Determination of 26 anti-diabetic compounds in dietary supplements using a validated UPLC method

ABSTRACTThe purpose of this study was to validate a rapid, simple and accurate method using ultra-performance liquid chromatography (UPLC) for the simultaneous determination of 26 anti-diabetic compounds in illegally adulterated dietary supplements. The method was validated for specificity, linearity, limit of detection, limit of quantitation, precision, accuracy, recovery and stability. All compounds were separated with a resolution of over 1.5. The limits of detection and quantitation were 0.10–1.70 and 0.30–5.10 µg g–1 in a solid sample, respectively; the corresponding values were 0.10–1.25 and 0.30–3.75 µg ml–1 in a liquid sample. The correlation coefficient was > 0.99, precisions were 0.11–3.30% (intra-day) and 0.05–6.15% (inter-day), and accuracies were 83–108% (intra-day) and 85–109% (inter-day). The recoveries were measured with six dosage forms, and the results were acceptable as 87–117% with relative standard deviations ≤ 6.44%. The relative standard deviations of stability were ≤ 3.40% and the ...