Department of Environmental Engineering, São Paulo State University, Av. Três de Março, 511, Sorocaba, SP 18087-180, Brazil.
Pharm Res. 2011 Aug;28(8):1984-94. doi: 10.1007/s11095-011-0425-6. Epub 2011 Apr 7.
The aim of this work was to investigate the influence of the oily nucleus composition on physico-chemical properties and anesthetic activity of poly (lactide-co-glycolide) nanocapsules with benzocaine.
Nanocapsules containing benzocaine were prepared with three different oily nucleus composition and characterized by mean diameter, polydispersivity, zeta potential, pH and stability were investigated as a function of time. In vitro release kinetics were performed in a system with two compartments separated by a cellulose membrane. Intensity and duration of analgesia were evaluated in rats by sciatic nerve blockade.
The greatest stability, slower release profile and improvement in the local anesthetic activity of BZC were obtained with the formulation using USP mineral oil as component.
Results from our study provide useful perspectives on selection of the primary materials needed to produce suspensions of polymeric nanocapsules able to act as carriers of BZC, with potential future application in the treatment of pain.
本工作旨在研究油核组成对载苯佐卡因聚（丙交酯-乙交酯）纳米囊的理化性质和麻醉活性的影响。
用三种不同的油核组成制备含苯佐卡因的纳米囊，并考察其粒径、多分散性、Zeta 电位、pH 值和稳定性随时间的变化。体外释放动力学在由纤维素膜分隔的两个隔室系统中进行。通过坐骨神经阻滞评估大鼠的镇痛强度和持续时间。
用 USP 矿物油作为成分的制剂具有最大的稳定性、较慢的释放曲线和改善的局部麻醉活性。
本研究结果为选择生产能够作为 BZC 载体的聚合物纳米囊混悬液所需的主要材料提供了有用的视角，具有治疗疼痛的潜在未来应用。
