Design, optimization and characterizations of chitosan fortified calcium alginate microspheres for the controlled delivery of dual drugs

Periodontal disease is chronic, highly prevalent infectious disease that requires prolonged and controlled delivery of antimicrobial agents into pockets. To achieve this objective, dual antimicrobials encapsulated chitosan fortified calcium alginate (CS-Ca-SA) microspheres were formulated by application of Plackett-Burman factorial design. The microspheres were optimized for particle size (PS), entrapment efficiency (EE) and drug release. The optimized microspheres presented average PS of 74-461 µm and EE of 62.45-86.20% with controlled drug delivery for 120 hours. FTIR disclosed successful complexation between SA and CS. DSC and XRD studies showed changes in the crystallinity of drugs in microspheres. Shape factor and SEM demonstrated spherical to pear-shaped microspheres. Release exponent >0.43 and high diffusion coefficients revealed non-Fickian-based diffusion-limited drug release. CS-Ca-SA microspheres exhibited surface pH of 6.5 ± 0.5, moderate swelling, less erosion and improved mucoadhesion over Ca-SA microspheres. Also, significant antimicrobial activity against Escherichia coli and Staphylococcus aureus and cytocompatibility with L929 cell lines were observed. Further, microspheres exhibited long-term stability on refrigeration. The outcomes of study supported the potential of dual polymer and dual drug-based biodegradable, stable, non-toxic, mucoadhesive, controlled and prolonged drug release microspheres as more patient compliant by administration into periodontal pockets for the management of periodontal disease.