Different types of healing agents have already been tested on their efficiency for use in self-healing cementitious materials. Generally, commercial healing agents are used while their properties are adjusted for manual crack repair and not for autonomous crack healing. Consequently, the amount of regain in properties due to self-healing of cracks is limited. In this research, a methyl methacrylate (MMA)-based healing agent was developed specifically for use in self-healing cementitious materials. Various parameters were optimized including the viscosity, curing time, strength, etc. After the desired properties were obtained, the healing agent was encapsulated and screened for its self-healing efficiency. The decrease in water permeability due to autonomous crack healing using MMA as a healing agent was similar to the results obtained for manually healed cracks. First results seem promising: however, further research needs to be undertaken in order to obtain an optimal healing agent ready for use in practice.

This study was performed to determine the in vitro biocompatibility of a bioactive, antibacterial silver based gel. A human osteoblast-like cell line (HOS TE85) was used to test cytocompatibility in the presence of eluants and the biological response in direct contact with Na(2)O.CaO.2SiO(2) gel (containing 0.5050 wt % Ag(2)O prepared by a sol-gel process) sterilized by two different methods; autoclave and gamma-irradiation. MTT assay was used for the indirect evaluation of eluant toxicity and alamar Blue was performed to assess the biological response, which included cell viability and proliferation, and the results showed that these materials were cytocompatible.

Poly(2-hydroxyethyl methacrylate) pHEMA is a widely used hydrogel for several biomedical applications, however, cell adhesion and proliferation are limited in these polymers. In this study the strategy of phosphate containing monomer based copolymerisation has been used to molecularly engineer poly(2-hydroxyethyl methacrylate) hydrogels. Ethylene glycol methacrylate phosphate EGMP, a proton conducting electrolyte, was copolymerised with HEMA and incorporated at varying monomer feed ratios to enhance the swelling dynamics and improve the ability of pHEMA based hydrogel sponges to facilitate cell adhesion and mineralization and hence expand their biomedical application. The hydration of the copolymer gels showed that there was a direct correlation to the amount of EGMP incorporated within the polymeric network and the degree of hydration increased with increasing concentration of EGMP. EGMP in its polymeric form is a polyelectrolyte due to the readiness of the pendant phosphate group to ionise in low or high pH solution. Evaluation of the thermal behaviour showed that T g increased with increasing EGMP and although presence of water influenced transitions within these novel EGMP polymer networks, it did not have a deteriorating effect on the stiffness within the target temperature range even when fully hydrated. Furthermore, the damping or energy dissipation of the system increases in the ambient body temperature range, which is of particular interest for in vivo use.

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