A modified C₁₈ column (Silpr‐2MI‐C18) was prepared using 2‐methylindole and C₁₈ reagent. The extent of C₁₈ hydrocarbon chain, conjugative rings and anion exchange site provided multiple retention mechanisms, including reversed‐phase liquid chromatography (RPLC), π–π interaction, hydrophilic interaction liquid chromatography (HILIC) and anion exchange chromatography (AEC). The separation of protected amino acids was investigated on the commercial C₁₈ and Silpr‐2MI‐C18 columns, while the chromatographic conditions, including methanol content and pH of the mobile phase, were studied. The separation arrangement of the hydrophilic amino acids was different on the Silpr‐2MI‐C18 column compared to the commercial C₁₈ column under RPLC mode. Furthermore, these amino acids were separated on the Silpr‐2MI‐C18 column under HILIC mode. The modified C₁₈ column was employed to separate amino acids, alkylbenzenes and polycyclic aromatic hydrocarbons under RPLC mode and inorganic anion under AEC mode. The results confirm that this new stationary phase of RPLC/HILIC/AEC has multiple interactions with different analytes. Effective retention of biological samples was found on the Silpr‐2MI‐C18 column by comparing the results obtained from the commercial C₁₈ column.

中文翻译：

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制备和评估带有C18和2-甲基吲哚的HPLC混合模式固定相

使用2-甲基吲哚和C ₁₈试剂制备了改进的C ₁₈色谱柱（Silpr-2MI-C18）。C ₁₈烃链，共轭环和阴离子交换位点的范围提供了多种保留机制，包括反相液相色谱（RPLC），π - π相互作用，亲水相互作用液相色谱（HILIC）和阴离子交换色谱（AEC）。在商业C ₁₈上研究了受保护氨基酸的分离和Silpr-2MI-C18色谱柱，同时研究了色谱条件，包括甲醇含量和流动相的pH值。在RPLC模式下，与商用C ₁₈色谱柱相比，Silpr-2MI-C18色谱柱上亲水性氨基酸的分离安排有所不同。此外，这些氨基酸在HILIC模式下在Silpr-2MI-C18色谱柱上分离。改装的C ₁₈色谱柱用于在RPLC模式下分离氨基酸，烷基苯和多环芳烃，在AEC模式下分离无机阴离子。结果证实，RPLC / HILIC / AEC的新固定相与不同分析物具有多种相互作用。通过比较从商业C ₁₈色谱柱获得的结果，可以在Silpr-2MI-C18色谱柱上找到有效保留生物样品的方法。