PVA-based hydrogels loaded with diclofenac for cartilage replacement

Branco A.C.; Oliveira A.S.; Monteiro I.; Nolasco P.; Silva D.C.; Figueiredo-Pina C.G.; Colaço R.; Serro A.P.

Key information

Authors:

Branco A.C. (Ana Catarina Moreno Branco); Oliveira A.S. (Andreia Sofia Gonçalves de Oliveira); Monteiro I.; Nolasco P. (Pedro de Almeida Nolasco); Silva D.C. (Diana Cristina Morais da Silva); Figueiredo-Pina C.G.; Colaço R. (Rogério Anacleto Cordeiro Colaço); Serro A.P. (Ana Paula Valagão Amadeu do Serro)

Published in

February 24, 2022

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.