SIMULTANEOUS DETERMINATION OF PALMATINE AND BERBERINE USING CUCURBIT[7]URIL AS MOBILE PHASE ADDITIVE BY HPLC

Abstract

A simple and sensitive high performance liquid chromatography-fluorescence detector (HPLC-FLD) method was developed for simultaneous determination of palmatine (PAL) and berberine (BRH). The method is based on the enhancement of the fluorescence of PAL and BRH in aqueous solution in the presence of cucurbit[7]uril (CB[7]). The chromatographic resolution of PAL and BRH was performed on a SymmetryShieldTM RP 18 column with CB[7] as the mobile phase additive. The composition of the mobile phase was (50/50, v/v) absolute methanol/0.05% (v/v) triethylammonium acetate buffer (pH 4.1) with 1.25 × 10⁻⁴ M CB[7] at a flow-rate of 0.5 mL · min⁻¹. The linear ranges of PAL and BRH were 3–230 and 2–220 ng · mL⁻¹, with the regression equations of Y = 594248 + 7.56 × 10⁴X (R = 0.9993), Y = 811028 + 6.32 × 10⁴X (R = 0.9995), respectively. The limits of detection for PAL and BRH were 1 and 0.7 ng · mL⁻¹, respectively, with fluorescence detection at an excitation wavelength of 347 nm and an emission wavelength of 495 nm. The sensitivity of the proposed method was almost equal to previous liquid chromatography-mass spectroscopy method. The proposed method was applied to determine PAL and BRH in human plasma and Jinji capsules. The HPLC-FLD method was sensitive and convenient.

Keywords:

• additive
• berberine
• cucurbit[7]uril
• fluorescence detection
• HPLC
• palmatine

ACKNOWLEDGMENTS

This work was supported by the Research Fund for the Doctoral Program of Higher Education of China (No. 20091404110001) and Shanxi Province's innovation projects Fund for the postgraduates of China (No. 20103063). Helpful suggestions by anonymous referees are also gratefully acknowledged.

Notes

^a Average of six determination.

^a Average of six determination.

The tabulate values of t and F at the 95% confidence limit are t = 2.23 and F = 5.05.

^a Average of six determination.