A pH-responsive surface has been fabricated by chemisorption of HS(CH2)(9)CH3 and HS(CH2)(10)COOH in an appropriate ratio onto a fractal-like gold structure. ne surface exhibits superhydrophobicity in an acidic environment and superhydrophilicity under basic conditions. The Figure (right, top) shows an acid droplet on the gold surface, while the image below it shows a base droplet.