Spray-dried chitinosans: Part I: preparation and characterization

Abstract

Purpose: Physicochemical and micromeritic characterization of chitinosans. Methods: Chitinosans subjected to N-deacetylation and depolymerization were characterized for degree of N-deacetylation (DD), molecular weight (MW), p K a, particle size determination and morphology, tap/bulk density measurements, surface area determinations, and determination of flow properties. Results: The chitinosan DDs and MWs were dependent on the processing conditions and ranged from 66 to 89% and 2–522 kDa, respectively. Chitinosan particle sizes and shapes were dependent on drying conditions (range 8–465 μm). Spray-dried chitinosans were spherical and had smaller particle sizes than the non-spray-dried materials which were irregularly shaped particles. Higher density values were obtained for processed materials than those for the raw material. Lower specific surface areas were observed for non-spray-dried chitinosans (0.28–1.59 m 2/g) than for spray-dried chitinosans (0.74–3.01 m 2/g). Weight variation of chitinosan tablets indicated that spray-dried chitinosans possessed improved flow characteristics as compared with tray-dried chitinosans. Conclusions: The effect of drying method employed in chitinosan manufacture, i.e. spray versus tray drying, on the physicochemical and micromeritic properties of the resultant chitinosans were evaluated. Although the drying methods did not significantly influence the physicochemical properties, they affected the micromeritic properties of the resultant chitinosans.