Bovine clinical mastitis has significant repercussions for farmers across the globe. Meloxicam, a COX-2 inhibitor, attenuates mastitis symptoms and is also approved for veterinary use. An RP-HPLC (Reverse Phase-High Performance Liquid Chromatography) method development and validation is essential in the pharmaceutical industry to assess API (Active Pharmaceutical Ingredient) quantity present in the pharmaceutical dosage forms. RP-HPLC method of meloxicam was developed and optimized with the aid of QbD (Quality by Design) using Box-Behnken design (BBD). The pH of the aqueous mobile phase, acetonitrile (ACN) percentage, and column temperature were chosen as influence variables, and retention time (RT) and tailing factor (Tf) were selected as response variables. The optimum experimental conditions were selected as pH ~ 3 of the aqueous mobile phase, 65% v/v ACN, and 30˚C as column temperature. The drug was eluted at 6.02 min RT with 1.18 as Tf. The method was subjected to validation for accuracy, linearity, precision, range, sensitivity, and robustness and was found to comply with ICH Q2 (R1) guidelines. The in vitro bioequivalent studies were performed in hydrochloric acid, pH ~ 1.2; acetate buffer, pH ~ 4.5; and phosphate buffer, pH ~ 6.8 for two veterinary brands of meloxicam tablets, and their release profiles were compared by mathematical models. Both the brands, brand 1 and 2 exhibited significant (Unpaired t-test, P < 0.05) differences in dissolution efficiency (DE) and mean dissolution time (MDT) except DE at pH 1.2. However, brands 1 and 2 showed similarity (f2 > 50) in terms of release of meloxicam except at pH 6.8 (f2 = 47.01). The in vitro release of meloxicam followed Peppas kinetics except for brand 2 at pH 6.8, where it followed the Higuchi model. Moreover, the recovery of meloxicam extracted with ACN in the milk sample was estimated to be 99.67 ± 0.58% significantly (Unpaired t-test, P < 0.05) higher than 90.34 ± 6.77% extracted with methanol. In conclusion, the optimized and validated RP-HPLC method of meloxicam may further be used for the analysis of drug content in pharmaceutical dosage forms in addition to biological fluids.

中文翻译：

---

计算质量设计策略，用于验证高效液相色谱方法，用于估计散装剂型和牛奶样品中的美洛昔康。

牛临床乳腺炎对全球农民产生了重大影响。美洛昔康是一种 COX-2 抑制剂，可减轻乳腺炎症状，也被批准用于兽医用途。RP-HPLC（反相高效液相色谱）方法的开发和验证对于制药行业评估药物剂型中 API（活性药物成分）的数量至关重要。使用 Box-Behnken 设计 (BBD) 借助 QbD（质量源于设计）开发并优化了美洛昔康的 RP-HPLC 方法。选择水性流动相的 pH 值、乙腈 (ACN) 百分比和柱温作为影响变量，并选择保留时间 (RT) 和拖尾因子 (Tf) 作为响应变量。最佳实验条件选择为水流动相pH~3、65% v/v ACN、柱温30℃。药物在 RT 6.02 分钟时洗脱，Tf 为 1.18。该方法经过准确性、线性、精密度、范围、灵敏度和稳健性验证，结果符合 ICH Q2 (R1) 指南。体外生物等效性研究在盐酸中进行，pH ~ 1.2；醋酸盐缓冲液，pH ~ 4.5；和磷酸盐缓冲液，pH ~ 6.8，用于两个兽用品牌的美洛昔康片，并通过数学模型比较它们的释放曲线。两个品牌（品牌 1 和 2）在溶出效率 (DE) 和平均溶出时间 (MDT) 方面均表现出显着差异（非配对 t 检验，P < 0.05），DE 除外，pH 为 1.2。然而，品牌 1 和品牌 2 在美洛昔康释放方面表现出相似性 (f2 > 50)，但 pH 6.8 时除外 (f2 = 47.01)。美洛昔康的体外释放遵循 Peppas 动力学，但品牌 2 在 pH 6.8 时遵循 Higuchi 模型。此外，牛奶样品中用乙腈提取的美洛昔康的回收率为 99.67 ± 0.58%，显着高于用甲醇提取的 90.34 ± 6.77%（未配对 t 检验，P < 0.05）。总之，经过优化和验证的美洛昔康 RP-HPLC 方法可进一步用于除生物液体外的药物剂型中的药物含量分析。