Two-Dimensional Mid- and Near-Infrared Correlation Spectroscopy for Rhubarb Identification

Two-dimensional mid- and near-infrared correlation spectroscopy has been an attractive and rapidly developing spectral technique and has been applied in many fields. The purpose of the present paper is to demonstrate the potential of the 2D MIR-NIR correlation spectroscopy in investigating the differences between official and unofficial rhubarb samples. The characters of official and unofficial rhubarbs can be discriminated quickly and nondestructively by using this technique. The resolution of spectra can be enhanced and more information can be obtained by two-dimensional correlation spectroscopy. Some issues related with correlation bands and characteristic peaks in the measurement spectra and their relationship with medicinal functions of rhubarb are discussed. Results show that the two-dimensional correlation spectroscopy of mid-infrared and near-infrared spectra can be a useful tool for investigating the characteristic differences of official and unofficial rhubarb samples.