Background: Periodontitis is chronic bacterial induced infection capable of destroying tooth
supporting tissues leading to pain, inflammation and tooth loss.
Objective: The objective of the study was to optimize and evaluate Doxycycline Hyclate (DX) entrapped
crosslinked chitosan microspheres by employing quality by design (QbD) for the treatment of
Methods: Plackett-Burman Factorial Design was applied, and screening of significant factors was done
by Pareto, half-normal and main-effect plots. The optimized batch was evaluated for FTIR, XRD, SEM,
in-vitro drug release, swelling, and mucoadhesion. Cytocompatibility, antimicrobial, and stability studies
were performed to prove its safety, efficacy and long-term utility respectively.
Results: The responses like particle size, entrapment efficiency, and time for 80% of drug release was
optimized at 75.45 μm, 88.87 % and 10.41 days respectively. FTIR reaffirmed formation of crosslinked
microspheres. XRD plots indicated conversion of crystalline DX into amorphous form within microspheres.
SEM evidenced spherical microspheres with smooth surfaces. Optimized microspheres
showed slow and extended release for about fourteen days. Moreover, chitosan-vanillin (CSV) microspheres
exhibited slow swelling with high mucoadhesion attributed to its high hydrophobicity and low
degree of crosslinking than chitosan-glutaraldehyde (CSG) microspheres. SRB assay demonstrated high
cytocompatibility of CSV than CSG microspheres against L929 cell lines. The optimized microspheres
maintained a significant zone of inhibition against Staphylococcus aureus and Escherichia coli growth
and showed prolonged stability for use.
Conclusion: CSV microspheres showed great potential for their utility in chronic infections such as
periodontitis by providing controlled and prolonged delivery of DX.