Preparation of Polymer@AuNPs with Droplets Approach for Sensing Serum Copper Ions

Abstract

A microfluidic droplet synthesis approach for the preparation of poly N-isopropylacrylamide protected gold nanoparticles (PNIPAm@AuNPs) was presented here. Well-dispersed PNIPAm@AuNPs could be generated within 8 min. On the basis of the aggregation-induced UV-vis adsorption intensity increasing mechanism, the PNIPAm@AuNPs-based colorimetric probe displayed high sensitivity and good selectivity for sensing copper ions. A linear calibration of relative UV-vis adsorption intensity increasing versus copper ions concentration was obtained within 5.0-750.0 μM, and the limit of detection was 2.5 μM. Furthermore, after copper ions were injected in rat, a metabolic assay was developed with the proposed probe. The results indicated that the droplet microfluidic synthesis system could provide a new way for preparation of polymer@AuNPs with good polydispersity index and showed great potential of polymer@AuNPs-based sensing probe for application in biological and clinical analysis.

Simultaneous Monitoring of Temperature and Ca2+ Concentration Variation by Fluorescent Polymer during Intracellular Heat Production

“…PNIPAm was synthesized using the reversible addition–fragmentation chain transfer (RAFT) polymerization method (SI Figure S1) using a homemade droplet-based microreactor (SI Figure S2). First, PNIPAm was obtained with Mw gpc of 9.6 kDa and PDI of 1.2, which verified by gel permeation chromatography (GPC). PNIPAm was employed as the macro transfer agent in further polymerization of PNIPAm-VPBA (SI Figure S3).…”

Impact of Temperature on the Fusion Growth of Bimetallic Au–Pt Nanoparticles from Each Nanocluster Conjugated with a Thermoresponsive Polymer

“…23 For the growth of neat gold (Au) NPs, the reduction step of tetrachloroauric(III) acid, [AuCl 4 ] − , is widely applied to the chemical synthesis processes, 24 including polymer-assisted preparation methods. 25,26 In contrast, we have discovered a chemical synthesis method uniquely from Au nanoclusters (NCs) without the need for a reduction step during the NP formation. 27 In this method, the structural collapse of a thermoresponsive polymer via a random coil−globule transition is applied to the NP formation, hereafter referred to as thermally induced fusion growth.…”

Functionalized gold nanoparticles for sample preparation: A review

“…Using polymer coatings as intermediate layers for ligand immobilization is a common strategy for GNP surface modification. On the one hand, the long‐chain structure of neutral polymers can induce steric hindrance to van der Waals driven aggregation and therefore may cause enhanced colloidal stability of GNPs . On the other hand, ionic polymer (polyelectrolyte) coatings are of particular interest due to their highly abundant charges which usually improve the colloidal stability of GNPs by the enhanced repulsive electrostatic interactions according to the DLVO theory (named after Derjaguin, Landau, Verwey, and Overbeek who developed a theory describing colloidal stability) .…”