The Study On Insoluble Silk Microneedle

The blend film and microneedle of silk fibroin/sugar were prepared by blendingregenerates silk fibroin solution and sugar solution. This paper studies on the relationshipbetween preparation conditions and physic-chemical properties, trying to provide a kind ofnew materials for biomedical fields and a preparation foundation for the application.The blend films were prepared by casting SF/sugar mixture solution on a polyethyleneplate, mannose, glucose, sorbose, glucosamine were choose as additive. Theconformational structure of blend films was characterized by XRD. The water solubility,broken tensile strength, broken elongation and light transmittance of blend films weretested and analyzed. Results indicated that sugar induced the structure of silk fibroin fromrandom coil to Silk I structure. With the increasing of the content of sugar, thecrystallization of sugar was high. The results also showed that saccharides can solve theproblem of solubility of silk film. Mannose, glucose and sorbose can improve SF film’sbrittleness. The flexibility of the blend films was very good, with the increase of thecontent of sugar. Elongation at break was increased at first and then gradually decline, andbroken tensile strength was decreased. Glucosamine/SF blend films remained the brittlecharacteristics of pure SF films. The compatibility between silk fibroin and additives caninfluence the light transmittance. With the compatibility of sugar and SF increasing, thelight transmittance was increased. With the content of sugar increased, the lighttransmittance was declined. The light transmittance of blend films can satisfy therequirements of the application of human cornea when the content under3/10, which wasexpected to be the cornea repair material. Biodegradability and biocompatibility of blendfilms were examined. The results showed that the SF/sugar blend films can keep fibroinmaterials unique biological characteristics due to non-toxic of sugar.With polydimethylsiloxane (PDMS) as the base, microinjection mold was preparedused laser drilling process. Two kinds of indissolvable silk microneedle were prepared bythis mold. One was made of blending SF solution and glucosamine solution. Another microneedle was prepared by the SF hydrogel, which was prepared by ultrasonicoscillations. The pierced property, swelling property and degradation performance of twokinds of microneedles were tested. The results showed that as two kinds of microneedlescan conform to the requirements. Finally, the results of drug release properties showed thatthe drug release performance of microneedle was better than film. And the gel microneedlewas better than that of glucosamine/SF microneedles.