[Determination of baicalin and chlorogenic acid in yinhuang granule by capillary electrophoresis].

Yinhuang Granule is a kind of complex formulae made up of extract of Flos lonicerae and that of Radix scutellariae, of the fuctions of dispelling wind-heat to reduce fever, detoxicating, relieving inflammation, promoting urination and tranquilizimg the mind and can be applied to upper respiratory tract infection and tonsillitis. Baicalin and chlorogenic acid are referred to main effective components of it. In this paper, the separation and determination of baicalin and chlorogenic acid in Yinhuang Granule by capillary electrophoresis is described. The experimental conditions are stated as follow: separation column: bare fused-sillica capillary (50 microns i.d., 370 microns o.d., total length 47 cm, 40 cm from the inlet to UV detector); electrolyte: 25 mmol/L borax, pH 8.5; detection wavelength: 310 nm; sampling: 17 kPa.s; running voltage: 25 kV, polarity from anode (inlet) to cathode (outlelt); temperature: 25 degrees C; internal standard: p-nitrobenzoic acid. The linear ranges of determination for baicalin and chlorogenic acid were 160-960 mg/L(r = 0.9993, RSD = 1.76%-2.33%) and 80-960 mg/L(r = 0.9989, RSD = 1.07%-2.51%), respectively. The recoveries of baicalin and chlorogenic acid were (102.09 + 1.74)% (RSD = 1.71%, n = 6) and (99.81 + 3.11)% (RSD = 3.12%, n = 6). The method is simple, fast and accurate. It can be used for the quality control of Yinhuang Granule and its related Chinese medicines.