Surface-enhanced Raman encoded polymer stabilized gold nanoparticles: Demonstration of potential for use in bioassays

Abstract

The preparation of biotinylated, self-assembled polymer stabilized gold nanoparticle hybrids encoded with a SERS active compound is described. The polymers used for nanoparticle stabilization are carefully designed for this purpose and are synthesized by the RAFT polymerization process, as the thiocarbonylthio end group provides a functional handle for anchoring the polymers to the gold surface. Functionalised biotin moieties are attached to the hybrid nanoparticles via Cu-catalyzed azide-alkyne cycloaddition. Binding of the biotinylated hybrid nanoparticles to streptavidin was confirmed by nanoparticle detection and identification by the SERS spectrum of the surface-bound SERS active compound, quinolinethiol. This investigation includes the requisites that constitute a bioassay, demonstrating the potential of polymer-coated hybrid nanoparticles for this purpose

Improved Electro- and Photocatalytic Water Reduction by Confined Cobalt Catalysts in Streptavidin

“…26a Ethyl [(3aS,4S,6aR)-2oxo-hexahydrothieno[3,4-d]imidazole-4-yl]pentanoate ( COOEt Biotin) was synthesized following the reported method from the literature. 31 Anhydrous acetonitrile was purchased from Scharlab. Water (18.2 MΩ•cm) was purified with a Milli-Q Millipore Gradient AIS system.…”

“…Photosensitizer [Ir­(bpy)­(ppy) 2 ]­PF 6 ( PS Ir ) was synthesized according to literature procedures . Ethyl [(3a S ,4 S ,6a R )-2-oxo-hexahydrothieno­[3,4-d]­imidazole-4-yl]­pentanoate ( COOEt Biotin ) was synthesized following the reported method from the literature . Anhydrous acetonitrile was purchased from Scharlab.…”

Polymer@gold Nanoparticles Prepared via RAFT Polymerization for Opto-Biodetection

“…Thus, the polarization of molecules adsorbed at the surface of the NP are also affected resulting in an enhancement of the Raman scattering signal, allowing the identification of such molecular species even in very diluted conditions [ 140 , 141 , 142 ]. The importance of polymer/Au nanocomposites in the preparation of these diagnosis platforms also results from the colloidal stabilization and chemical functionalization conferred by the polymer shells, namely when they are intended to be used in complex environments such as real biological samples [ 141 , 142 , 143 ] RAFT-polymer/Au nanocomposites have been prepared aiming the preparation of nanoassemblies, in which the NPs become close to each other, thus creating “hot spots” that result in improved SERS signals [ 144 ].…”

Recent Appointees in Polymer Science special issue

“…This special issue highlights the breadth and depth of the polymer science research carried out by the RAPS community, which goes from the synthesis and characterisation of polymers, 1 nanoparticles 2,3 and hydrogels, 4,5 to the characterisation of the solution 6 and physical 7 properties of polymeric materials. The applications discussed range from drug and gene delivery, 2,5,8 to sensing 3 and a review of the methods used to modify the properties of epoxy resins. 9 RAPS vision in these changing times is that the need to establish and support international collaboration is more important than ever.…”