Study On Sustained - Release Drug Delivery System Of Traditional Chinese Medicine Based On New Carrier Of Hydrogel Composite Fabric

Hydrogels swell in water, but not dissolve, are polymeric networks with three dimensional structure, they have the capacity of imbibing great amount of water or biological fluids. Recently, there appeared a kind of "intelligent or smart" hydrogel which exhibited rapid volume phase transition in response to slight changes in external stimuli such as temperature, pH, light, ionic strength, and solvent type, etc. Since hydrogel contain large water content, they are widely used in the fields of drug delivery system, wound dressing and tissue engineering. However, noticeable defects inherent to pure PNIPAAm hydrogels are obvious syneresis and poorly mechanical strength taking place with elevated temperature above LCST, which limit their wide application to a certain extent.In the present studies, a poly(N-isopropylacrylamide)/alginate copolymer hydrogel was developed by graft copolymerization under the condition of ceric ammonium nitrate, which was grafted on the nonwoven fabric to construct hydrogel-grafted-fabrics (HGFs) system. Water soluble matrine, and poorly soluble berberine hydrochloric nanoparticles prepared by high-pressure homogenization method were incorporated in the HGFs according to the physical swelling adsorption technology at lower temperature to achieve two HGFs loading with drug. Some characteristics including drug loading efficiency, surface morphology, swelling degree, drug release rate were investigated, respectively. And the anti-bacterial and anti-inflammatory activities were also studied. Methodology results showed that matrine had a linear relationship in the range of22～220μg·mL-1(r=0.9998, n=6). And the berberine hydrochloric was20.02～200.2μg.mL-1(r=0.9999, n=6). The drug loading efficiency of matrine and berberine hydrochloric were calculated from the equation:Leff=W1/Wd×100%,and the results were2.5%and0.8%, respectively. FT-IR revealed that HGFs was developed by grafting hydrogel that prepared under copolymerization of N-isopropylacrylamide and alginate to the fabric. Then matrine and berberine hydrochloric were both embedded into the matrix of HGFs, but not on the surface. SEM showed that a thin hydrogel layer was formed on the surface of nonwoven fibers. Both of the two drug particles were uniformly dispersed in the HGFs. The swelling kinetics at different temperatures represented that HGFs was reversible temperature-sensitive with the water absorbing and holding capacity. The lower critical solution temperature (LCST) was about32℃. It possessed excellent water absorbing and holding capacity with the swelling ratio of63.48%～126.84%. The in vitro drug release kinetics from swollen HGFs based network demonstrated that cumulative release of matrine from HGFs in24h and72h were87.72%,95.09%. But, the berberine nanoparticles were46.52%and85.2%. In vitro pharmacodynamic test showed that HGFs loaded with matrine could act on the inflammation, and HGFs embedded in berberine nanoparticles could promote wound healing and prevent infection. HGFs could be used as a promising sustained drug delivery system for active ingredients of traditional Chinese medicine and provided a new choice for wound dressing.