Application of wavelet transform in improving resolution of two-dimensional infrared correlation spectroscopy

FTIR is a great improvement in IR spectroscopy, and two-dimensional infrared (21) IR) correlation spectroscopy well advances its capabilities. But for complicated mixture systems, such as traditional Chinese medicines, the spectra are rather similar and these methods fall short. To improve the resolution of 2D IR spectrum, and make it possible to distinguish complicated mixture systems, the application of wavelet transform to 2D IR was explored in this paper. After performing decomposition, processing, and reconstruction of the set of dynamic spectra, the resolution of the synchronous 2D IR correlation spectrum was improved obviously. More peaks appeared and the peaks became quite clear and separate. Four Coptis samples of aged 1-4 could be distinguished with this approach. Using wavelet transform, 2D IR would become more powerful in analysis and discrimination.