screening revealed a widespread occurrence of ZnPT, salicylic acid, climbazole, and PO, while also identifying illicit additions of antifungal drugs including miconazole, elubiol, ketoconazole, and clotrimazole in cosmetic formulations. Featuring a rapid screening step of under 2 min per sample prior to targeted quantification, this integrated workflow offers a highly efficient, sensitive, and eco-friendly solution for large-scale regulatory monitoring of cosmetic safety and compliance.