Copper nanoparticles (CuNPs) were prepared through a wet chemistry method to be used as substituents for noble-metal-based materials in the determination of cephalosporin antibiotics in urine using surface-enhanced Raman spectroscopy (SERS). The synthesis of the CuNPs was optimized to maximize the analytical signal, and microwave heating was used to increase the reaction rate and improve the homogeneity of the CuNPs. Ceftriaxone (CTR), cefazolin (CZL), and cefoperazone (CPR) were used as the analytes of interest. The determination tests were performed on artificially spiked samples of real human urine with concentrations corresponding to therapeutic drug monitoring (TDM) (50-500 μg mL-1). Urine samples collected in the morning and during the day were used to account for deviations in the urine composition, and the universality of the proposed protocol was ensured by performing sample dilution as a pretreatment. The use of calibration plots in the form of Freundlich adsorption isotherms yielded linear calibration plots. All limits of detection were lower than the minimal concentrations required for TDM, equaling 7.5 (CTR), 8.8 (CZL), and 36 (CPR) μg mL-1. Comparison of CuNPs with Ag and Au nanoparticles (AgNPs and AuNPs, respectively) confirmed that CuNPs offered a competitively high Raman enhancement efficiency (for excitation at 638 nm). Further, although the CuNPs demonstrated poorer temporal stability as compared with the AgNPs and AuNPs, the use of freshly prepared CuNPs resulted in satisfactory accuracy (recovery = 93-107%). Given the short analysis time (<20 min, including the time for the synthesis of the CuNPs and the SERS measurements using a portable Raman spectrometer), low sensitivity to the presence of the primary intrinsic urine components and satisfactory figures of merit of the proposed protocol for the determination of cephalosporin antibiotics in urine, it should be suitable for use in TDM.

中文翻译：

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用于基于 SERS 测定加标人尿中某些头孢菌素抗生素的铜纳米颗粒

铜纳米粒子 (CuNPs) 通过湿化学方法制备，用作贵金属基材料的取代基，用于使用表面增强拉曼光谱 (SERS) 测定尿液中的头孢菌素抗生素。优化 CuNPs 的合成以最大化分析信号，并使用微波加热来提高反应速率并改善 CuNPs 的均匀性。头孢曲松 (CTR)、头孢唑啉 (CZL) 和头孢哌酮 (CPR) 用作目标分析物。测定测试是在人工加标的真实人类尿液样本上进行的，其浓度对应于治疗药物监测 (TDM) (50-500 μg mL-1)。早上和白天收集的尿液样本用于解释尿液成分的偏差，并且通过将样品稀释作为预处理来确保所提出方案的普遍性。Freundlich 吸附等温线形式的校准图的使用产生了线性校准图。所有检测限都低于 TDM 所需的最低浓度，等于 7.5 (CTR)、8.8 (CZL) 和 36 (CPR) μg mL-1。CuNPs 与 Ag 和 Au 纳米颗粒（分别为 AgNPs 和 AuNPs）的比较证实，CuNPs 提供了具有竞争力的高拉曼增强效率（用于 638 nm 激发）。此外，虽然与 AgNPs 和 AuNPs 相比，CuNPs 表现出较差的时间稳定性，但使用新鲜制备的 CuNPs 导致令人满意的准确性（回收率 = 93-107%）。鉴于分析时间短（<20 分钟，