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The aim of the present work was to obtain drug-loaded hydrogels based on combinations of dextran, chitosan/gelatin/xanthan, and poly (acrylamide) as a sustained and controlled release vehicle of Doxorubicin, a drug used in skin cancer therapy that is associated with severe side effects. Hydrogels for use as 3D hydrophilic networks with good manipulation characteristics were produced using methacrylated biopolymer derivatives and the methacrylate group’s polymerization with synthetic monomers in the presence of a photo-initiator, under UV light stimulation (365 nm). Transformed infrared spectroscopy analysis (FT-IR) confirmed the hydrogels’ network structure (natural–synthetic composition and photocrosslinking), while scanning electron microscopy (SEM) analysis confirmed the microporous morphology. The hydrogels are swellable in simulated biological fluids and the material’s morphology regulates the swelling properties: the maximum swelling degree was obtained for dextran–chitosan-based hydrogels because of their higher porosity and pore distribution. The hydrogels are bioadhesive on a biological simulating membrane, and values for the force of detachment and work of adhesion are recommended for applications on skin tissue. The Doxorubicin was loaded into the hydrogels and the drug was released by diffusion for all the resulting hydrogels, with small contributions from the hydrogel networks’ relaxation. Doxorubicin-loaded hydrogels are efficient on keratinocytes tumor cells, the sustained released drug interrupting the cells’ division and inducing cell apoptosis; we recommend the obtained materials for the topical treatment of cutaneous squamous cell carcinoma.

Knee Osteoarthritis (KOA), the most common knee degenerative disease, involve a slow destructive process, leading to disability and ultimately total knee replacement. The progression of KOA is related to the loss of rheological properties of the synovial fluid (SF), due to slow immunological, inflammatory and enzymatic processes that cleave the hyaluronic acid (HA) and decrease the concentration of specific proteins. Since no effective treatments have been found to halt the progression of KOA, injection of HA-based viscoelastic gels combined with physiotherapy (PT) is an alternative to symptomatic therapies. In order to evaluate the effect of viscosupplementation and PT on the SF characteristics, the SF aspirated from the KOA was spectrophotometrically and rheological analyzed, comparing the receiving groups of HA Kombihylan® and groups that received Kombihylan® and complex PT. In patients treated with PT, SF extracted 6 weeks after viscosupplementation had a superior elastic moduli (G') and viscous moduli (G") profile behavior, having a homogeneous distribution of proteins and polysaccharides in the SF, stimulating stronger interactions. In the absence of PT the G' and G" profiles are non-uniform, suggesting an unorganized supplemented SF with some clustering phenomena, proteins aggregation and a low level of entanglement between HA and macromolecular components in the SF.

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