| Currently,clinical protein peptide drugs are usually administered by injection,but the pain brought by the injection to the user greatly reduces their compliance with the injection.As a new transdermal drug delivery method,microneedle has emerged at the right moment.Because of its advantages of dual drug release combining subcutaneous injection and skin patch,as well as its characteristics of high efficiency,painlessness and safety,its application field is more and more extensive.According to the different way of drug loading,it can be divided into solid microneedles,coated microneedles,hollow microneedles and dissolving microneedles.However,different types of microneedles have different degrees of problems in economy,biocompatibility,mechanical strength,preparation and preservation.In recent years,dissolving microneedles have the advantages of great biocompatibility,simple equipment and high drug loading.Preparation of dissolving microneedles with biodegradable polymer materials,such as: polylactic acid(PLA),polyglycolic acid(PGA),polylactic acid-polyglycolic acid(PLGA)and hyaluronic acid(HA),maltose,chitosan and carboxymethyl cellulose(CMC)etc.,especially suitable for transdermal drug delivery of protein polypeptide drugs,but because of its higher cost to make microneedles mold and complicated process,in the process of preparation of auxiliary centrifugation,heating and other methods may lead to the decline of the drug stability and the loss of the raw material,which will make its application limitated.Therefore,in this study,combined with the reported literature and the existing facilities in the laboratory,the microneedles mold with complete structure was prepared for the first time by using epoxy resin as the material and controlling the temperature of its curing stage,and the microneedles mold with complete structure was prepared under the negative pressure at the room temperature.The preparation process was simple and mild.Then work in the small peptide P-WH that makes in the lab early de novo design for the active components,whicht ability as hEGF is to repair the aging skin,and blended with the natural moisturizing factor HA,then preparating the P-WH-HA dissolving drug-loaded microneedles.By FITC fluorescence signal in the microneedles with its antioxidant activity detection,preliminary proves that P-WH drugs in microneedles can be evenly distributed and it has greatstability;Accordiing to construct the model of the mice’s skin aging by UV irradiation,and the intuitive analysis of mice back wrinkles,the skin elasticity and thickness proved that the repair effect of P-WH-HA dissolving drug-loaded microneedles capsules on aging skin is better than the direct application,and there is no irritation or allergy to the skin of mice,so it has certain safety and mechanical strength.Through acute the oral toxicity test,cytotoxicity and hemolytic test,it is further verified that P-WH-HA microneedles has great safety,so it has great development prospects in the field of medical beauty such as prevention,improvement and repair of skin aging. |
