Modification Techniques for Improved Properties of Silicones in Biomedical Applications

3 Modification Techniques for Improved Properties of Silicones in Biomedical Applications 

The main methods used for modification of polydimethylsi-loxanes, in order to improve their properties for biomaterials 

For long-term implcuitation, PDMS behaves is cui inert material, causing a minimal foreign body reaction. The longterm tissue reaction is chcffacterized by the development of 

Diverse approaches have been considered in an attempt to enhance the cell attachment to the surface of PDMS implants [60]. In general, techniques that involve modification of the material surface are preferred to preserve the bulk properties. Chemical and physical surface modification methods, such as bonding of molecules, grafting of polymers and coating with bioactive materials, have shown different degrees of success over recent years. 

Laser-induced surface grafting of poly(HEMA) and a sequential method for preparation of NPNs of PDMS/ poly(HEMA) were used by Abbasi et al. [79] for surface and bulk modifications, respectively. Data from in-vitro results showed that platelet adhesion is greatly reduced by the surface graft polymerization of HEMA in comparison with the control sample. The above research team concluded that if other functions are not required, surface modification may be preferred to bulk modification however, for the design of PDMS devices with potential for limited swelling, bulk modification may be preferred to surface modification. 

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