The present study describes the development of a chlorhexidine long-term drug delivery system using starch as a biodegradable polymer base. Three batches of thermoplastic starch films, containing starch particles/nanoparticles and chlorhexidine (CHX), were manufactured by casting. Morphological characterization showed an irregular surface with particles incorporated with chlorhexidine agglomerated in a starch matrix. Nanoindentation showed that the control film (without chlorhexidine) presented a more plastic and rigid behavior in relation to the films containing CHX. CHX was partially bounded to starch and prevented starch crystallization. Starch nanoparticles formed by precipitation were observed through transmission electron microscopy. By incorporating CHX into the solution, the nanoparticles presented different morphology, suggesting absorption of the drug. In vitro drug release was observed for 21 days by UV–vis spectrophotometry and released CHX amounted up to 19 mg/100 ml. Films presented microbiological potential for inhibiting Staphylococcus aureus growth as evaluated by the disk diffusion test in agar. It has been concluded that the developed film met the main requirements for a drug delivery system and that it is possible to be produced from a simple, cheap and reproduceable process.

本研究描述了使用淀粉作为可生物降解的聚合物基质的洗必泰长期药物输送系统的开发。通过流延制造三批包含淀粉颗粒/纳米颗粒和洗必泰（CHX）的热塑性淀粉薄膜。形态学表征显示不规则表面，其中结合有洗必泰的颗粒聚集在淀粉基质中。纳米压痕表明，与含CHX的膜相比，对照膜（不含氯己定）具有更强的塑性和刚性。CHX与淀粉部分结合，可防止淀粉结晶。通过透射电子显微镜观察到由沉淀形成的淀粉纳米颗粒。通过将CHX掺入溶液中，纳米颗粒呈现出不同的形态，建议吸收药物。紫外可见分光光度法观察了21天的体外药物释放，释放出的CHX高达19 mg / 100 ml。薄膜具有抑制微生物的潜力通过在琼脂中的纸片扩散试验评估金黄色葡萄球菌的生长。已经得出的结论是，显影的胶片满足药物输送系统的主要要求，并且可以通过简单，廉价和可复制的方法生产。