Baicalin,silver titanate,Bletilla striata polysaccharide and carboxymethyl chitosan in a porous sponge dressing for burn wound healing

Objective This study tests the efficacy of Bletilla striata polysaccharide(BSP),carboxymethyl chitosan(CMC),baicalin(BA)and silver titanate(ST)in a wound dressings to fight infection,promote healing and provide superior biocompatibility.Methods The antibacterial activity of BA and ST was evaluated in vitro using the inhibition zone method.BA/ST/BSP/CMC porous sponge dressings were prepared and characterized.The biocompatibility of BA/ST/BSP/CMC was assessed using the cell counting kit-8 assay.The therapeutic effect of BA/ST/BSP/CMC was further investigated using the dorsal skin burn model in Sprague-Dawley rats.Results The wound dressing had good antibacterial activity against Escherichia coli and Staphylococcus aureus through BA and ST,while the combination of BSP and CMC played an important role in promoting wound healing.The BA/ST/BSP/CMC porous sponge dressings were prepared using a freeze-drying method with the concentrations of BA and ST at 20 and 0.83 mg/mL,respectively,and the optimal ratio of 5%BSP to 4%CMC was 1:3.The average porosity,water absorption and air permeability of BA/ST/BSP/CMC porous sponge dressings were measured to be 90.43%,746.1%and 66.60%,respectively.After treatment for 3 and 7 days,the healing rates of the BA/ST/BSP/CMC group and BA/BSP/CMC group were significantly higher than those of the normal saline(NS)group and silver sulfadiazine(SSD)group(P<0.05).Interleukin-1βexpression in the BA/ST/BSP/CMC group at 1 and 3 days was significantly lower than that in the other three groups(P<0.05).After being treated for 3 days,vascular endothelial growth factor expression in the BA/BSP/CMC group and BA/ST/BSP/CMC group was significantly higher than that in the NS group and SSD group(P<0.05).Inspection of histological sections showed that the BA/ST/BSP/CMC group and BA/BSP/CMC group began to develop scabbing and peeling of damaged skin after 3 days of treatment,indicating accelerated healing relative to the NS group and SSD group.Conclusion The optimized concentration of BA/ST/BSP/CMC dressing was as follows:6 mg BSP,14.4 mg CMC,0.5 mg ST and 12 mg BA.The BA/ST/BSP/CMC dressing,containing antibacterial constituents,was non-cytotoxic and effective in accelerating the healing of burn wounds,making it a promising candidate for wound healing.

Bletilla striata polysaccharide modified collagen fiber composite sponge with rapid hemostasis function

Emergencies often result in uncontrollable bleeding, which is thought to be the leading cause of death at the scene of the injured. Among various hemostasis scenarios, collagen fiber (CF) is gradually replacing traditional hemostatic materials due to its superior properties and ease of sourcing from animals. Herein, we use CF and the natural herba-ceous Bletilla striata as raw materials to prepare a collagen fiber-oxidized Bletilla striata composite hemostatic sponge (CFOB). During the cross-linking process, the triple helix structure of collagen stays intact, and its porous three- dimensional network structure brings excellent bulkiness and water absorption properties. Experiments show that the optimal amount of sponge CFOB-10, namely oxidized Bletilla striata polysaccharide 0.5 mg/mL and CF 5 mg/mL, only needed 25 ± 4.06 s for hemostasis time in the rat liver hemorrhage model. In addition, CFOB meets the safety performance requirements of cytotoxicity classification standard 0. Therefore, the optimal amount of CFOB is an excel-lent new hemostatic material with application potential.

Preparation of Colon‐specific and Synchronous Release Pellet Containing Total Alkaloids of Sophora alopecuroides

Objective To deliver multiple component drugs to colon site and sustain a synchronous release for better therapeutic effect. For achieving this purpose, colon specific pellet containing total alkaloids of Sophora alopecuroides （TASA） was prepared. Methods The pellet was prepared by extrasion-spheronizing and subsequently coated with three layers of two polymers. Results The pellet core consisted of 40% TASA, 1：2 in ratio of Bletilla striata polysaccharide （BSP）, an enzyme-degradable material, to microcrystalline cellu{ose （MCC）, filler, and 1% CMC-Na solution as binder by optimization. Concerning of the three coated layers, the outer layer was coated with Eudragit RS30D for controlling drug release in colon, the intermediate layer and the inner layer were coated with same polymer, Eudragit $100, for preventing drug release in upper gastrointestinal tract, which required 23.2%, 21.7%, and 9.3% weigh gain, respectively. The coated pellets released 1.20% of sophoridine and 1.98% of matrine in media mimicking the stomach condition for 2 h, and 23.88% of sophoridine and 22.91% of matrine in media mimicking the intestine for 3 h and finally 90.25% of sophoridine and 89.94% of matrine in colonic conditions within 24 h, And the similarity factor f2 of sophoridine and matrine of release curve for investigated formulation was internal in （50-100） and 〉 80, demonstrating that sophoridine and matrine in formulation achieved a synchronous release. Conclusion The coated pellets achieve a certain colon-specific release and synchronous release.