Extraction, characterization and evaluation of natural chitosan from Penaeus monodon for the formulation of domperidone microspheres

Background: This research work was aimed at extracting and characterizing chitosan obtained from shells of Penaeus monodon for preparation of domperidone sustained release microspheres.

Methods: Extraction took three consecutive steps: deproteination, demineralization and deacetylation. Structure of chitosan, degree of crystallinity, functional groups in chitosan were done through scanning electron microscope, diffractometer, and infrared spectrophotometry respectively. X-ray fluorescence was used to show qualitative and quantitative elemental contents. Degree of deacetylation was carried out using potentiometric titration. Microspheres were prepared by external gelation technique using tripolyphosphate as cross-linking agent and characterized for drug entrapment efficiency and drug release profile. Domperidone release data were analysed according to zero-order kinetics, first order kinetics and Higuchi model.

Results: FTIR spectrum of chitosan contained 12 major peaks between 861.0 and 3276.3 cm-1; Particle size and shape were even at low magnification and a rougher particle surface with increased magnification. XRD showed strong reflections at 2? angles of 15.2°, 16.0°, 17.2°, 23.5°, 38.2° and 50.8. X-ray fluorescence showed heavy presence of calcium having a 14 % of the constituents. Domperidone microspheres loaded chitosan showed the particle size ranging from 50 µm to 179 µm. Degree of deacetylation was 65.2 %. Drug entrapment efficiency was in the range of 39.0 - 78.4 % and about 71.0 % of the drug was released in 41/2 hr. Batches 1-11 followed zero order, via Fickian diffusion.

Conclusion: Chitosan obtained from Penaeus monodon could be used in the formulation of domperidone microspheres with varying natural polymer concentrations.