Diamond in medical devices and sensors: An overview of diamond surfaces

Significant challenges arise when the human body is damaged, diseased and unable to repair itself. Current biomaterials for biomedical devices have limitations to restore function, while materials for implants and sensors often invoke a large foreign body response. Therefore, there is a need to develop suitable biomaterials in the fields of medical devices and sensors. Diamond is emerging due to its many favourable properties including biocompatibility, antimicrobial capability, antifouling properties, electrical conductivity and chemical functionalization capability. Thin film coatings of diamond can be fabricated by chemical vapour deposition, or by particle coatings with nanodiamond materials. Hybrid/composite diamond materials include soft materials such as those processed by electrospinning and melt extrusion, as well as hard materials such as those processed by additive manufacturing. Additive manufacturing is a developing area for diamond biomaterial fabrication and can include both hard and soft materials. The fabrication method used will depend on the properties required of the biomaterial, as well as the application. In this mini-review, recent progress on using diamond in medical devices and sensors is outlined, with particular emphasis on fabrication methods. We highlight selected applications from recent literature and, in closing, make comments and suggestions to advance the field and direction of diamond application in medical devices and sensors.