In this research, a new magnetic sorbent material composed of three-dimensional graphene aerogel decorated with Fe3O4 nanoparticles attached to hollow sporopollenin exine capsules was synthesized and applied for extraction of vitamin D3 before HPLC-UV analysis. The adsorbent was characterized by FT-IR, SEM, VSM, and zeta potential techniques. The important parameters of the extraction process, including adsorbent dosage, desorption conditions, adsorption time, pH, and salt concentration, were investigated. Under the optimized condition, the method analytical figures of merit were evaluated as follows: linear dynamic range, 10-500 μg L-1; limit of detection, 3.01 μg L-1; determination coefficient (R2), 0.9960; intra-day RSD, 5.28%; and inter-day RSD, 8.17%. The applicability of the method was assessed for the determination of vitamin D3 in different unfortified and fortified bovine milk samples, and the recoveries in the 71.8-113.3% range with the RSDs within 1.4-7.0% were obtained.

中文翻译：

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基于磁性三维石墨烯-孢粉蛋白吸附剂的分散微固相萃取法测定牛乳中的胆钙化固醇（维生素D3）。

在这项研究中，合成了一种新型的磁性吸附材料，该材料由三维石墨烯气凝胶组成，该气凝胶由附着在空心孢粉外膜胶囊上的Fe3O4纳米颗粒修饰而成，并用于HPLC-UV分析之前的维生素D3的提取。通过FT-IR，SEM，VSM和ζ电位技术对吸附剂进行了表征。研究了萃取过程中的重要参数，包括吸附剂量，脱附条件，吸附时间，pH和盐浓度。在最佳条件下，该方法的分析品质因数评估如下：线性动态范围，10-500μgL-1；检测限，3.01μgL-1; 测定系数（R2）为0.9960; 日内RSD为5.28％；日内RSD为8.17％。