Bacteria and osteoblast adhesion to chitosan immobilized titanium surface: A race for the surface

Bacteria and osteoblast adhesion behavior on chitosan immobilized titanium surface in co-culture systems simulating “race for the surface”. [Display omitted] •Titanium surface was immobilized with chitosan: SA-CS-Ti.•Two bacteria/osteoblast co-culture systems were proposed and established.•The co-culture systems were used for testing the race for the surface behavior.•The SA-CS-T is decreased bacteria and increased osteoblast adhesions simultaneously. In order to evaluate the anti-infective efficacy of the titanium implant materials, two co-culture systems, a low-bacteria/osteoblast (L-B) and a high-bacteria/osteoblast system (H-B), were established. Untreated (UN-Ti), sulfuric acid-treated (SA-Ti), and chitosan immobilized titanium (SA-CS-Ti) materials were developed and evaluated. Bacteria and osteoblast behaviors, including initial attachment (evaluated at 30mins), adhesion (evaluated at 4h), and osteoblast spreading on each material surface were evaluated using quantification assays, scanning electron microscopy (SEM), and confocal microscopy. Quantification analysis at 30mins showed significantly higher number of osteoblast present on SA-CS-Ti in both L-B (10,083±2626) and H-B (23,592±2233) than those on the UN-Ti (p