Laboratory for the Development and Evaluation of Bioactive Substances, University of Sorocaba, Cidade Universitária, Rod. Raposo Tavares km 92.5, CEP 18023-000 Sorocaba, Sao Paulo, Brazil.
Curr Pharm Biotechnol. 2014;14(12):1036-47. doi: 10.2174/1389201015666140113112323.
Nitrofurazone (NTZ) is usually employed in the topical treatment of infected wounds and lesions of both skin and mucosa. Microencapsulation is a process utilized in the incorporation of active ingredients within polymers aiming at, among other objectives, the prolonged release of pharmaceutical compounds and protection from atmospheric agents (viz. moisture, light, heat and/or oxidation). With the goal of utilizing the microparticles containing encapsulated NTZ in pharmaceutical formulations, one prepared microparticles containing NTZ via ionotropic gelation of sodium alginate. The microparticles were characterized via scanning electron microscopy analyses, Fourier transform infrared spectroscopy (FTIR) analyses, via determination of encapsulation efficiency, and via thermal analyses (both TGA and DSC). The final gel formulation was also characterized rheologically. The extrusion/solidification technique employed to obtain the calcium alginate microparticles with encapsulated NTZ was found to be adequate, and produced an NTZ encapsulation efficiency of ca. 97.8% ± 1.1%. The calcium alginate microparticles thus obtained, with encapsulated NTZ, exhibited an oval shape and hydrodynamic diameters between 500 μm and 800 μm. From the thermal analyses performed, together with information from the infrared spectra, one may conclude that NTZ did not strongly bind to the polymer, which may be favorable for the release of the active ingredient. From the results obtained in the present research effort, one may conclude that the microparticles produced possess the potential to be utilized as carriers for NTZ in pharmaceutical formulations such as gels, ointments, and solutions.
硝呋太尔（NTZ）通常用于感染性伤口和皮肤及黏膜损伤的局部治疗。微胶囊化是一种将活性成分纳入聚合物中的过程，旨在实现药物化合物的缓释和保护，防止大气因素（即水分、光、热和/或氧化）的影响。为了将含有包封 NTZ 的微颗粒应用于药物制剂中，本研究通过海藻酸钠的离子凝胶化制备了含有 NTZ 的微颗粒。通过扫描电子显微镜分析、傅里叶变换红外光谱（FTIR）分析、包封效率的测定以及热分析（TGA 和 DSC）对微颗粒进行了表征。最终的凝胶制剂也进行了流变学表征。用于获得包封 NTZ 的海藻酸钠钙微颗粒的挤出/固化技术被证明是合适的，并且产生了约 97.8%±1.1%的 NTZ 包封效率。因此，获得的含有包封 NTZ 的海藻酸钠钙微颗粒呈椭圆形，水动力直径在 500μm 至 800μm 之间。从进行的热分析以及红外光谱的信息可以得出结论，NTZ 没有与聚合物强烈结合，这可能有利于活性成分的释放。从本研究工作中获得的结果可以得出结论，所制备的微颗粒具有作为药物制剂（如凝胶、软膏和溶液）中 NTZ 载体的潜力。
