Determination of 5-Hydroxymethylfurfural, NƐ-(Carboxymethyl)Lysine and NƐ-(Carboxyethyl)Lysine in 16 Traditional Chinese Medicine Injections Based on HPLC and UPLC-MS/MS
Abstract Background: Traditional Chinese medicine injections (TCMIs) are widely applied to treat many chronic diseases. However, product quality problems occur occasionally due to unknown constituents in TCMIs. 5-hydroxymethylfurfural (5-HMF), NƐ-(carboxymethyl)lysine (CML) and NƐ-(carboxyethyl)lysine (CEL) are three compounds generated during food and Chinese medicinal herb processing and may be harmful to human health. Methods: In this study, the contents of 5-HMF, CML and CEL were determined by high-performance liquid chromatography (HPLC) and ultra-performance liquid chromatography (UPLC). For 5-HMF, the separation was performed on a Hypersil ODS2 column (250 mm×4.6 mm, 5 µm), and the column temperature was set at 30℃. The mobile phase was composed of water-methanol (95:5) at a flow rate of 1.0 mL/min. For CML and CEL, separation was performed on a CORTECS HILIC UPLC column (2.1 mm×50 mm, 1.6 µm), and the column temperature was set at 40℃. The mobile phase was composed of acetonitrile-water (3:7) at a flow rate of 0.3 mL/min. Multiple-reaction monitoring mode was employed for analyte determination with positive ionization. Results: The contents of 5-HMF in 16 TCMIs varied from 0.19 to 74.98 µg/mL, with a larger variation than the contents of CML and CEL. The Ciwujia injection had the highest content of 5-HMF, and the Qingkailing injection had the lowest 5-HMF content. The contents of CML and CEL among these TCMIs were 0.51-7.32 ng·mL-1 and 0.38-5.49 ng·mL-1, respectively. The contents of CML and CEL in the Shuxuetong injection were much higher than in the others.Conclusions: The methods established in this study were simple, rapid and accurate and could provide a theoretical basis for the quality evaluation of TCMIs.