XÂY DỰNG QUY TRÌNH ĐỊNH LƯỢNG ĐỒNG THỜI MIMOSIN, COIXOL VÀ KALI SORBAT TRONG CAO CHIẾT BÀI THUỐC TỪ DƯỢC LIỆU XẤU HỔ, VÔNG NEM, HẬU PHÁC NAM, CAM THẢO NAM BẰNG SẮC KÝ LỎNG HIỆU NĂNG CAO (HPLC-PDA)

Abstract

Background: Herbal preparation from four herbs Mimosa pudica, Erythrina variegata, Scoparia dulcis, Cinnamomum iners have sedative effects, treat insomnia, help reduce anxiety and depression effectively. The chemical components present in medicinal herbs such as mimosine and coixol are biologically active substances which is chosen as chemical marker for the herbal extract. Potassium sorbate was added to the formula as preservative ingredient. Objectives: This study was conducted to develop a method for simultaneous quantification of mimosine, coixol, potassium sorbate in herbal prepration from four medicinal herbs by high performance liquid chromatography (HPLC). Method: Sample preparation methods and HPLC conditions were screened and selected. The quantitation method was validated on its system suitability, specificity, linearity, precision and accuracy. Results: Hydrochloride acid 0.2 N was selected as extraction solvent, extraction time is 20 minutes, number of extraction is two times. The optimized HPLC condition employed Shimpack GIST C₁₈ (25 cm × 4.6 mm; 5 μm), a detection wavelength of 277 nm, a column temperature of 40 ^oC, a flow rate of 1 ml/min, and an injection volume of 20 μl. The mobile phases included acetonitrile  and 2.0 g/L sodium n-octanesulfonate adjusted to pH 1.8 by phosphoric acid at ratio 8:92. There was good correlation between peak areas and mimosine, coixol, potassium sorbate concentrations (r² = 0.9997, 0.9999, 0.9996). The RSD values of within-day and inter-day precision, the recovery percentages met requirements according to AOAC guideline. Conclusion: The proposed method could be applied for quality control of the herbal preparation.