School of Pharmacy, Southwest Medical University, Luzhou, Sichuan, 646000, China.
School of Pharmacy, Southwest Medical University, Luzhou, Sichuan, 646000, China; Sichuan college of traditional Chinese medicine, Mianyang, Sichuan, China.
Anal Chim Acta. 2022 Sep 22;1227:340329. doi: 10.1016/j.aca.2022.340329. Epub 2022 Aug 29.
Considering the highly carcinogenic and mutagenic of anionic azo dyes to the environment and humans, the development of high efficiency adsorbent for them are of great significance. In this study, a novel hydroxyl-riched covalent organic framework (denoted as COF-OH), which can act as an advance adsorbent for anionic azo dyes, was fabricated for the first time. The as-prepared COF-OH demonstrated good dispersion in water, remarkable adsorption performances and good selectivity for anionic azo dyes including eriochrome black T, eriochrome blue black R and congo red. The adsorption capacities of them ranged from 90.71 to 229.12 mg g, and the extraction efficiencies of them (>75.91%) were much higher than other dyes (e.g. Methylene blue, direct red 80, 1.46%-39.57%). By optimizing the adsorption conditions (adsorbent dosage, adsorption time, pH, and salt concentration) and desorption conditions (desorption solvent, desorption time and desorption frequency), a dispersive micro solid-phase extraction (D-μ-SPE) method was developed. Further, coupled D-μ-SPE with HPLC-PDA analysis, an effective method was fabricated for the extraction and detection of three selected dyes. The method showed good linearity in the range of 0.1-200 μg mL (R > 0.9966), low limits of quantification (0.10 μg mL-2.00 μg mL), low limits of detection (0.03-1.50 μg mL) and good precision. Finally, the COF-OH based D-μ-SPE was successfully applied to extract three selected dyes from water samples (recoveries ranged from 73.90 to 104.00%) and congo red from beverages (recoveries ranged from 81.40 to 111.80%). Besides, by using computer simulation, FT-IR and UV-vis analysis, the adsorption mechanisms of COF-OH to three selected dyes were explored preliminarily.
考虑到阴离子偶氮染料对环境和人类具有高度的致癌性和致突变性，因此开发高效的吸附剂对于它们具有重要意义。本研究首次制备了一种新型富含羟基的共价有机骨架（记为 COF-OH），它可以作为阴离子偶氮染料的先进吸附剂。所制备的 COF-OH 在水中具有良好的分散性，对包括铬黑 T、铬蓝黑 R 和刚果红在内的阴离子偶氮染料表现出良好的吸附性能和良好的选择性。它们的吸附容量范围为 90.71-229.12 mg g，萃取效率（>75.91%）远高于其他染料（如亚甲蓝、直接红 80、1.46%-39.57%）。通过优化吸附条件（吸附剂用量、吸附时间、pH 值和盐浓度）和洗脱条件（洗脱溶剂、洗脱时间和洗脱频率），开发了一种分散固相微萃取（D-μ-SPE）方法。进一步将 D-μ-SPE 与 HPLC-PDA 分析相结合，建立了一种用于三种选定染料提取和检测的有效方法。该方法在 0.1-200 μg mL-1 范围内具有良好的线性关系（R>0.9966），低定量限（0.10 μg mL-2.00 μg mL-1），低检测限（0.03-1.50 μg mL-1）和良好的精密度。最后，COF-OH 基 D-μ-SPE 成功地从水样中提取三种选定的染料（回收率为 73.90%-104.00%）和饮料中的刚果红（回收率为 81.40%-111.80%）。此外，通过计算机模拟、FT-IR 和 UV-vis 分析，初步探讨了 COF-OH 对三种选定染料的吸附机理。
