AbstractThe authors describe the preparation of copper-doped magnetic microspheres (Cu-Fe3O4) by a solvothermal method. Due to their good magnetic property and high affinity for compounds containing an imidazole moiety (containing N-H), they are excellent adsorbents for such compounds as tested by eighteen compounds. Specifically, a method has been developed for magnetic solid-phase extraction (MSPE) of theophylline (TP) from plasma. The method enables selective enrichment of TP over many potential interferents that can occur in plasma. Following elution with alkaline methanol, TP was quantified by HPLC-UV at a detection wavelength of 272 nm. Under the optimized conditions, a linear response is found for the 0.02 to 20 μg·mL−1 concentration range, and the limit of detection is as low as 3 ng·mL−1. Recoveries from spiked samples range from 91.2 to 100.4%, and the repeatabilities are between 2.9 and 12% (for n = 6). The method was successfully applied to the determination of TP in rabbit and rat plasma. Graphical abstractCopper-doped magnetic microspheres are described that show good magnetic property and high affinity for compounds containing an imidazole moiety (containing an N-H group). They were successfully applied to the selective extraction of theophylline in plasma.

中文翻译：

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在 HPLC 定量之前，通过掺杂铜的磁性微球从血浆中选择性提取茶碱

摘要 作者描述了通过溶剂热法制备铜掺杂磁性微球 (Cu-Fe3O4)。由于它们具有良好的磁性和对含有咪唑部分（含 NH）的化合物的高亲和力，它们是此类化合物的优良吸附剂，经 18 种化合物测试。具体而言，已经开发了一种用于从血浆中提取茶碱 (TP) 的磁性固相萃取 (MSPE) 方法。该方法能够选择性地富集 TP，而不是血浆中可能出现的许多潜在干扰物。用碱性甲醇洗脱后，通过 HPLC-UV 在 272 nm 检测波长下对 TP 进行定量。在优化条件下，在 0.02 至 20 μg·mL-1 浓度范围内发现线性响应，检测限低至 3 ng·mL-1。加标样品的回收率范围为 91。2 到 100.4%，重复性在 2.9 到 12% 之间（对于 n = 6）。该方法已成功应用于兔和大鼠血浆中TP的测定。图形摘要描述了掺杂铜的磁性微球，其对含有咪唑部分（含有 NH 基团）的化合物显示出良好的磁性和高亲和力。他们成功地应用于血浆中茶碱的选择性提取。