title: Biocompatibility studies of low temperature nitrided and collagen-I coated AISI 316L austenitic stainless steel.
abstract: The biocompatibility of austenitic stainless steels can be improved by means of surface engineering techniques. In the present research it was investigated if low temperature nitrided AISI 316L austenitic stainless steel may be a suitable substrate for bioactive protein coating consisting of collagen-I. The biocompatibility of surface modified alloy was studied using as experimental model endothelial cells (human umbilical vein endothelial cells) in culture. Low temperature nitriding produces modified surface layers consisting mainly of S phase, the supersaturated interstitial solid solution of nitrogen in the austenite lattice, which allows to enhance surface microhardness and corrosion resistance in PBS solution. The nitriding treatment seems to promote the coating with collagen-I, without chemical coupling agents, in respect of the untreated alloy. For biocompatibility studies, proliferation, lactate dehydrogenase levels and secretion of two metalloproteinases (MMP-2 and MMP-9) were determined. Experimental results suggest that the collagen protection may be favourable for endothelial cell proliferation and for the control of MMP-2 release.
authors.affiliation: Department of Biomedical, Experimental and Clinical Sciences, University of Florence, Viale Morgagni 50, 50134 Florence, Italy.
authors.forename: M
authors.initials: M
authors.lastname: Martinesi
authors.forename: M
authors.initials: M
authors.lastname: Stio
authors.forename: C
authors.initials: C
authors.lastname: Treves
authors.forename: F
authors.initials: F
authors.lastname: Borgioli
mesh_terms: D049109:Cell Proliferation / Q000187:drug effects; D002470:Cell Survival / Q000187:drug effects; D020099:Coated Materials, Biocompatible / Q000138:chemical synthesis* / Q000494:pharmacology*; D024042:Collagen Type I / Q000737:chemistry / Q000494:pharmacology*; D042783:Endothelial Cells / Q000166:cytology / Q000187:drug effects* / Q000502:physiology*; D006801:Humans; D008422:Materials Testing; D009573:Nitrites / Q000737:chemistry*; D013193:Stainless Steel / Q000737:chemistry*; D013696:Temperature
chemical_list: D020099:Coated Materials, Biocompatible; D024042:Collagen Type I; D009573:Nitrites; C426023:austenitic steel; D013193:Stainless Steel