Preparo e aplicação de dispositivos de liberação transdérmica de fármacos utilizando amido catiônico e dialdeído amido

Abstract

Starch derivatives have attracted the attention of several researchers for conferring new physicochemical and biological properties to biomaterials developed from them. However, aspects related to the type of biomaterial prepared and its target application still need to be investigated. Based on this, this doctoral thesis describes the synthesis of two starch derivatives and explores their use in the preparation of biomaterials to act as transdermal drug delivery systems (SLTF). The first synthesized derivative was cationic starch (CSt), which had a degree of substitution of 0.7. CSt was used in the fabrication of polymeric films together with polyvinyl alcohol (PVA) and chondroitin sulfate (ChS) to serve as carriers for the drug methotrexate (MTX), used in the treatment of rheumatoid arthritis (RA). Characterization analyses demonstrated the interaction between the polymers; however, the interaction with the drug was minimal. The sample containing 5 m/m-% of MTX, which allowed drug penetration into skin extracts, showed the greatest potential for testing in vivo. Using an animal model, it was found that the selected film for these tests attenuated and treated the symptoms of RA when compared to the control group treated orally with free MTX. The second synthesized derivative was dialdehyde starch (DAS), obtained by an oxidation reaction, with an aldehyde group content of 77%. Crosslinking of these groups with amino groups of gelatin (Gel) via Schiff base formation was explored in the fabrication of films by casting and hydrogels by 3D printing, which were tested as carriers for the drug hydrocortisone (HC), used in the treatment of atopic dermatitis (AD). Both materials demonstrated the ability to control drug release through a transdermal delivery route, and using an AD animal model, it was observed that both the film and hydrogel are effective in treating the symptoms of this chronic skin disease. The use of these biomaterials can mitigate potential adversities associated with the topical use of HC. In summary, the studies presented here offer new opportunities for the manufacturing and employability of starch derivative-based biomaterials for use as SLTF.