The Application Of Transdermal Drug Delivery Technology Of Polymer Microneedles In Psoriasis

Psoriasis is a chronic inflammatory disease with the properties of high incidence and easy recurrence.The pathogenesis of this disease is still unclear.The disease has a long onset period and is difficult to cure,which puts stress and pain on the patient's spirit and body and has a great impact on the patient's quality of life.At present,local drug therapy is widely used.The drugs used for treatment are anthracene,corticosteroids,calcipotriol,and methotrexate.However,the thickening stratum corneum of psoriasis causes low absorption rate of drugs.In order to solve this problem,the main research contents are as follows:1.In this article,imiquimod was applied to BALB/c back and ears to successfully model psoriasis.Solid polymer microneedles(MNs)of different heights were prepared by hot pressing method.The dorsal skin and ears of mice were pretreated with solid polymer MNs and then treated with calcipotriol ointment.The compare results of phenotype of mice skin,PASI score,spleen coefficient,epidermal thickness and inflammatory cell infiltration in tissue showed that solid polymer MNs pretreatment of psoriatic mice skin has better improvement effect.2.The large solid polymer MNs plate was successfully fabricated by hot-press method.The MN plate with uniform thickness and good transparency was prepared by optimizing the upper cover plate,preheating time,hot pressing time,pressure and material spreading pattern.The MN plate was cut to required size by adjusting the energy and speed of the laser.The cut MNs were sterilized and stored for later use.The prepared MN plates were heated in an oven at 105?.The color of MN plates changed from transparent to milky white.3.The coated MNs were successfully fabricated with capillary,flip dipping method and floating dipping method.The coated MNs prepared by the latter two methods have uniform drug loading.Compared with the two dipping methods,the floating dipping method is simple and can be further studied.In order to reduce the waste of coating solution in the preparation process,the limit plate was immersed in a hydrophobic solution to prepare a superhydrophobic limit plate and it can be used to successfully prepare coated microneedles.