PVA-Based Hydrogels Loaded with Diclofenac for Cartilage Replacement

Abstract

Polyvinyl alcohol (PVA) hydrogels have been widely studied for cartilage replacement due to their biocompatibility, chemical stability, and ability to be modified such that they approximate natural tissue behavior. Additionally, they may also be used with advantages as local drug delivery systems. However, their properties are not yet the most adequate for such applications. This work aimed to develop new PVA-based hydrogels for this purpose, displaying improved tribomechanical properties with the ability to control the release of diclofenac (DFN). Four types of PVA-based hydrogels were prepared via freeze-thawing: PVA, PVA/PAA (by polyacrylic acid (PAA) addition), PVA/PAA+PEG (by polyethylene glycol (PEG) immersion), and PVA/PAA+PEG+A (by annealing). Their morphology, water uptake, mechanical and rheological properties, wettability, friction coefficient, and drug release behavior were accessed. The irritability of the best-performing material was investigated. The results showed that the PAA addition increased the swelling and drug release amount. PEG immersion led to a more compact structure and significantly improved the material’s tribomechanical performance. The annealing treatment led to the material with the most suitable properties: besides presenting a low friction coefficient, it further enhanced the mechanical properties and ensured a controlled DFN release for at least 3 days. Moreover, it did not reveal irritability potential for biological tissues.

Formulation and Evaluation of Diclofenac Potassium Gel in Sports Injuries with and without Phonophoresis

“…Any comparison of the current study’s results with other intervention programs for soft tissue injuries to assess the effectiveness of DK gel compared to other established products is hampered by differences in study design, inclusion criteria, duration of treatment, and efficacy assessment methods. Furthermore, in recent years, a variety of biomaterials (e.g., patches-based hydrogels, cryogels, nanofibers) together with their distinct physicochemical features have been extensively investigated and developed in the fields of drug-delivery, tissue engineering, medicine, and public health, including disease diagnosis [ 21 , 41 , 42 , 43 , 44 , 45 , 46 , 47 , 48 , 49 ]. Thereby, a most recent study in rabbits has reported an injectable thermosenstive hydrogel for dual delivery of diclofenac and avastin (an anti-VEGF) to reduce the inflammation of the corneal neovascularization more effectively [ 49 ].…”

Adhesive hydrogels in osteoarthritis: from design to application

“…In biological tissue, hydrogen bonding often occurs between N and O [ 52 ]. Typically, the hydrogen bonding in adhesive hydrogels for OA therapy comes from polymers with plenty of hydroxyl groups, such as polyvinyl alcohol (PVA) [ 53 – 55 ].…”

Advanced injectable hydrogels for cartilage tissue engineering

“…Both histomorphology and radiology showed regeneration of cartilage defects. Branco et al (2022) prepared an injectable PVA-based hydrogel that continuously released diclofenac for cartilage regeneration. Some of the following drugs are also used in injectable hydrogels to repair cartilage damage.…”