Haemocompatibility evaluation of DLC- and SiC-coated surfaces

Area of Science:

• Biomaterials Science
• Surface Engineering
• Medical Device Development

Background:

• Biomedical devices require surfaces with excellent hemocompatibility to prevent adverse blood reactions.
• Diamond-like carbon (DLC) and silicon carbide (SiC) coatings offer desirable properties like low friction and high hardness for biomedical applications.

Purpose of the Study:

• To evaluate the in vitro hemocompatibility of DLC and SiC coatings on silicon wafer and silicone rubber substrates.
• To compare the hemocompatibility of coated surfaces against various control materials.

Main Methods:

• Plasma-enhanced chemical vapor deposition (PE-CVD) was used to apply DLC and SiC coatings.
• Surface characterization included ATR-FTIR and contact angle measurements.
• In vitro hemocompatibility was assessed through thrombin generation, platelet adhesion, and complement convertase activity assays.

Main Results:

• DLC coatings on both silicon wafer and silicone rubber demonstrated superior hemocompatibility, delaying coagulation and inhibiting platelet and complement activation.
• SiC-coated silicon wafers were found to be thrombogenic.
• Hemocompatibility ranking from most to least: Si(rub)/ DLC-Si(rub)/ DLC-Si(waf)/ LDPE/ PDMS/ SiC-Si(waf)/ Si(waf)/ PMMA/ MS.

Conclusions:

• DLC coatings represent a promising surface modification for enhancing the hemocompatibility of biomedical devices.
• SiC coatings on silicon wafers are not suitable for blood-contacting applications due to their thrombogenic nature.
• This study provides a critical in vitro assessment to guide the selection of biomaterials for further in vivo investigations.