Preparation and intestinal absorption of Panax notoginseng saponins chitosan nanoparticles / 中国中药杂志

In this experiment, Panax notoginseng saponins chitosan nanoparticles(PNS-NPs) were prepared by self-assembly and their appearance, particle size, encapsulation efficiency, drug loading, polydispersity index(PDI), Zeta potential, and microstructure were characterized. The prepared PNS-NPs were intact in structure, with an average particle size of(209±0.258) nm, encapsulation efficiency of 42.34%±0.28%, a drug loading of 37.63%±0.85%, and a Zeta potential of(39.8±3.122) mV. The intestinal absorption of PNS-NPs in rats was further studied. The established HPLC method of PNS was employed to investigate the effects of pH, perfusion rate, and different drugs(PNS raw materials, Xuesaitong Capsules, and PNS-NPs). The absorption rate constant(K_a) and apparent permeability coefficient(P_(app)) in the duodenum, jejunum, ileum, and colon were calculated and analyzed. As illustrated by the results, the intestinal absorption of PNS-NPs was increased in the perfusion solution at pH 6.8(P<0.05), and perfusion rate had no significant effect on the K_a and P_(app) of PNS-NPs. The intestinal absorption of PNS-NPs was significantly different from that of PNS raw materials and Xuesaitong Capsules(P<0.05), and the intestinal absorption of PNS-NPs was significantly improved.

Research advances in the effect and utilization of protein corona on the circulation of nanoparticles in vivo / 药学学报

Nanoparticles have better applicability in the detection, treatment of cancer and various difficult diseases, but mononuclear phagocytosis system can seriously shorten the time of nanoparticles in vivo circulation, reduce the drug efficacy. The protein crown formed on the surface of the nanoparticle after entering the body can change its surface properties, interfere with the recognition of phagocytes, and thus affect its circulation time in vivo. This article outlines the general composition and formation process of protein crowns. It also summarizes the influence of the physical and chemical properties of nanoparticles, such as particle size, surface charge, hydrophilicity and surface materials on the formation of protein crowns. The protein crown affects the circulation of nanoparticles in vivo, mainly because the adsorbed opsonic protein promotes cell phagocytosis. Therefore, we also introduce the method of using protein crowns to promote the long circulation of nanoparticles in vivo. By designing appropriate physical and chemical properties, surface modification, and directed design of protein crowns, the adsorption of proteins on the surface of nanoparticles can be reduced. Therefore, it can reduce the clearance of nanoparticles in the mononuclear phagocytic system (mainly the phagocytes of the liver and spleen), and achieve the goal of long circulation of nanoparticles in the body.