Liposomes Affect Protein Release and Stability of ITA-Modified PLGA-PEG-PLGA Hydrogel Carriers for Controlled Drug Delivery.

Fat grafting, a key regenerative medicine technique, often requires repeat procedures due to high-fat reabsorption and volume loss. Addressing this, a novel drug delivery system uniquely combines a thermosensitive, FDA-approved hydrogel (itaconic acid-modified PLGA-PEG-PLGA copolymer) with FGF2-STAB, a stable fibroblast growth factor 2 with a 21-day stability, far exceeding a few hours of wild-type FGF2's stability. Additionally, the growth factor was encapsulated in "green" liposomes prepared via the Mozafari method, ensuring pH protection. The system, characterized by first-order FGF2-STAB release, employs green chemistry for biocompatibility, bioactivity, and eco-friendliness. The liposomes, with diameters of 85.73 ± 3.85 nm and 68.6 ± 2.2% encapsulation efficiency, allowed controlled FGF2-STAB release from the hydrogel compared to the unencapsulated FGF2-STAB. Yet, the protein compromised the carrier's hydrolytic stability. Prior tests were conducted on model proteins human albumin (efficiency 80.8 ± 3.2%) and lysozyme (efficiency 81.0 ± 2.7%). This injectable thermosensitive system could advance reconstructive medicine and cosmetic procedures.

Matching Low Viscosity with Enhanced Conductivity in Vat Photopolymerization 3D Printing: Disparity in the Electric and Rheological Percolation Thresholds of Carbon-Based Nanofillers Is Controlled by the Matrix Type and Filler Dispersion.

This study investigated the impact of carbonaceous fillers (carbon black, multiwalled carbon nanotubes, graphene, and highly defective graphene) on aromatic and nonaromatic photopolymer resins' properties, such as viscosity, long-term stability, complex permittivity, curing efficiency, final conversion, storage modulus, heat deflection and glass transition temperatures, network density, and DC resistivity. The presented results also highlight challenges that must be addressed in designing and processing carbonaceous filler-based 3D-printed photopolymer resins. The improved dielectric and electrical properties were closely tied to the dispersion quality and filler-matrix affinity. It favored the enhanced dispersion of anisotropic fillers (nanotubes) in a compatible matrix above their percolation threshold. On the other hand, the dispersed filler worsens printability due to the elevated viscosity and deteriorated penetration depth. Nonetheless, electrical and rheological percolation was found at different filler concentrations. This window of despaired percolation combines highly enhanced conductivity with only mildly increased viscosity and good printability.