RESUMO
OBJECTIVE: To develop an HPCE method of tetramethylpyrazine hydrochloride in rat plasma using pyramide as the internal standard. METHODS: The separation was performed on a fused-silica uncoated capillary with an inner diameter (ID) of 75 μm, an effective length of 50 cm and a total length of 60 cm. The optimum HPCE conditions were as follows: 100 mmol·L-1 SDS-30 mmol·L-1 sodium tetraborate solution (40:60) was used as the background electrolyt, the samples were injected at the anodic end at 0.5 psi for 6 s, separation voltage was 20 kV at positive power, capillary temperature was 20°C, and detection wavelength was 295 nm. RESULTS: The linear range was 1.12-286.72 mg·L-1(r=0.9996), and the inter-day and intra-day precisions expressed as RSDs were less than 4.21% and 4.74%, respectively. The average recoveries were 91.22%-97.48%, and the limit of detection was 0.16 mg·L-1. CONCLUSION: This method is rapid and accurate to quantify tetramethylpyrazine hydrochloride in rat plasma.
RESUMO
<p><b>OBJECTIVE</b>To develop a method for analyzing the chemical compositions of Gegen and Fenge extracts using high-performance capillary electrophoresis (HPCE).</p><p><b>METHODS</b>Using HPCE/DAD, the chemical composition of the extracts was analyzed with the buffer solution of 40 mmol/L borax containing 16.7% methanol, with injection pressure at 137.9 kPa for 5 s, separation voltage at 25 kV in 0-5 min time range and at 22 kV in 5-25 min time range, and the temperature of the capillary of 20 degrees celsius.</p><p><b>RESULTS AND CONCLUSION</b>The method for analysis of Gegen and Fenge extracts was established, which identified puerarin and daidzein as the two major components. This simple and rapid analysis method can be used for Gegen and Fenge extract fingerprinting.</p>