pH Sensitive Hydrogels in Drug Delivery: Brief History, Properties, Swelling, and Release Mechanism, Material Selection and Applications

AbstractSmart nanomaterials with stimuli-responsive behavior are considered as promising platform for various drug delivery applications. Regarding their specific conditions, such as acidic pH, drug carriers to treatment of tumor microenvironment need some criteria to enhance drug delivery efficiency. In this study, for the first time, pH-sensitive BSA-stabilized graphene (BSG)/chitosan nanocomposites were synthesized through electrostatic interactions between the positively charged chitosan nanoparticles and negatively charged BSG and used for Doxorubicin (DOX) encapsulation as a general anticancer drug. Physicochemical characterization of the nanocomposites with different concentrations of BSG (0.5, 2, and 5wt%) showed effective decoration of chitosan nanoparticles on BSG. Comparing DOX release behavior from the nanocomposites and free BSG-chitosan nanoparticles were evaluated at two pHs of 7.4 and 4.5 in 28 days. It was shown that the presence of BSG significantly reduced the burst release observed in chitosan nanoparticles. The nanocomposite of 2wt% BSG was selected as the optimal nanocomposite with a release of 84% in 28 days and with the most uniform release in 24 h. Furthermore, the fitting of release data with four models including zero-order, first-order, Higuchi, and Korsmeyer-Peppas indicated that the addition of BSG changed the release mechanism of the drug, enabling uniform release for the optimal nanocomposite in first 24 h, compared to that for pure chitosan nanoparticles. This behavior was proved using metabolic activity assay of the SKBR-3 breast cancer cell spheroids exposed to DOX release supernatant at different time intervals. It was also demonstrated that DOX released from the nanocomposite had a significant effect on the suppression of cancer cell proliferation at acidic pH.

Download Full-text

Chitosan-based Polymer Matrix for Pharmaceutical Excipients and Drug Delivery

Current Medicinal Chemistry ◽

10.2174/0929867325666180927100817 ◽

2019 ◽

Vol 26 (14) ◽

pp. 2502-2513 ◽

Cited By ~ 9

Author(s):

Md. Iqbal Hassan Khan ◽

Xingye An ◽

Lei Dai ◽

Hailong Li ◽

Avik Khan ◽

...

Keyword(s):

Drug Delivery ◽

Drug Delivery Systems ◽

Drug Carrier ◽

Drug Loading ◽

Delivery Systems ◽

Cancer Drug ◽

Release Mechanism ◽

Innovative Drug ◽

Pharmaceutical Excipients ◽

Weight Variation

The development of innovative drug delivery systems, versatile to different drug characteristics with better effectiveness and safety, has always been in high demand. Chitosan, an aminopolysaccharide, derived from natural chitin biomass, has received much attention as one of the emerging pharmaceutical excipients and drug delivery entities. Chitosan and its derivatives can be used for direct compression tablets, as disintegrant for controlled release or for improving dissolution. Chitosan has been reported for use in drug delivery system to produce drugs with enhanced muco-adhesiveness, permeation, absorption and bioavailability. Due to filmogenic and ionic properties of chitosan and its derivative(s), drug release mechanism using microsphere technology in hydrogel formulation is particularly relevant to pharmaceutical product development. This review highlights the suitability and future of chitosan in drug delivery with special attention to drug loading and release from chitosan based hydrogels. Extensive studies on the favorable non-toxicity, biocompatibility, biodegradability, solubility and molecular weight variation have made this polymer an attractive candidate for developing novel drug delivery systems including various advanced therapeutic applications such as gene delivery, DNA based drugs, organ specific drug carrier, cancer drug carrier, etc.

Download Full-text