Near-IR absorbing gold nanostructures were prepared by a novel approach in the absence of any extra reducing agent, stabilizer or surface modification step through in-situ polymerization of an amine-containing monomer. Such nanoparticles can reversibly switch between hydrophilic and hydrophobic media using several triggers like temperature, pH and CO2/N-2 bubbling. (c) 2018 Elsevier Ltd. All rights reserved.