神经细胞中五种常见物质的太赫兹波谱的推定

Estimation of five common substances in nerve cells by terahertz spectroscopy

利用太赫兹时域光谱技术(THz-TDS)对神经细胞中常见的5种物质(L-谷氨酸、γ-氨基丁酸、肌酸、盐酸多巴胺和肌醇)的纯品进行特征谱检测。实验结果显示,5种物质在太赫兹波段有明显且独特的吸收谱线,并且同一种物质不同浓度的吸收系数符合朗伯比尔定律。此外,利用CASTEP软件包对5种物质的光谱进行仿真,结果显示太赫兹波段光谱特征吸收峰的成因主要由分子基团的振动而引起。之后,对肌醇、L-谷氨酸、γ-氨基丁酸和肌酸的1:1:1:1混合物的谱线进行检测,结合最小二乘法等算法倒推,可以准确推断每一种物质的含量及比例。结果表明,当4种物质混合时,物质含量推断的准确率为94%以上,这一研究结果对于癌组织的早期检测有重大意义。

The spectra of five substances commonly in nerve cells including,L-glutamic acid,Gamma Amino Butyric Acid(GABA),creatine,dopamine hydrochloride and myo-inositol are investigated by Terahertz Time-Domain Spectroscopy(THz-TDS).The experimental results show that the five substances have obvious and unique absorption spectra in terahertz region.For the same material,absorbance coefficient of different concentrations agrees with Lambert-Beer Law.In addition,the spectra of five substances are simulated by using CASTEP software package.The results show that the absorption peaks of terahertz spectrum are mainly due to the vibration of molecular groups.Furthermore,the spectra of 1:1:1:1 mixture of GABA,creatine,L-glutamic acid,myo-inositol are tested.By using the Least Square Method(LSM),the proportion and percentage of each substance are deduced exactly.The results show that the accuracy of substance content prediction is more than 94%when the four substances are mixed,which is of great significance for the early detection of cancer tissue.