We have developed a modified nanosphere lithography (NSL) process to fabricate surface-confined Ag nanoparticles (NPs) with controlled shapes. NPs with different shapes, such as triangular, quadrilateral, pentagon or trapezoidal with rounded tips or edges, can be fabricated by this process. These Ag NPs can be dislodged into water forming NPs in an aqueous environment. The developed process results in better NP shape retaining than those obtained using the routine NSL process. The UV-vis absorption of the surface-confined Ag NPs show distinct blue shift and reduced intensity after surface modi. cation. The NPs produced by the modified NSL and dislodged in water have significantly less density of debris as observed by transmission electron microscopy and UV-vis absorption spectrum. (C) 2010 Elsevier B. V. All rights reserved.