Lin Zhang, Xiaodong Gu, Hongwei Wei, Xigang Liu, Pei Liu, Jinhua Chang, Qiang Fu, Cuizhe Liu
In the present study, we aimed to prepare rhubarb total anthraquinones oral colon-specific drug delivery granules (RTA-OCDD-GN) for delivering rhubarb free anthraquinones to colon. RTA-OCDD-GN was successfully prepared through a double-layer coating process using chitosan as an inner layer and Eudragit S100 as an outer enteric coating layer. The pharmacodynamics and toxicological results showed that RTA-OCDD-GN could produce considerable purgative efficacy with half dosage of rhubarb medical material (RMM), and significantly reduce the nephrotoxicity of anthraquinones compared with RMM. The comparative pharmacokinetics results in vivo gave a preliminary explanation to the mechanism of toxicity attenuation of RTA-OCDD-GN. Taken together, the oral colon-specific delivery system was a useful media to achieve the effect-enhancing and toxicity attenuation of orally administrated rhubarb total anthraquinones.