利用太赫兹时域光谱技术研究了松材线虫、拟松材线虫、鲱鱼、鲑鱼和白杨等不同 DNA分子的吸收光谱,分析发现:随着样品厚度的减少,吸收峰会发生简并现象;折射率也会随着样品厚的增加而增加。通过比较不同 DNA分子的吸收谱还发现:相似物种 DNA分子比不同物种具有更多重合的吸收峰,推测这跟 DNA分子内碱基排序有关。在 DNA检测方面,傅里叶红外光谱仪和太赫兹光谱仪配合使用,可以从光谱的宽度和精度上互补,发挥更大优势。最后得到几种不同 DNA分子所有吸收峰位置,这为今后建立 DNA太赫兹光谱数据库和鉴别 DNA大分子奠定基础。

In this paper, the transmission spectral characteristics of Bx-DNA, Bm-DNA, herring-DNA, salmon-DNA and aspen-DNA have been studied by terahertz-time domain spectroscopy (THz-TDS) in the frequency range of 0.5-2.5THz. The absorption peaks have the phenomenon of merger when the thickness of the samples decrease, and the refractive index increases as the thickness of the samples increasing. By comparing with the absorption coefficient of different kinds of DNA molecules, we have found that the homologous species have more same absorption peaks than different species. In the detection of DNA, use of Fourier infrared spectrometer and terahertz spectrometer can obtain the accuracy and width of the spectra simultaneously. We also have picked up different DNA samples of which absorption peaks are in the frequency range of 0.5-2.5 THz in the experiments and we want to establish the database of DNA terahertz spectroscopy and identify the DNA macromolecules.