Preparation and Characterization of PVA/PVP/CS Bionic Hydrogels

Area of Science:

• Biomaterials Science
• Polymer Chemistry
• Biomedical Engineering

Background:

• Poly(vinyl alcohol) (PVA) hydrogels possess biomimetic properties but differ significantly from natural oral soft tissues in mechanical and surface characteristics within simulated oral environments.
• Developing enhanced PVA hydrogels is crucial for creating effective oral substitutes that accurately mimic native tissue properties.

Purpose of the Study:

• To engineer a novel composite hydrogel based on PVA, polyvinylpyrrolidone (PVP), and chitosan (CS) with properties suitable for simulating oral soft tissue.
• To investigate the effects of a specific preparation strategy on the surface, mechanical, lubrication, and biocompatibility characteristics of the modified PVA hydrogels.

Main Methods:

• Preparation of PVA/PVP (APV) hydrogels via solvent exchange using DMSO, followed by cross-linking with chitosan (CS) to form PVA/PVP/CS (PPC) composite hydrogels.
• Comprehensive evaluation of APV and PPC hydrogels, including tensile strength, compression modulus, surface wettability (water contact angle), lubrication performance (friction coefficient), and in vitro biocompatibility (cell viability).

Main Results:

• Solvent exchange with DMSO enhanced the cross-linking density of PVA and PVP, with a PVA/PVP ratio of 3:1 yielding optimal tensile properties in APV hydrogels.
• PPC hydrogels demonstrated a 212% increase in compression modulus compared to PVA hydrogels, closely matching human tongue tissue.
• PPC hydrogels exhibited significantly improved superhydrophilicity (water contact angle of 27.07° for PPC2) and lubrication (62% reduction in friction coefficient for PPC2 vs. APV), maintaining stability in simulated oral conditions.
• PPC hydrogels showed enhanced biocompatibility, with a MC3T3-E1 cell survival rate of 96.18% in PPC extract after 48 hours.

Conclusions:

• The developed preparation strategy effectively enhances the comprehensive properties of PVA hydrogels, particularly mechanical strength, lubrication, and surface characteristics, without compromising biocompatibility.
• The bionic PVA/PVP/CS composite hydrogels show significant promise as advanced materials for oral substitute applications, offering valuable insights for future biomaterial development.