分别利用高效液相色谱法和太赫兹时域光谱技术对甲硝唑分析纯和口服甲硝唑溶液进行检测。以密度泛函理论的多种交换-关联函数模型为基础,计算甲硝唑在太赫兹波段的分子振动频率,并对甲硝唑的特征吸收峰进行了指认。实验结果显示:太赫兹光谱检测结果与高效液相色谱的实验结果具有良好的一致性,太赫兹时域光谱技术可以对药物残留进行快速检测。太赫兹时域光谱实验得到的甲硝唑特征吸收峰的位置与计算所得的理论值极为接近,这表明在系统可测范围内存在甲硝唑分子的振动频率,并且特征吸收频率的形成机制与分子基团的振动模式密切相关。这一研究对抗生素药品残留的快速检测以及化合物有效成分的鉴别具有重要的参考价值。

In this study, high-performance liquid chromatography and terahertz time-domain spectroscopy were used to experimentally detect metronidazole analytical pure and oral metronidazole. Based on various exchange-correlation function models of density functional theory, the molecular vibration frequencies of metronidazole in the terahertz band were calculated, and the characteristic absorption peaks of metronidazole were identified. The experimental results show that the results of terahertz time-domain spectroscopy are in good agreement with those of high-performance liquid chromatography, and terahertz time-domain spectroscopy can quickly detect drug residuals. The positions of the characteristic absorption peaks of metronidazole obtained via terahertz time-domain spectroscopy are very close to the calculated values, which indicates that the metronidazole molecular vibration frequency is in the measurable range of the system, and the formation mechanism of the characteristic absorption frequency is similar to the vibration mode of the molecular group. This research has important reference value for the applications of rapid detection of antibiotic drugs and the identification of active ingredients in compounds.