부산대학교 도서관

Tris(hydroxymethyl)aminomethane (Tris) has been used as the buffer in bioactivity testing for over two decades and has become a standard choice for the scientific community. While it is believed to be non-interacting, the extent of its interactions with titanium oxide surfaces has not been systematically studied. Here, we use experimental (zeta potential measurements) and computational (molecular dynamics) approaches to evaluate the interaction of Tris with a rutile surface and how it affects the adsorption of other molecules relevant in biomedical in vitrotesting. We show that the interaction of Tris with the rutile surface is strong and significantly affects the interaction of other organic residues with the surface. These strong interactions are compounded by the Tris concentration in the in vitrotesting protocol which is much higher compared to other components. Our findings indicate that the kinetics observed in in vitrotests will be strongly influenced by the presence of Tris as a buffering agent when compared to the natural CO2buffer in blood. These results reveal that considering the so-far neglected active role of Tris in in vitrotesting is critically needed and that in vitroprotocols using CO2partial pressure as the buffering agent should yield more reliable results.