多孔芳香骨架吸附剂-固相萃取-高效液相色谱法同时测定辣椒粉中4种偶氮类染料

建立了固相萃取-高效液相色谱同时测定辣椒粉中对位红、酸性橙Ⅱ、苏丹红Ⅰ和苏丹红Ⅱ4种偶氮染料的方法。以多孔芳香骨架-6(PAF-6)材料作为固相萃取吸附剂,考察并获得了影响自制固相萃取柱的萃取效率和吸附容量等主要因素。在优化条件下,4种目标分析物的检出限(LOD)为1.5～7.0μg/L(信噪比S/N=3),定量限(LOQ)为5.0～22.1μg/L(S/N=10),加标回收率为76.5%～89.8%,相对标准偏差(RSD)均不大于5.3%(n=6)。此外,基于量子化学计算,考察了PAF-6与目标分析物之间的相互作用机制,结果表明,目标分析物可以稳定地吸附在PAF-6分子上。该方法准确可靠,具有良好的回收率和较高的灵敏度,可用于辣椒粉中4种偶氮类染料的检测。

Simultaneous determination of four azo dyes in paprika powder by high performance liquid chromatography using a porous aromatic framework as the solid-phase extraction sorbent

In this study, a solid-phase extraction-high performance liquid chromatography (SPE-HPLC) method was developed for the determination of Para Red, Orange Ⅱ sodium salt, Sudan Ⅰ, and Sudan Ⅱ in paprika powder based on a self-made porous aromatic framework-6 (PAF-6) solid-phase extraction cartridge. The major factors affecting the extraction efficiency and adsorption capacity of this solid-phase extraction were evaluated. Under optimized conditions, the limits of detection (LODs) and limits of quantification (LOQs) of the four target analytes ranged from 1.5 to 7.0 μg/L and 5.0 to 22.1 μg/L, respectively. The recoveries were in the range of 76.5-89.8%, and the relative standard deviation (RSD) was not more than 5.3% (n=6). Moreover, quantum chemistry calculations were performed to investigate the molecular interaction mechanism between the PAF-6 and target analytes. The results indicated that the target molecules could be stably adsorbed onto the PAF-6. The method is accurate, reliable, and sensitive, and can be successfully applied to detect the four azo dyes in paprika powder.