Self-assembled Monolayers for Controllable Adhesion of DOPA

11-Mercapto-1-undecanol and 1-dodecyl mercaptan with -OH or -CH3 as capping groups respectively were self. assembled onto gold surfaces at molar ratios of 1 : 0, 3 : 1, 1 : 1, 1 : 3 and 0 : 1, preparing binary monolayers with various hydrophilic. hydrophobic properties and chemical compositions. The mono. layers were characterized by X-ray photoelectron spectroscopy(XPS), contact angle(CA) and atomic force microscope(AFM) methods. The adhesion properties of dopa and liquid phase environment-related water droplets against self. assembled monolayers(SAMs) were also investigated. It can be found that the OH. terminated SAMs had the most superior anti. dopa adhesion ability. With the molar ratio decrease of -OH groups and the introduction of the -CH3 groups on the surface, the adhesion ability of dopa to the surface is increased. Fur. thermore, the pure OH-terminated SAMs showed a strongest droplet adhesion performance, and with the molar ratio of -OH groups decreasing, the droplet adhesion to the surface become weak. The introduction of the -CH3 groups significantly reduced the surface water adhesion. The experimental results showed that the OH-or CH3-terminated SAMs is difficult to possess anti-dopa and droplet-adhesion properties at the same time and the adhesion ability of the binary mixed SAMs can be adapted to a specific environment, which proposed a new concept for the design and preparation of anti. adhesion materials.