Determination of hainanmycin in the aqueous-alcohol solution by Fourier transform infrared spectroscopy

Fourier transform infrared(FT-IR) spectroscopy equipped with horizontal attenuated total reflection(ATR) accessory was applied to the multi-component quantitative analysis in organic phase, A novel method was developed to directly determine the Hainanmycin (HNMS, an insoluble antibiotic from the fermentation) in water and ethyl alcohol solution. Calibration models were established on the basis of partial least squares with infrared spectra (IR) and second-derivative absorbance spectra(DIR) of the standard mixtures. The better predicted results is obtained especially at lower concentration of HNMS by DIR method. The standard errors of prediction of HNMS by IR or DIR are 0.18 and 0.19 g/L, respectively, The standard errors of prediction of water and alcohol are 0.001 1 volume ratio by either quantitative method. The method is rapid and convenient without any pre-treatment.