Study on Preparation and Analysis of Tea Polyphenols Loaded Gelatin/Chitosan Microspheres

In this study, chitosan and gelatin were used as shell materials of drug-loaded microspheres due to their good biocompatibility and degradability, tea polyphenols (TPPs) as core materials for their antibacterial and antioxidative properties. Gelatin/Chitosan (GE/CS) microspheres with different TPPs concentrations (4.975,6.622,8.264mg.g(-1)) were prepared by emulsion chemical-crosslinking method. Their morphology, physical and chemical properties were evaluated by SEM, Laser Particle Size Analyzer, FTIR spectrometry, in vitro release test, respectively. The results showed that the drug loading capacity enhanced with the increase of the TPPs concentration. The microspheres were mostly complete spheres with an average particle size of 682.2nm, which has only a small proportion of fragments and aggregation for high drug concentration. Gelatin and TPPs have a strong hydrophobic reaction, which resulted in higher drug encapsulation efficiency (89.25%, 92.26% and 82.38%). The in vitro release behaviors of microspheres at different concentrations all exhibited a biophasic characteristic, burst release occurred within the first 6 hours. The release percentages at this age for three concentrations of TPPs are 14.55%, 26.66%, 18.36% respectively; the subsequent steady release lasted for 210 hours.