Abstract In this study, encapsulation of ursolic acid (UA) in electrosprayed gelatin nanoparticles and structural modification of the particles through adjusting solution properties was carried out. Atomization of a gelatin solution without UA resulted in smooth particles with mean diameter of 570.1 ± 299.3 nm; however, upon the addition of UA, the particles developed with irregular morphologies and the mean diameter increased to 752.3 ± 706.3 nm. Modification of the particle characteristics using sodium dodecyl sulfate and ammonium oxalate resulted in particles with improved morphology uniformity, mean diameter of 702.8 ± 182.8 nm and encapsulation efficiency of ∼87%. FTIR spectra pointed to stabilization of UA in nanoparticles through establishing hydrogen bonds with gelatin molecular chain. XRD patterns showed that upon encapsulation, UA crystalline nature was changed to a more amorphous state. DSC thermograms illustrated that the nanoparticles would be able to maintain stability at the temperatures up to ∼90 °C. Release studies suggested that the encapsulation extended the release period and decelerated the release rate of UA in PBS solution, and improved its bioaccessibility by 945.58% at the end of simulated gastrointestinal tract. The overall results demonstrate the successful enhancement of particle characteristics and also suggest that electrosprayed gelatin nanoparticles could be a suitable carrier for UA.

中文翻译：

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通过电喷雾技术开发、修饰和表征负载熊果酸的明胶纳米颗粒

摘要 本研究通过电喷雾明胶纳米粒子包封熊果酸 (UA) 并通过调节溶液性质对粒子进行结构修饰。雾化不含 UA 的明胶溶液产生平均直径为 570.1 ± 299.3 nm 的光滑颗粒；然而，加入 UA 后，颗粒以不规则的形态发展，平均直径增加到 752.3 ± 706.3 nm。使用十二烷基硫酸钠和草酸铵对颗粒特性进行改性后，颗粒的形态均匀性得到改善，平均直径为 702.8 ± 182.8 nm，包封率约为 87%。FTIR 光谱表明通过与明胶分子链建立氢键来稳定纳米颗粒中的 UA。XRD图谱表明，在封装后，UA 结晶性质变为更无定形的状态。DSC 热谱图表明纳米颗粒能够在高达 90 °C 的温度下保持稳定性。释放研究表明，包封延长了 PBS 溶液中 UA 的释放时间并减慢了释放速率，使其在模拟胃肠道末端的生物可及性提高了 945.58%。总体结果表明粒子特性的成功增强，并且还表明电喷雾明胶纳米粒子可能是 UA 的合适载体。释放研究表明，包封延长了 PBS 溶液中 UA 的释放时间并减慢了释放速率，使其在模拟胃肠道末端的生物可及性提高了 945.58%。总体结果表明粒子特性的成功增强，也表明电喷雾明胶纳米粒子可能是 UA 的合适载体。释放研究表明，包封延长了 PBS 溶液中 UA 的释放时间并减慢了释放速率，使其在模拟胃肠道末端的生物可及性提高了 945.58%。总体结果表明粒子特性的成功增强，也表明电喷雾明胶纳米粒子可能是 UA 的合适载体。