Bioactive Composite Cryogels Based on Poly (Vinyl Alcohol) and a Polymacrolactone as Tissue Engineering Scaffolds: In Vitro and In Vivo Studies

Development and characterization of PVA-zein/α-tocopherol nonwoven mats for functional wound dressing applications

Wound healing poses significant clinical challenges due to issues like bacterial infections, oxidative stress, and the need for sustained therapeutic delivery. This study aimed to develop and characterize biocompatible nonwoven fibrous mats composed of poly(vinyl alcohol) (PVA) and zein encapsulating α-tocopherol for wound dressing applications. α-Tocopherol was nano-encapsulated in zein proteins using an antisolvent co-precipitation method, followed by its dispersion in PVA solutions. The resulting composition was then processed using a novel, scalable, and inexpensive solution blow spinning (SBS) process that offers higher throughputs to generate non-woven mats. The resulting fibers in the non-woven mats, ranging in diameter from 350 nm to 796 nm, demonstrate uniform morphology, as confirmed by scanning electron microscopy. Fourier transform infrared (FTIR) spectroscopy validated the successful incorporation of α-tocopherol without altering the chemical structure of the PVA-zein matrix. Rheological assessments revealed Newtonian behavior and a decrease in viscosity with higher tocopherol content, enhancing the processability of the mats. Mechanical testing showed that increasing tocopherol content improved tensile strength, elongation, and Young's modulus. The mats exhibited a biphasic release profile with an initial burst and sustained α-tocopherol release over 24 h, fitting the Korsmeyer-Peppas model and hence indicating a diffusion-controlled mechanism. Cytotoxicity assays confirmed high cell viability (>90 %) and enhanced cell spreading, underscoring their biocompatibility. These findings suggest that PVA-zein/tocopherol fiber mats are promising candidates for functional wound dressing materials, offering sustained antioxidant activity and a favorable wound healing environment. Future work will focus on optimizing fiber composition for antimicrobial properties and conducting in vivo studies to validate their clinical efficacy.

Recent Advances in Poly(vinyl alcohol)-Based Hydrogels

Poly(vinyl alcohol) (PVA) is a versatile synthetic polymer, used for the design of hydrogels, porous membranes and films. Its solubility in water, film- and hydrogel-forming capabilities, non-toxicity, crystallinity and excellent mechanical properties, chemical inertness and stability towards biological fluids, superior oxygen and gas barrier properties, good printability and availability (relatively low production cost) are the main aspects that make PVA suitable for a variety of applications, from biomedical and pharmaceutical uses to sensing devices, packaging materials or wastewater treatment. However, pure PVA materials present low stability in water, limited flexibility and poor biocompatibility and biodegradability, which restrict its use alone in various applications. PVA mixed with other synthetic polymers or biomolecules (polysaccharides, proteins, peptides, amino acids etc.), as well as with inorganic/organic compounds, generates a wide variety of materials in which PVA's shortcomings are considerably improved, and new functionalities are obtained. Also, PVA's chemical transformation brings new features and opens the door for new and unexpected uses. The present review is focused on recent advances in PVA-based hydrogels.

Exploring Skin Wound Healing Models and the Impact of Natural Lipids on the Healing Process

Cutaneous wound healing is a complex biological process involving a series of well-coordinated events aimed at restoring skin integrity and function. Various experimental models have been developed to study the mechanisms underlying skin wound repair and to evaluate potential therapeutic interventions. This review explores the diverse array of skin wound healing models utilized in research, ranging from rodent excisional wounds to advanced tissue engineering constructs and microfluidic platforms. More importantly, the influence of lipids on the wound healing process is examined, emphasizing their role in enhancing barrier function restoration, modulating inflammation, promoting cell proliferation, and promoting remodeling. Lipids, such as phospholipids, sphingolipids, and ceramides, play crucial roles in membrane structure, cell signaling, and tissue repair. Understanding the interplay between lipids and the wound microenvironment provides valuable insights into the development of novel therapeutic strategies for promoting efficient wound healing and tissue regeneration. This review highlights the significance of investigating skin wound healing models and elucidating the intricate involvement of lipids in the healing process, offering potential avenues for improving clinical outcomes in wound management.