Development of UV spectrophotometry methods for concurrent quantification of amlodipine and celecoxib by manipulation of ratio spectra in pure and pharmaceutical formulation

Recently, the United States Food and Drug Administration approved a new oral dosage preparation of amlodipine besylate (AML) and celecoxib (CEL) for the management of hypertension and osteoarthritis. However, no simultaneous estimation procedures for these two analytes have been described. Hence, two simple, accurate, and precise ultraviolet spectroscopic procedures that manipulated the ratio spectra were established for concurrent quantification of AML and CEL using ethanol as a solvent. The first method involves determining the peak-to-trough amplitude difference of the ratio spectra of AML and CEL. The second method involves determining the peak amplitude of the ratio first derivative (Δλ 4 nm) spectra of AML and CEL at 334.2 nm and 254.2 nm, correspondingly. Both methods showed linearity in the range of 1–6 μg mL-1 for AML and 5–40 μg mL-1 for CEL with an excellent correlation coefficient (近日，美国食品药品监督管理局（United States Food and Drug Administration）批准了一款新型苯磺酸氨氯地平（amlodipine besylate, AML）与塞来昔布（celecoxib, CEL）口服制剂，用于高血压与骨关节炎的临床管理。然而，目前尚未有针对这两种分析物的同步定量检测方法被报道。因此，本研究建立了两种简便、准确且精密度优异的紫外分光光度法，以乙醇作为溶剂，通过比值光谱技术实现AML与CEL的同时定量分析。第一种方法通过测定AML与CEL比值光谱的峰谷振幅差完成定量；第二种方法则分别在334.2 nm与254.2 nm处，测定AML与CEL的比值一阶导数（Δλ=4 nm）光谱的峰振幅。两种方法的线性范围均为：AML 1~6 μg·mL⁻¹，CEL 5~40 μg·mL⁻¹，且相关系数优异（