In this study, Au nanoparticle (5 nm) colloid was employed for a facile preparation of SERS substrates from three approaches: (1) original Au nanoparticles, (b) Au colloid coated 200 nm polystyrene (PS) beads, and (3) Au colloid annealed at 200-500 degrees C. Rhodamine 6G (R6G) and crystal violet were employed as the Raman active probes. The Au colloid deposited PS beads (PS@Au) exhibit intensive SERS signal for R6G detection, which is promising for crystal violet detection after being annealed at 400 degrees C. The 200 degrees C annealed Au nanoparticles demonstrate excellent combined SERS sensitivity for both R6G and crystal violet. For the original Au colloid, elevated annealing temperature from 200 degrees C to 500 degrees C decreases the SERS intensity as Au particles were coarsened gradually. (C) 2015 Elsevier B.V. All rights reserved.