Preparation and performance evaluation of carboxymethyl chitosan/oxidized glucomannan/panax notoginseng compound sponge dressing for chronic wound / 中国组织工程研究

BACKGROUND: Previous studies have shown that carboxymethyl chitosan/oxidized glucomannan composite sponge can be used as an excellent substrate for drug-loaded chronic wound dressings. OBJECTIVE: To prepare carboxymethyl chitosan/oxidized glucomannan/Panax notoginseng composite sponge and evaluate its physical and chemical properties and biocompatibility. METHODS: Oxidized glucomannan was prepared by sodium periodate oxidation. Panax notoginseng saponins were extracted from Panax notoginseng powder. Carboxymethyl chitosan and oxidized glucomannan were first added as mixed raw materials, and then added separately to account for mixing system 2%, 6%, 10% of Panax notoginseng saponins. Freeze-drying method was used to prepare carboxymethyl chitosan/oxidized glucomannan/Panax notoginseng composite sponge. Scanning electron microscope was utilized to observe the microstructure of the composite sponge. Porosity, steam permeability, total saponin release rate of Panax notoginseng, cell compatibility, antibacterial properties and acute systemic toxicity were detected. RESULTS AND CONCLUSION: (1) Scanning electron microscope showed that there were many pores in the composite sponge that were full and evenly distributed. The total saponins of Panax notoginseng were stably and evenly attached to the inner walls and joints of the pores of the sponge. (2) As the proportion of total saponins of Panax notoginseng increased, the water absorption rate, porosity, and steam permeability gradually increased. (3) The vast majority of the total saponins of Panax notoginseng in the three kinds of composite sponges could be efficiently released in 13 hours in vitro. (4) Within 3 days after in vitro culture, the proliferation rate of fibroblasts was more than 95%. (5) Three kinds of compound sponges have an inhibitory effect on E. coli and Staphylococcus aureus, but do not have acute systemic toxicity. (6) The results show that carboxymethyl chitosan/oxidized glucomannan/Panax notoginseng composite sponge is expected to be an excellent medical chronic wound dressing.

Hemostatic efficacy of the complex sponge and drug-loaded complex sponge / 中华创伤杂志

Objective To evaluate the hemostatic efficacy of complex sponge and drug-loaded complex sponge on hepatic and splenic wounds in rabbits. Methods Complex sponge was prepared by means of cross-linking and lyophilization. Then, the sponge was immersed into the tranexamic acid solution and lyophilized to obtain the drug-loaded sponge. The complex sponge and drug-loaded complex sponge were respectively used on the hepatic and splenic wounds of rabbits to observe the bleeding time and blood loss under normal and liquemine anticoagulation respectively. The gelatin sponge and the chitosan sponge were used as controls. Results Under normal condition, the hemostatic time and blood loss of the complex sponge was decreased obviously compared with the gelatin sponge ( P＜ 0. 01 ) and compared with the chitosan sponge ( P ＜ 0. 05 ). Posterior to liquemine anticoagulation, the hemostatic time was increased obviously in the gelatin sponge but showed no difference for the chitosan sponge and the complex sponge. Compared with complex sponge, the hemostatic efficacy of the tranexamic acid-loaded complex sponge was improved markedly for normal rabbits. While the hemostatic efficacy showed no significant change for rabbits with coagulation disorders, when there was no linear relationship between the hemostatic efficacy and the content of tranexamic acid. Conclusions The hemostatic efficacy of the complex sponge and the drug-loaded complex sponge surpass obviously that of the gelatin sponge, especially for the rabbits with coagulation disorders.

Preparation and in vitro/in vivo pharmacological studies of bFGF/collagen composite sponge / 中国药科大学学报

Aim: To investigate a new type wound dressing,basic fibroblast growth factor(bFGF)/collagen com-posite sponge,and conduct its pharmacological studies in vitro and in vivo.Methods: bFGF/collagen composite sponge was prepared using fresh pig skin and bFGF.The sponge's physicochemical properties were studied.MTT assay was used to detect the proliferation effect of the sponge extract on 3T3 cells.Delayed allergy of the sponge was tested for the assurance of its biosafety.Results: Results showed that the physicochemical properties of bFGF/collagen composite sponge with high and low doses of bFGF have no significant difference from those of blank collagen sponge.SDS-page analysis indicated that the composite sponge has apparent strip in 18 kD.It was also found that bFGF/collagen composite sponge was responsible for significant effects on 3T3 cell proliferation in comparison to saline treatement(P <0.01,P <0.05).In the allergy study,during the periods of the induction and stimulation,no allergic reaction was found in bFGF/collagen composite sponge groups with high and low doses of bFGF,while severe reactions and inflammation occurred in positive group(2,4-dinitrochlorobenzene).Furthermore,pathological examination indicated the intact dermal structure and no sign of inflammation.Conclu-sion: The developed sponge has good physicochemical propertis and noticed cellular proliferation without dermal irritation.There is much potential to develop bFGF/collagen composite sponge into a new kind of wound dressing material for clinical use.