拉西地平的太赫兹光谱实验研究

测量了高纯拉西地平(98%)和拉西地平口服药片(2%)0.5~1.8 THz的太赫兹反射时域信号，并分别提取出二者的吸收谱和折射率谱。通过将纯样品的吸收峰位与CASTEP晶体软件计算得到的吸收线位置进行比较，并用Lorentz线型函数对其中位置相近的吸收峰进行拟合，得到了拉西地平的指纹谱，并从实验上确定了拉西地平的六个特征频率，这些频率分别为0.62，0.78，1.07，1.28，1.63和1.76 THz；由于口服药片中添加了其他大分子物质作为辅料，这些物质带来的吸收本底会对拉西地平的特征峰的识别造成干扰，因此，特征吸收峰数量减少至四个，它们分别是0.62，0.78，1.28和1.63 THz；另外，纯样品和口服药片的折射率谱存在较大差异，这也与口服药中添加的辅料有关。尽管实际的拉西地平口服药片中含有的拉西地平的成分很低，但是，太赫兹指纹谱依然可以将拉西地平的特征频率识别出来。因此，太赫兹时域光谱技术对拉西地平药品的成分检测是十分有效的。

Experimental Study on Terahertz Spectrum of Lacidipine

The terahertz time-domain reflection signals of highly pure Lacidipine(98％)and Lacidipine tablets(2％)were measured and then their absorption and refractive index spectra were extracted respectively.Through comparing the frequencies between the measured absorption peaks and the results calculated by CASTEP software,we got the fingerprint of Lacidipine using Lorentz fitting.There were six characteristic frequencies located at 0.62,0.78,1.07,1.28,1.63 and 1.76 THz,respectively.Because other substances were added into tablets as supplementary materials,and the recognition of absorption characteristics of lacidipine was disturbed by absorption of these substances,the number of characteristic absorption peaks decreased to 4 at 0.62,0.78,1.28 and 1.63 THz.In addition,there was a large difference in the refractive index spectra of the pure samples and oral tablets,which was also related to the supplementary materials in the oral administration.Although Lacidipine's content was very low in the actual Lacidipine oral tablets,THz fingerprint spectrum could still recognize some characteristic frequencies.Therefore,the terahertz time-domain spectroscopy is an effective tool for detecting components of Lacidipine drugs.