Diabetic retinopathy (DR) is a condition that causes swelling of the blood vessels of the retina and leaks blood and fluids. It is the most severe form of diabetic eye disease. It causes vision loss in its advanced stage. Diabetic retinopathy is responsible for causing 26% of blindness. Very insufficient therapies are accessible for the treatment of DR. As compared to the conventional therapies, there should be enhanced research on the controlled release, shorter duration, and cost-effective therapy of diabetic retinopathy. The expansion of advanced nanocarriers-based drug delivery systems has been now employed to exploit as well as regulate the transport of many therapeutic agents to target sites via the increase in penetration or the extension of the duration of contact employing production by enclosing as well as distributing tiny molecules in nanostructured formulation. Various polymers have been utilized for the manufacturing of these nanostructured formulations. Chitosan possesses incredible biological and chemical properties, that have led to its extensive use in pharmaceutical and biomedical applications. Chitosan has been used in many studies because of its enhanced mucoadhesiveness and non-toxicity. Multiple studies have used chitosan as the best candidate for manufacturing nanocarriers and treating diabetic retinopathy. Numerous nanocarriers have been formulated by using chitosan such as nanostructured lipid carriers, solid lipid nanoparticles, liposomes, and dendrimers for treating diabetic retinopathy. This current review elaborates on the recent advancements of chitosan as a promising approach for the manufacturing of nanocarriers that can be used for treating diabetic retinopathy.
Recombinant adeno-associated virus (rAAV) has been developed as a safe and effective gene delivery vehicle to treat rare genetic diseases. This study aimed to establish a novel biomanufacturing process to achieve high production and purification of various AAV serotypes (AAV2, 5, DJ, DJ8). First, a robust suspensive production process was developed and optimized using Gibco Viral Production Cell 2.0 in 30-60 mL shaker flask cultures by evaluating host cells, cell density at the time of transfection and plasmid amount, adapted to 60-100 mL spinner flask production, and scaled up to 1.2-2.0-L stirred-tank bioreactor production at 37 °C, pH 7.0, 210 rpm and DO 40%. The optimal process generated AAV titer of 7.52-8.14 × 1010 vg/mL. Second, a new AAV purification using liquid chromatography was developed and optimized to reach recovery rate of 85-95% of all four serotypes. Post-purification desalting and concentration procedures were also investigated. Then the generated AAVs were evaluated in vitro using Western blotting, transmission electron microscope, confocal microscope and bioluminescence detection. Finally, the in vivo infection and functional gene expression of AAV were confirmed in tumor xenografted mouse model. In conclusion, this study reported a robust, scalable, and universal biomanufacturing platform of AAV production, clarification and purification.
Bone tissue engineering necessitates a stem cell source capable of osteoblast differentiation and mineralized matrix production. Dental pulp stem cells (DPSCs), a subtype of mesenchymal stem cells from human teeth, present such potential but face challenges in osteogenic differentiation. This research introduces an innovative approach to bolster DPSCs' osteogenic potential using niosomal and hyaluronan modified niosomal systems enriched with rosuvastatin. While rosuvastatin fosters bone formation by regulating bone morphogenetic proteins and osteoblasts, its solubility, permeability, and bioavailability constraints hinder its bone regeneration application. Using a Box-Behnken design, optimal formulation parameters were ascertained. Both niosomes were analyzed for size, polydispersity, zeta potential, and other parameters. They displayed average sizes under 275 nm and entrapment efficiencies exceeding 62%. Notably, niosomes boosted DPSCs' cell viability and osteogenic marker expression, suggesting enhanced differentiation and bone formation. Conclusively, the study underscores the potential of both niosomal systems in ameliorating DPSCs' osteogenic differentiation, offering a promising avenue for bone tissue engineering and regeneration.
Background: Polymeric nanoparticles can be used for wound closure and therapeutic compound delivery, among other biomedical applications. Although there are several nanoparticle obtention methods, it is crucial to know the adequate parameters to achieve better results. Therefore, the objective of this study was to optimize the parameters for the synthesis, purification, and freeze-drying of chitosan nanoparticles. We evaluated the conditions of agitation speed, anion addition time, solution pH, and chitosan and sodium tripolyphosphate concentration.
Results: Chitosan nanoparticles presented an average particle size of 172.8 ± 3.937 nm, PDI of 0.166 ± 0.008, and zeta potential of 25.00 ± 0.79 mV, at the concentration of 0.1% sodium tripolyphosphate and chitosan (pH 5.5), with a dripping time of 2 min at 500 rpm. The most representative factor during nanoparticle fabrication was the pH of the chitosan solution, generating significant changes in particle size and polydispersity index. The observed behavior is attributed to the possible excess of sodium tripolyphosphate during synthesis. We added the surfactants poloxamer 188 and polysorbate 80 to evaluate the stability improvement during purification (centrifugation or dialysis). These surfactants decreased coalescence between nanoparticles, especially during purification. The centrifugation increased the zeta potential to 40.8-56.2 mV values, while the dialyzed samples led to smaller particle sizes (152-184 nm). Finally, freeze-drying of the chitosan nanoparticles proceeded using two cryoprotectants, trehalose and sucrose. Both adequately protected the system during the process, and the sugar concentration depended on the purification process.
Conclusions: In Conclusion, we must consider each surfactant's benefits in formulations for selecting the most suitable. Also, it is necessary to do more studies with the molecule to load. At the same time, the use of sucrose and trehalose generates adequate protection against the freeze-drying process, even at a 5% w/v concentration. However, adjusting the percentage concentration by weight must be made to work with the CS-TPP NPs purified by dialysis.