注射是将药物直接递送至关节胶囊的一种方式。利用这种可能性,局部麻醉药,如布比卡因(Bu),可以以悬浮液的形式施用。这项工作的目的是提出一种基于甲基纤维素的水凝胶掺入布比卡因用于关节内注射,并研究药物从水凝胶到不同受体介质的释放动力学,反映健康关节的滑液和发炎关节的滑液。使用流动装置进行药物释放研究。药物被释放到四种不同的受体流体:磷酸盐缓冲液pH=7.4(PBS7.4),磷酸盐缓冲液pH=6.8(PBS6.8),磷酸盐缓冲液pH=7.4与高分子量透明质酸钠(PBS7.4H),和磷酸盐缓冲液pH=6.8与低分子量透明质酸钠(PBS6.8L)。在37°C的温度下进行研究。Bu释放的吸光度在262nm的波长下每2分钟测量24小时。Bu对受体介质PBS7.4,PBS6.8,PBS7.4H,用一级动力学和二级方程最好地描述了PBS6.8L。根据这些模型,当Bu释放到PBS7.4流体中时,释放速率常数最高,分别为k1=(7.20±0.01)×10-5min-1和k2=(3.00±0.04)×10-6mg-1×min-1。受体介质的相对粘度,pH值,在受体液中加入高分子量或低分子量透明质酸钠(HAH或HAL)影响药物的溶出。Bu释放到反映健康滑液的介质中与其释放到发炎关节的流体中的模式不同。
Injections are one way of delivering drugs directly to the joint capsule. Employing this possibility, local anesthetic, such as bupivacaine (Bu), in the form of the suspension can be administered. The aim of this work was to propose a methylcellulose-based hydrogel-incorporated bupivacaine for intra-articular injections and to study the release kinetics of the drug from the hydrogel to different acceptor media, reflecting the synovial fluid of a healthy joint and the synovial fluid of an inflamed joint. The drug
release studies were performed employing the flow apparatus. The drug was released to four different acceptor fluids: phosphate buffer pH = 7.4 (PBS7.4), phosphate buffer pH = 6.8 (PBS6.8), phosphate buffer pH = 7.4 with the high-molecular-weight sodium hyaluronate (PBS7.4H), and phosphate buffer pH = 6.8 with the low-molecular-weight sodium hyaluronate (PBS6.8L). The investigation was carried out at the temperature of 37 °C. The absorbance of the Bu released was measured at the wavelength of 262 nm every 2 min for 24 h. The
release profiles of Bu to the acceptor media PBS7.4, PBS6.8, PBS7.4H, and PBS6.8L were described best by the first-order kinetics and the second-order equation. According to these models, the
release rate constants were the highest when Bu was released to the fluid PBS7.4 and were k1 = (7.20 ± 0.01) × 10-5 min-1 and k2 = (3.00 ± 0.04) × 10-6 mg-1 × min-1, respectively. The relative viscosity of the acceptor medium, its pH, and the addition of high-molecular-weight or low-molecular-weight sodium hyaluronate (HAH or HAL) to the acceptor fluid influenced the drug dissolution. The
release of Bu into the medium reflecting healthy synovial fluid takes a different pattern from its
release into the fluid of an inflamed joint.