Short and medium-chain fatty acids (SMCFAs) are known as essential metabolites found in gut microbiota that function as modulators in the development and progression of many inflammatory conditions as well as in the regulation of cell metabolism. Currently, there are few simple and low-cost analytical methods available for the determination of SMCFA. This report focuses on SMCFA analysis utilizing CE with indirect photometric detection (CE-IPD). A ribonucleotide electrolyte, 5’-adenosine mono-phosphate (5’-AMP), is investigated as an IPD reagent due to its high molar absorptivity and dynamic reserve compatible with separation and detection of SMCFA. The operating parameters like the composition of organic solvent, millimolar concentrations of the complexing agent (alpha-cyclodextrin), 5’-AMP and non-absorbing electrolyte (boric acid), as well as the applied voltage, are optimized for resolution, efficiency, and signal-to-noise ratio. A baseline resolution of all nine SMCFAs is achieved in less than 15 min. Additionally, the developed CE-IPD method shows promising potential to identifying SMCFA in rat fecal supernatant. The presented analytical assay is simple, economical, and has considerably good repeatability. The intraday and interday RSD of less than 1 and 2% for relative migration time, as well as less than 14 and 15% for peak area, respectively, were obtained for SMCFA in fecal solution.

中文翻译：

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使用间接光度检测的毛细管电泳分离短链和中链脂肪酸：第一部分：大鼠粪便中脂肪酸的鉴定

短链和中链脂肪酸 (SMCFA) 被称为肠道微生物群中发现的必需代谢物，在许多炎症状况的发展和进展以及细胞代谢的调节中起调节剂的作用。目前，可用于测定 SMCFA 的简单且低成本的分析方法很少。本报告的重点是利用带有间接光度检测 (CE-IPD) 的 CE 进行 SMCFA 分析。核糖核苷酸电解质 5'-单磷酸腺苷 (5'-AMP) 因其高摩尔吸收率和与 SMCFA 的分离和检测兼容的动态储备而作为 IPD 试剂进行了研究。操作参数，如有机溶剂的组成、络合剂（α-环糊精）、5'-AMP 和非吸收性电解质（硼酸）的毫摩尔浓度，以及施加的电压，都针对分辨率、效率和信噪比进行了优化。所有九个 SMCFA 的基线分辨率都在 15 分钟内实现。此外，开发的 CE-IPD 方法显示出在大鼠粪便上清液中鉴定 SMCFA 的潜力。所提出的分析方法简单、经济，并且具有相当好的重复性。对于粪便溶液中的 SMCFA，相对迁移时间的日内和日间 RSD 分别小于 1% 和 2%，峰面积分别小于 14% 和 15%。所提出的分析方法简单、经济，并且具有相当好的重复性。对于粪便溶液中的 SMCFA，相对迁移时间的日内和日间 RSD 分别小于 1% 和 2%，峰面积分别小于 14% 和 15%。所提出的分析方法简单、经济，并且具有相当好的重复性。对于粪便溶液中的 SMCFA，相对迁移时间的日内和日间 RSD 分别小于 1% 和 2%，峰面积分别小于 14% 和 15%。