Studies on encapsulation of Rifampicin and its release from chitosan-dextran sulfate capsules

Optimally designed theranostic system based folic acids and chitosan as a promising mucoadhesive delivery system for encapsulating curcumin LbL nano-template against invasiveness of breast cancer

Curcumin is a potential candidate in cancer therapy due to its ability to inhibit many signalling pathways at the same time of exposure because of its unique content of aromatic ring, B diketone, olefinic linker, and O methoxy phenolic groups. Its applications in biomedical therapy is limited because of its sensitivity, and its rapid degradation. In the current study, curcumin inserted into polyelectrolyte pairs (protamine and dextran) and then was functionalized by folic acid conjugated chitosan used for the first time, as theranostic system. Such this strategy allows to improve its mucoadhesion and penetration that increases their accumulation inside cancer cells. CUR-LbL NPs were then used to investigate drug release inside Human Mammary Carcinoma (MCF-7 cell lines) after their incubations for 3 h, 6 h and 24 h. Flow cytometry indicated that the percentages of apoptosis, necrosis and cell cycle arrest were increased significantly in MCF-7 cell lines treated by CUR-LbL NPs. Furthermore, SEM image showed many debris in the section of MCF-7 treated by CUR-LbL NPs. Here, it can be summarized that curcumin functionalized by multi-layered polyelectrolyte capsules can be used as a model to study the fate of the adsorbed nanocarriers and to investigate the drug release inside cells.

Chitosan-based blends for biomedical applications

Polysaccharides are the most abundant naturally available carbohydrate polymers; composed of monosaccharide units covalently connected together. Chitosan is the most widely used polysaccharides because of its exceptional biocompatibility, mucoadhesion, and chemical versatility. However, it suffers from a few drawbacks, e.g. poor mechanical properties and antibacterial activity for biomedical applications. Blending chitosan with natural or synthetic polymers may not merely improve its physicochemical and mechanical properties, but may also improve its bioactivity-induced properties. This review paper summarizes progress in chitosan blends with biodegradable polymers and polysaccharides and their biomedical applications. Blends of chitosan with alginate, starch, cellulose, pectin and dextran and their applications were particularly addressed. The critical and challenging aspects as well as the future ahead of the use of chitosan-based blends were eventually enlightened.

Controlled Fabrication of Microparticles with Complex 3D Geometries by Tunable Interfacial Deformation of Confined Polymeric Fluids in 2D Micromolds

Polymeric microparticles with complex shapes have attracted substantial attention in many application areas because particle shape is a critical parameter to impart programmable functionalities. The formation of specific three-dimensional (3D) microstructures in a simple, scalable, and controllable manner is difficult. Here, we report the controlled fabrication of microparticles with complex 3D shapes based on the simple tuning of mold swelling and capillarity. Specifically, a photocurable solution loaded in micromolds is spatially deformed into complex shapes depending on the degree of molding swelling and capillarity, thereby producing polymeric microparticles with controlled 3D shapes upon photopolymerization. The results show that highly uniform microparticles with controlled two-dimensional (2D) and 3D shapes were fabricated from identical 2D micromolds via the simple tuning of the wetting fluids. This technique can be extended to produce highly complex microarchitectures with controlled 3D geometric domains via 2D mold designs. Finally, multicompartment microparticles with independently controlled 3D shapes for each compartment are produced by a simple combination of fabrication sequences. We envision that this strategy of producing 3D microarchitectures from easily designed simple micromolds could provide a path to new materials and new properties.