Capecitabine is a chemotherapeutic agent used for the treatment of patients with metastatic cancers. This study aimed at determining the drug capecitabine in a simple chemiluminescence (CL) system of acidic potassium permanganate using the stopped‐flow injection technique. Statistical methods were used to detect optimum conditions. The method showed two linear calibration ranges from 6.7 × 10⁻⁶ to 6.7 × 10⁻⁵ mol L⁻¹ and from 6.7 × 10⁻⁵ to 2.7 × 10⁻³ mol L⁻¹ with a detection limit of 1.5 × 10⁻⁶ mol L⁻¹. Chitosan‐modified magnetic nanoparticles were studied in the drug‐delivery experiments. According to the pH sensitivity of chitosan and low pH values in tumour cells, the chitosan‐coated magnetic nanoparticles could provide a good targeting drug‐delivery system to tumour sites. To evaluate the applicability of the method, the capecitabine‐loaded magnetic chitosan nanoparticles were synthesized with two different cross‐linkers; loading and releasing rates of the drug were investigated using the proposed CL method and an ultraviolet–visible light spectrophotometric method (absorption at 305 nm). The results showed a good correlation between the two methods, and it was found that the synthesized chitosan‐modified magnetic nanoparticles could be used for pH‐dependent release of capecitabine in cancer cells. Moreover, determination of capecitabine in tablets and synthetic samples was performed.

中文翻译：

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止流化学发光法测定抗癌药物卡培他滨：在药物分析和药物递送系统中的应用。

卡培他滨是用于治疗转移性癌症患者的化学治疗剂。这项研究旨在使用停流注射技术在酸性高锰酸钾的简单化学发光（CL）系统中确定卡培他滨药物。统计方法用于检测最佳条件。该方法显示了两个线性校准范围，分别为6.7×10 ^-6至6.7×10 ^-5 mol L ^-1和6.7×10 ^-5至2.7×10 ^-3 mol L ^-1，检出限为1.5×10 ^-6摩尔L ^-1。在药物递送实验中研究了壳聚糖修饰的磁性纳米颗粒。根据壳聚糖的pH敏感性和肿瘤细胞的低pH值，壳聚糖包被的磁性纳米粒子可以为肿瘤部位提供良好的靶向药物递送系统。为了评估该方法的适用性，使用两种不同的交联剂合成了卡培他滨负载的磁性壳聚糖纳米颗粒。使用提出的CL方法和紫外可见光分光光度法（在305 nm处吸收）研究了药物的负载和释放速率。结果表明两种方法之间具有良好的相关性，并且发现合成的壳聚糖修饰的磁性纳米颗粒可用于pH依赖的卡培他滨在癌细胞中的释放。此外，