Hollow Fiber/Solvent Bar Microextraction Coupled with High Performance Liquid Chromatography for Preconcentration and Determination of Tanshinones and Salvianolic Acids in Radix Salvia miltiorrhiza

Abstract

Hollow fiber solvent bar microextraction coupled with high-performance liquid chromatography was developed for the preconcentration and determination of active ingredients in Radix Salvia miltiorrhiza. These ingredients include dihydrotanshinone I, cryptotanshinone, tanshinone I, tanshinone IIA, salvianolic acid B, danshensu, and protocatechuic aldehyde. To evaluate the technique, seven compounds of varying polarity were used as model analytes, and a polyvinylidene fluoride hollow fiber (1.0 cm) with octanol (2 µL) was used as microextraction bar. The extraction conditions, including the identity of the hollow fiber, organic solvent, pH, salt addition, agitation speed, extraction time, and volume, were investigated and optimized. The extraction mechanism was analyzed and verified. The two main parameters, extraction recovery and enrichment factor, were obtained. Under the most favorable conditions, the enrichment factors of the analytes were 0.7–612, the limits of detection were below 1.11 ng mL⁻¹, and the recoveries were between 95.4% and 101.3%. Thus, hollow fiber solvent bar microextraction is simple, rapid, and practical with a wide range of potential applications.

Keywords:

• High-performance liquid chromatography
• Hollow fiber solvent bar microextraction
• Radix Salvia miltiorrhiza
• Salvianolic acids
• Tanshinones

Acknowledgments

We thank the Nature Science Foundation of Shanxi Province (No. 2011011035-2) and the Program for the Top Science and Technology Innovation Teams of Higher Learning Institutions of Shanxi Province, China (2011) and the Innovation Foundation of Shanxi Medical University (No. C01201010) for financial support.