Gastrointestinal distribution of berberine hydrochloride colon-specific tablets taken orally by rats

Objective To study the concentration changes of berberine hydrochloride colon-specific tablets(BH) in gastrointestinal tissue taken orally by rats,and review the release characteristics of BH.Methods After BH(Ф3mm) was given to rats intragastrically,all rats were killed at different time points for collecting gastrointestinal tissue,which were washed and homogenized.The content of BH in gastrointestinal tissue of different segments in rats was determined by HPLC taken palmatine as internal label.The procedure of HPLC was performed on a column of Diamonsil C18(200 mm×4.6 mm,5μm) and the mobile phase was acetonitrile-KH2PO4 solution(0.033 mol/L,pH=3.0,28∶ 72).The flow velocity was 1 mL/min,the temperature was 30℃ and detection wavelength was 345 nm.Results BH showed a good linear relationship at range of 0.05 mg/L-10.00 mg/L(r0.999) and intra-day accuracy was below 11.8% and inter-day accuracy was below 7.9%.The recovery by this method was qualified.BH did not released in the middle and upper segments of the stomach and small intestine,and released in the lower segment of the small intestine,caecum and colon in rats.Conclusion The colon-specific release characteristics of BH are good.