Formulation and Evaluation of Glutaraldehyde-Crosslinked Chitosan Microparticles for the Delivery of Ibuprofen

Purpose: Toformulate glutaraldehyde-cross-linked chitosan-based microparticles and evaluate its suitability for the delivery of ibuprofen, a BCS class II drug.
Methods: Ibuprofen-loaded chitosan microparticles were prepared by emulsification-cross-linking technique using glutaraldehyde saturated toluene (GST) as the cross-linking agent. The microparticles were characterized with respect to morphology, particle size, microparticle yield and entrapment efficiency. The swelling behaviour of the particles and ibuprofen release were assessed in both simulated gastric fluid (SGF) without pepsin (pH 1.2) and simulated intestinal fluid (SIF) without pancreatin (pH 7.4).
Results: Discrete and free-flowing microparticles of size range 100.05 ± 8.82 to 326.70 ± 10.43 μm were obtained. The microparticles had a high yield (69.2 to 99.2 %) and exhibited greater water sorption capacity in SIF (122.2 %) than in SGF (60 %). Furthermore, the microparticles cross-linked with 10 ml of GST entrapped the highest amount of drug (23.32 ± 0.97 %) while those cross-linked with 25 ml GST had the highest yield of the microparticles (99.19 % ), and highest water sorption in SIF (122.2 %). Up to 93.6 % of the entrapped drug was released in SIF from microparticles cross-linked with 25 ml of GST. Drug release from microparticles cross-linked with 20 and 30 ml each of GST showed a biphasic pattern.
Conclusions: Entrapment of ibuprofen in glutaraldehyde-cross-linked chitosan microparticles can be exploited to target and control the release of the drug and possibly reduce its gastro-erosive side effects.

Keywords
Chitosan microparticles, Ibuprofen, Oral delivery, Gastrointestinal, Glutaraldehyde