ENDOTHELIAL-CELL GROWTH AND PROTEIN ADSORPTION ON TERMINALLY FUNCTIONALIZED, SELF-ASSEMBLED MONOLAYERS OF ALKANETHIOLATES ON GOLD

The effect of specific chemical functionalities on the growth of bovin e aortic endothelial cells (BAEC) was investigated using a set of well -characterized, chemically functionalized surfaces prepared by self-as sembly of alkanethiolate monolayers on gold surfaces using the molecul es X(CH2)(15)SH with X = -CH3, -CH2OH, -CO2CH3, and -CO2H. Cells seede d on a substrate in serum-containing culture medium interact with the adsorbed protein layer rather than the substrate. Therefore, the role of two serum proteins, albumin (Alb) (a nonadhesive or blocking protei n) and fibronectin (Fn) (an adhesive protein), in cell growth was eval uated by measuring the amount of each protein bound and the tightness of binding (determined by resistance to SDS solubilization) on the sel f-assembled monolayers (SAMs). BAEC growth varied significantly with s urface functionality. Cell growth increased in the following order: -C H2OH < -CO2CH3 < -CH3 much less than -CO2H, illustrating the effect of specific surface groups. Cell growth on all monolayer surfaces was lo wer than on tissue culture polystyrene suggesting that multiple chemic al functionalities may be desirable for cell growth. Protein interacti on studies demonstrated variations in protein adsorption and elutabili ty in response to the SAM terminal functional group. Alb adsorption an d Fn elutability did not differ significantly with terminal functional group. The best cell growth substrate (COOH SAM) demonstrated signifi cantly higher Fn adsorption and Alb elutability than did the poor grow th substrates (CO2CH3 and OH SAMs).