Modification of heat-induced whey protein isolate hydrogel with highly bioactive glass particles results in promising biomaterial for bone tissue engineering

Michal Dziadek,Katarzyna Charuza,Radmila Kudlackova,Jenny Aveyard,Raechelle D'Sa,Andrada Serafim,Izabela-Cristina Stancu,Horia Iovu,Jemma G Kerns,Sarah Allinson,Kinga Dziadek,Piotr Szatkowski,Katarzyna Cholewa-Kowalska,Lucie Bacakova,Elzbieta Pamula,Timothy E.L Douglas

doi:10.1016/j.matdes.2021.109749

Abstract

This study deals with the design and comprehensive evaluation of novel hydrogels based on whey protein isolate (WPI) for tissue regeneration. So far, WPI has been considered mainly as a food industry by-product and there are very few reports on the application of WPI in tissue engineering (TE). In this work, WPI-based hydrogels were modified with bioactive glass (BG), which is commonly used as a bone substitute material. Ready-to-use, sterile hydrogels were produced by a simple technique, namely heat-induced gelation. Two different concentrations (10 and 20% w/w) of sol–gel-derived BG particles of two different sizes (2.5 and <45 µm) were compared. µCT analysis showed that hydrogels were highly porous with almost 100% pore interconnectivity. BG particles were generally homogenously distributed in the hydrogel matrix, affecting pore size, and reducing material porosity. Thermal analysis showed that the presence of BG particles in WPI matrix reduced water content in hydrogels and improved their thermal stability. BG particles decreased enzymatic degradation of the materials. The materials underwent mineralization in simulated biological fluids (PBS and SBF) and possessed high radical scavenging capacity. In vitro tests indicated that hydrogels were cytocompatible and supported MG-63 osteoblastic cell functions.

Highlights

Bone tissue is a natural composite with a complex, architectural structure and unique properties, which makes the design of a suitable replacement very demanding [1]
bioactive glass (BG) particles were generally homogenously distributed in the hydrogel matrix, affecting pore size, and reducing material porosity
Thermal analysis showed that the presence of BG particles in whey protein isolate (WPI) matrix reduced water content in hydrogels and improved their thermal stability

Summary

Introduction

Bone tissue is a natural composite with a complex, architectural structure and unique properties, which makes the design of a suitable replacement very demanding [1]. Various types of biomaterials have been used for bone regeneration [2]. Hydrogels have many advantages; they demonstrate comparable mechanical properties to soft tissues, and it is relatively easy to modify them and adjust their properties. The major disadvantages of these materials, from the point of view of bone tissue regeneration, are low mechanical strength and lack of bioactivity, i.e. the formation of a direct chemical bond with bone and promotion of the regeneration processes. Attempts to combine hydrogels with other components to improve these features and mimic the structure of natural bone tissue have been undertaken [3]

Methods

Results

Conclusion