Nichol T, Callaghan J, Townsend R, et al. - This study was sought to construct a single-layer hybrid organic-inorganic sol-gel coating that is capable of a controlled antibiotic release for cementless hydroxyapatite-coated titanium orthopedic prostheses. Researchers prepared and tested coatings containing gentamicin at a concentration of 1.25% weight/volume (wt/vol), similar to that found in commercially available antibiotic-loaded bone cement in the laboratory for: kinetics of antibiotic release; activity against planktonic and biofilm bacterial cultures; biocompatibility with cultured mammalian cells; and physical bonding to the material (n = 3 in all tests). They investigated sol-gel coatings and controls in vivo in a small animal healing model (four materials tested; n = 6 per material), and applied to the surface of commercially pure HA-coated titanium rods. They present a new sol-gel technology that can release gentamicin from a bioceramic-coated cementless arthroplasty material. Local gentamicin levels are in excess of what can be achieved by antibiotic-loaded bone cement in vitro. Bone healing in an animal model is not impaired in vivo. This, therefore, represents a biomaterial modification that may have the potential to protect at-risk individuals from implant-related deep infection.