Construction of predictive models for gentamicin contents in aqueous solution using specific near infrared spectral regions

Component control is a key step of the quality control process in gentamicin (GM) production. The near infrared (NIR) method allows the rapid analysis of various components for the on-line control in the production process. In this study, we selected specific NIR spectral regions and eliminated solvent interference in constructing the predictive models of GM content in aqueous solution. We found that two factors could lead to better NIR predictions: (i) the combined use of specific NIR spectral regions related to both structural characteristics and content; and (ii) the analysis of sample spectra based on solvent reference spectra to identify and extract spectral information of testing components. We constructed predictive models for total GM C components, GM C1a (C1a), micronomicin (MCR) and sisomicin (SISO) in aqueous solution, respectively. These models can be used for the quick content analysis of different components in various types of GM injection samples.