The combination of trimethoprim and sulfamethoxazole as a fixed-dose combination in the ratio 1:5 is known as cotrimoxazole. It is used as antibiotic to treat a variety of bacterial infections. Cotrimoxazole is part of the World Health Organization’s list of essential medicines. Cotrimoxazole is an example of a drug that was partially unavailable in Germany during the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) pandemic and the Ukraine war. The dependency on foreign sources of medicines is well known in Europe and resulted in the Pharmaceutical Strategy for Europe 2020, a strategy concept “will support the competitiveness and innovative capacity of the EU’s pharmaceutical industry”. High-performance thin-layer chromatography (HPTLC) is a cost-effective method for quantifying pharmaceutically active compounds. Diode-array detection (DAD) in conjunction with HPTLC can simultaneously detect ultraviolet‒visible (UV‒VIS) and fluorescence spectra directly from the plate. Visualization as a contour plot helps to identify the optimal wavelengths for compound quantification and reduce uncertainty in the determination. The quantification of trimethoprim and sulfamethoxazole is presented in a case study that highlights the key aspects for HPTLC quantification of pharmaceutical fixed-dose combinations with minimal uncertainty. HPTLC‒DAD allows quantification of trimethoprim and sulfamethoxazole with a required relative standard deviation of less than 2.5%.

甲氧苄啶和磺胺甲恶唑按 1:5 的比例组合而成的固定剂量组合称为复方新诺明。它被用作抗生素来治疗多种细菌感染。复方新诺明是世界卫生组织基本药物清单的一部分。复方新诺明就是在严重急性呼吸综合征冠状病毒 2 (SARS-CoV-2) 大流行和乌克兰战争期间在德国部分无法使用的药物的一个例子。对外国药品来源的依赖在欧洲是众所周知的，并催生了《2020年欧洲制药战略》，其战略概念是“将支持欧盟制药业的竞争力和创新能力”。高效薄层色谱 (HPTLC) 是一种经济高效的药物活性化合物定量方法。二极管阵列检测 (DAD) 与 HPTLC 相结合，可以直接从板上同时检测紫外可见 (UV-VIS) 和荧光光谱。可视化为等高线图有助于确定化合物定量的最佳波长并减少测定的不确定性。案例研究中介绍了甲氧苄啶和磺胺甲恶唑的定量，该案例研究强调了以最小不确定性对药物固定剂量组合进行 HPTLC 定量的关键方面。HPTLC-DAD 可以对甲氧苄啶和磺胺甲恶唑进行定量，所需的相对标准偏差小于 2.5%。