Simultaneous determination of eight cannabinoids in hemp-based dietary supplements via an optimized SE-HPLC-PDA...

The growing availability of hemp-based dietary supplements requires improvement of analytical methods and sample preparation for quality control of such products. This work presents a simple and efficient workflow involving solvent extraction, high-performance liquid chromatography with photodiode array detector, and chemometric data evaluation for the determination of eight cannabinoids in hemp products. Extraction and separation conditions were systematically varied in order to provide the accuracy and reliability of the results as well as high sensitivity and selectivity of analysis. After extraction with ethanol, determination of eight cannabinoids using HPLC was performed. For each compound, an excellent linearity (R > 0.9990) in the range of 0.625-10.0 µg/100 mg oil matrix was obtained. Additionally, basic validation parameters were determined. Intra- and inter-day accuracy, precision, and matrix effect complied with the ±15% tolerance limit, whereas LOD reached value of 0.21 µg/100 mg. The analysis via LC-MS/MS confirmed peak identification. Application of the developed method for the analysis of 19 dietary supplements revealed variability in cannabinoid profiles and concentrations. The observed trends were underlined using chemometric data analysis. The presented method provides reliable results and could be easily implemented in quality control as an interesting alternative to advanced and expensive MS instrumentation.