Quantitative evaluation of patterned self-assembled monolayers by color imaging of zeta-potential obtained from two-color fluorescence and evanescent wave illumination

A direct evaluation technique by color imaging of the zeta-potential for a substrate surface with material heterogeneity, sample adhesion and patterns of chemical coating and self-assembled monolayers (SAMs) was developed. This technique employed two-color fluorescence excited by the evanescent wave for the zeta-potential measurement. The experiments were conducted to evaluate the monolayers of octadecyltrichrolosilane patterned on the glass surface. The color mapping of wall zetapotential of SAMs patterned on the microchannel wall was achieved, which has not been realized by the conventional techniques focusing on thickness and structure of molecules and wettability.