Evaluation of the stability of Vitamin D3 encapsulated in chitosan-TPP using Raman microspectroscopy

Abstract

Vitamin D3 quantification is mainly performed via extraction and analysis in the High-Performance Liquid Chromatography (HPLC). Raman microspectroscopy is a promising technique to evaluate the stability of this active compound over time without any sample preparation. Thus, the objectives of this study will be: (i) to evaluate the potential of Raman microspectroscopy to distinguish and quantify vitamin D3 in chitosan/vitamin D3 matrices and, (ii) to evaluate the stability of this vitamin encapsulated in chitosan microparticles - sodium tripolyphosphate (TPP) by ionic gelation. First, suspensions of chitosan (2 mg.mL-1) with different vitamin D3 concentrations will be produced: 10, 25, 50, 100 and 200 mg.mL-1. Vitamin quantification will be performed by the conventional method (HPLC) and using the Raman. Spectra will be collected in the freeze-dried sample pellets. In order to construct a PLS (Partial Least Squares Classification) regression model, the spectral data will be analyzed by multivariate analysis using MATLAB and PLS Toolbox software. Next, microcapsules of vitamin D3, chitosan, and tripolyphosphate will be produced by ionic gelation. The suspensions will also be lyophilized and analyzed by HPLC and Raman every 7 days for 2 months. This study is part of the FAPESP process n. 2016 / 18788-1.