负载旋覆代赭汤的白及多糖胃漂浮剂的制备、表征及其胃肠道滞留性能评价OA

[Objective]To prepare a Bletilla striata polysaccharide gastric floating agent loaded with Xuanfu Daizhe Tang extract(XDT@BSP-FS)for gastroesophageal reflux induced nausea and vomiting,and to evaluate its floating and gastric retention properties.[Methods]A Bletilla striata polysaccharide(BSP)-glyceryl monooleate(GMO)hydrogel framework(BSP-FS)was prepared via a mixed swelling method,followed by loading with Xuanfu Daizhe Tang to yield XDT@BSP-FS.The floating performance,microstructure,physicochemical properties,rheological and mechanical properties,in vitro digestion behavior,and in vivo retention behavior were systematically evaluated.[Results]XDT@BSP-FS exhibited immediate floating(0 s),formed a floating layer with a thickness of 0.52 cm,and maintained stable buoyancy for over 8 h.Structural characterization revealed the formation of a dense,lamellar porous network within XDT@BSP-FS.Thermal analysis(DSC)and Fourier transform infrared spectroscopy(FT-IR)indicated that Xuanfu Daizhe Tang existed within the BSP-FS framework predominantly through physical interactions.At equivalent doses,XDT@BSP-FS demonstrated superior mechanical toughness compared with the commercially available product Gaviscon®.In vivo and ex vivo fluorescence imaging demonstrated that,following intragastric administration of XDT@BSP-FS,the gastrointestinal fluorescence signal persisted for more than 4 h in vivo,and obvious fluorescence was still detectable at 6 h ex vivo.By contrast,the fluorescence signal in the indocyanine green(ICG)aqueous solution group was already markedly attenuated at 4 h.[Conclusion]XDT@BSP-FS exhibited rapid flotation,prolonged floating duration,and favorable in vivo retention behavior,providing a reference for the development of gastroretentive drug delivery systems for gastroesophageal reflux related diseases.