Rapid Quantitative Analysis Of Teicoplanin Based On Near-infrared Spectroscopy Combined With Chemometrics

Teicoplanin(TCP) is an important lipoglycopeptide antibiotic produced by fermenting Actinoplanes teichomyceticus. In the fermentation process or pharmacokinetic analysis of teicoplanin, it is necessary to build a rapid(or online) method to detect the contents of related substance. Currently, the existing available methods for assaying TCP involve a tedious variety of reagents or lengthy run times, which are unsuitable for rapid measurement of TCP. In this study, a rapid quantitative analysis method for reagent-free determination for TCP aqueous solution and TCP–Tris–HCl mixture samples was developed with near-infrared(NIR) spectroscopy combined with chemometrics. In order to confirm the feasibility of quantitative analysis of TCP in mixture system with NIR spectroscopy, the latter were prepared to simulate TCP fermentation broth.In consideration of the absorption saturation of liquid samples, absorbance upper optimization partial least squares(AUO-PLS) method was first proposed to eliminate the noise disturbance with high absorption. It was further incorporated into the equidistant combination partial least squares(EC-PLS), which was proposed by our team and a new chemometrics method namely AUO-EC-PLS method was integrated. This method can eliminate noise and extract information, and obtain highly accurate analytical model.Through experiments and comparative analysis of the system, the following results were obtained. For TCP aqueous solution, the simplest model for TCP were proposed and the corresponding initial wavelength(I), number of wavelengths(N), number of wavelength gaps(G), number of PLS factors(F) were 1560 nm, 15, 10 and 8. The root-mean-square errors for prediction(SEP), correlation coefficient for prediction(RP) and relative SEP(RSEP) were 0.084 mg mL-1, 0.9990 and 2.4%. For TCP–Tris–HCl mixture samples, the parameter combinations(I, N, G, F) of the simplest model for TCP were 1520 nm, 28, 5 and 8. The corresponding SEP, RP and RSEP were 0.043 mg m L-1, 0.9998 and 1.0%. The parameter combinations(I, N, G, F) of the simplest model for Tris were 1084 nm, 13, 6 and 8. The corresponding SEP, RP and RSEP were 0.222 mg mL-1, 0.9989 and 1.6%.The result indicated that the predicted and actual concentrations had a high correlation, and the predicted error was insignificant. Thus it confirmed that the feasibility of reagent-free quantitative analysis of TCP with NIR spectroscopy. This study provided a valuable reference for further application of the proposed methods to TCP fermentation broth and to TCP pharmacokinetic analysis. Compared with other assay method, NIR spectroscopic analysis is a rapid, reagentless and highly accurate prediction technique and has wide application prospects.