Bacterial cellulose (BC) stands out as a promising candidate for novel drug delivery systems due to its micro-mesoporous nanofibrous interconnected structure. However, its performance is limited by the burst release of hydrophilic drugs and lower incorporation of the less water-soluble or insoluble drugs. In this study, we explored its potential as a drug carrier for two distinct types of drugs: Diclofenac sodium and Simvastatin, representing water-soluble and water insoluble compounds, respectively. To tune the morphology and drug-BC interaction, agar and chitosan were introduced into the culture medium during BC synthesis for in-situ modification. These modulated BCs are characterized and further analyzed through drug release studies and mathematical modeling to understand the mechanisms and key factors controlling the drug release behavior. Incorporating agar and chitosan into the BC network results in changes to its microstructure and crystallinity, which in turn affects the overall swelling, drug loading and release properties. Our results revealed that the BC followed a first-order quasi-Fickian kinetics for water-soluble drug and non-Fickian release mechanism for water-insoluble drug. In contrast, agar-modulated BC (A-MBC) demonstrated a non-Fickian first-order diffusion kinetics, with slow release for water-soluble drug and sustained release for the water-insoluble drug due to the higher density which impedes drug release. Chitosan-modulated BC (C-MBC) exhibited non-Fickian first-order kinetics, with slower release for water soluble drug. Further, C-MBC exhibited extended release for water insoluble drug to over 14 days, following first-order kinetics for the first 12 h, then transitioning to zero-order kinetics with a Case II release mechanism, attributed to drug-matrix interactions. These findings successfully demonstrate the possibility to tailor BC thus the release kinetics for both water-soluble and less soluble or insoluble drugs.
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