In this work, the nano-g-C₃N₄/UiO-66-NH₂ composite was prepared by one-step solvothermal method. The as-prepared composite was characterized by scanning electron microscopy, Brunner-Emmet-Teller measurement, energy dispersive spectrometer, X-ray diffraction, and Fourier transform infrared spectroscopy. By using nano-g-C₃N₄/UiO-66-NH₂ composite as sorbent, a dispersive solid-phase extraction coupled with high-performance liquid chromatography was developed to sensitive analysis of food colorants including tartrazine, amaranth, carmine, sunset yellow, allura red and bright blue. The experiment parameters including the amount of sorbent, adsorption time, the pH of adsorption solution, desorption time, desorption solvent, the pH of desorption solution as well as the proportion between desorption solvent and buffer solvent were investigated. Under the optimized conditions, the limits of detection (S/N = 3) and limits of quantitation (S/N = 10) were determined in the ranges of 0.08–0.8 and 0.2–2.0 ng/mL, respectively. With the developed sample pretreatment method, carmine and brilliant blue were determined from blueberry juice by HPLC-DAD. The contents were calculated as 1.53 µg/mL and 0.17 µg/mL, respectively.

本工作采用一步溶剂热法制备了纳米gC ₃ N ₄ /UiO-66-NH _{2复合材料。}所制备的复合材料通过扫描电子显微镜、Brunner-Emmet-Teller 测量、能量色散光谱仪、X 射线衍射和傅里叶变换红外光谱仪进行了表征。通过使用 nano-gC ₃ N ₄ /UiO-66-NH ₂作为吸附剂的复合材料，开发了一种分散固相萃取与高效液相色谱相结合的方法，用于对包括柠檬黄、苋菜、胭脂红、日落黄、诱惑红和亮蓝色在内的食品着色剂进行灵敏分析。考察了吸附剂用量、吸附时间、吸附溶液pH、解吸时间、解吸溶剂、解吸溶液pH以及解吸溶剂与缓冲溶剂的比例等实验参数。在优化条件下，检测限 (S/N = 3) 和定量限 (S/N = 10) 分别确定在 0.08–0.8 和 0.2–2.0 ng/mL 的范围内。采用所开发的样品前处理方法，采用高效液相色谱-DAD法对蓝莓汁中的胭脂红和亮蓝进行了测定。含量计算为 1。