Table 1.

Summary of most common molecules on the surface of a biomedical implant, and the consequences of the presence of these groups

Group	Hydrophobicity	Charge	Action in the body	Reference
—CH3 (methyl)	Hydrophobic	Neutral	Inflammatory response, increased scar thickness	[ 130 ]
—NH2 (amino)	Hydrophilic	Positive	Inflammation, cell infiltration, fibrotic reactions	[ 131 , 132 ]
—OH (hydroxyl)	Hydrophilic	Neutral	Inflammation, cell infiltration, fibrotic reactions	[ 131 , 133 ]
—COOH (carboxyl)	Hydrophilic	Negative	Glial scarring and cell infiltration	[ 131 ]