Formulation development, characterization, and evaluation of sorafenib-loaded PLGA-chitosan nanoparticles

The basic purpose of this work was to develop environmentally friendly, biodegradable, and biocompatible polymeric nanoparticles of sorafenib that can effectively release the desired drug in a customized and controlled manner for targeting hepatocellular carcinoma. The solvent evaporation technique was employed for the synthesis of sorafenib-loaded PLGA-chitosan nanoparticles, followed by various experimental specifications and compatibility studies using poloxamer 407 as the stabilizer. The best nanoparticles thus synthesized were selected to be used for cytotoxicity investigations through in vitro and in vivo assessments. For the in vitro drug release tests, the dialysis bag diffusion technique was used. For both chitosan nanoparticles and PLGA loaded with sorafenib, a biphasic release pattern was found, exhibiting a protracted release lasting 10 days after a 24-h burst release. As experimental animals, rabbits were utilized to evaluate different in vivo pharmacokinetic properties of the selected formulations. Plasma samples were extracted with acetonitrile and analyzed through the developed HPLC method. Pharmacokinetic parameters such as AUC0-t, Cmax MRT, Vd, and half-life (t1/2) were enhanced significantly (p ≤ 0.001), while clearance was considerably decreased (p ≤ 0.001) for the chosen synthesized nanoparticles in contrast to the commercially accessible sorafenib formulation (Nexavar®). The cytotoxicity of the reference drug and sorafenib-loaded PLGA and chitosan nanoparticles was calculated by performing an MTT assay against HepG2 cell lines. The developed polymeric sorafenib nanoformulations possess the appropriate physicochemical properties, better targeting, surface morphology, and prolonged release kinetics. The pharmacokinetic parameters were improved significantly when the results were compared with commercially available sorafenib formulations.

Development and optimization of pH-responsive PLGA-chitosan nanoparticles for triggered release of antimicrobials

The aim of this work was to develop and optimize a pH-responsive nanoparticle based on poly(D,L-lactide-co-glycolide) (PLGA) and chitosan (CHIT) for delivery of natural antimicrobial using trans-cinnamaldehyde (TCIN) as a model compound. The optimization was performed using a central composite design and the desirability function approach. The optimized levels of variables considering all significant responses were 4% (w/w) of TCIN and 6.75% (w/w) of CHIT. After, optimized nanoparticles were produced and characterized according to their physicochemical properties and their antimicrobial activity against Salmonella Typhimurium and Staphylococcus aureus. Optimized nanoparticles characterization indicated a satisfactory TCIN encapsulation (33.20 ± 0.85%), spherical shape, pH-responsive controlled release, with faster release in the presence of CHIT at low pH, and enhanced antimicrobial activity against both pathogens. TCIN encapsulation using PLGA coated with CHIT enhanced its antimicrobial activity and generated a delivery system with pH-sensitivity for controlled release with promising properties for food safety applications.

Agarose-based biomaterials for tissue engineering

Agarose is a natural polysaccharide polymer having unique characteristics that give reason to consider it for tissue engineering applications. Special characteristics of agarose such as its excellent biocompatibility, thermo-reversible gelation behavior and physiochemical features support its use as a biomaterial for cell growth and/or controlled/localized drug delivery. The resemblance of this natural carbohydrate polymer to the extracellular matrix results in attractive features that bring about a strong interest in its usage in the field. The scope of this review is to summarize the extensive researches addressing agarose-based biomaterials in order to provide an in-depth understanding of its tissue engineering-related applications.

Chitosan-modified PLGA polymeric nanocarriers with better delivery potential for tamoxifen

Breast cancer is believed as the second most common cause of cancer-related deaths in women for which tamoxifen is frequently prescribed. Despite many promises, tamoxifen is associated with various challenges like low hydrophilicity, poor bioavailability and dose-dependent toxicity. Therefore, it was envisioned to develop tamoxifen- loaded chitosan-PLGA micelles for potential safe and better delivery of this promising agent. The chitosan-PLGA copolymer was synthesised and characterised by Fourier Transform-Infrared, Ultraviolet-visible and Nuclear Magnetic Resonance spectroscopic techniques. The drug-loaded nanocarrier was characterised for drug-pay load, micrometrics, surface charge and morphological attributes. The developed system was evaluated for in-vitro drug release, haemolytic profile, cellular-uptake, anticancer activity by cytotoxicity assay and dermatokinetic studies. The developed nano-system was able to substantially load the drug and control the drug release. The in-vitro cytotoxicity offered by the system was significantly enhanced vis-a-vis plain drug, and there was no substantial haemolysis. The IC₅₀ values were significantly decreased and the nanocarriers were uptaken by MCF-7 cells, noticeably. The carrier was able to locate the drug in the interiors of rat skin in considerable amounts to that of the conventional product. This approach is promising as it provides a biocompatible and effective option for better delivery of tamoxifen.