title: Optimization of a solid phase extraction and hydrophilic interaction liquid chromatography-tandem mass spectrometry method for the determination of metformin in dietary supplements and herbal medicines.
abstract: Metformin is one of the most common adulterants found in anti-diabetic dietary supplements and herbal medicines. An analytical method based on hydrophilic interaction chromatography (HILIC)/tandem mass spectrometry was developed and validated for the determination of metformin in dietary supplements and herbal medicines. Sample preparation involved solid phase extraction of the analyte using Plexa PCX cartridges, and cleanup by a primary-secondary amine (PSA) adsorbent for minimization of the matrix effect. Chromatographic separation was performed on a HILIC column using a mixture of 0.025 mol/L ammonium formate (pH 3) and acetonitrile (18:82, v/v) as the mobile phase at flow rate of 0.25 mL/min. The method was validated in four matrices (capsules, honeyed pills, tablets and oral solutions). The method had a good linear range (5-500 ng/mL), and the overall precision and accuracy ranged from 2.2% to 9.9% and 4.6% to 11.3%, respectively.
authors: Center for Disease Prevention and Control of Guangdong Province, Guangzhou 510300, China; College of Chemistry and Molecular Sciences, Wuhan University, Luojiashan, Wuhan 430072, China. Electronic address: wxmdwb927@126.com.
authors: Ximei
authors: X
authors: Wu
authors: Center for Disease Prevention and Control of Guangdong Province, Guangzhou 510300, China.
authors: Binghui
authors: B
authors: Zhu
authors: Center for Disease Prevention and Control of Guangdong Province, Guangzhou 510300, China.
authors: Lin
authors: L
authors: Lu
authors: Center for Disease Prevention and Control of Guangdong Province, Guangzhou 510300, China.
authors: Weixiong
authors: W
authors: Huang
authors: College of Chemistry and Molecular Sciences, Wuhan University, Luojiashan, Wuhan 430072, China. Electronic address: dwpang@whu.edu.cn.
authors: Daiwen
authors: D
authors: Pang
mesh_terms: D002853:Chromatography, Liquid / Q000379:methods*; D019587:Dietary Supplements / Q000032:analysis*; D029001:Herbal Medicine / Q000379:methods*; D057927:Hydrophobic and Hydrophilic Interactions; D008687:Metformin / Q000032:analysis* / Q000737:chemistry; D052616:Solid Phase Extraction / Q000379:methods*; D053719:Tandem Mass Spectrometry / Q000379:methods*
chemical_list: D008687:Metformin
keywords: Dietary supplements; HILIC/MS/MS; Herbal medicines; Metformin; Primary–secondary amine adsorbent; Solid phase extraction