Organotrialkoxysilane-Functionalized Noble Metal Monometallic, Bimetallic, and Trimetallic Nanoparticle Mediated Non-Enzymatic Sensing of Glucose by Resonance Rayleigh Scattering.

Prem C Pandey,Shubhangi Shukla,Murli Dhar Mitra,Roger J Narayan

doi:10.3390/bios11040122

Abstract

Organotrialkoxysilanes like 3-aminopropyltrimethoxysilane (3-APTMS)-treated noble metal cations were rapidly converted into their respective nanoparticles in the presence of 3-glycidoxypropylytrimethoxysilane (3-GPTMS). The micellar activity of 3-APTMS also allowed us to replace 3-GPTMS with other suitable organic reagents (e.g., formaldehyde); this approach has significant advantages for preparing bimetallic and trimetallic analogs of noble metal nanoparticles that display efficient activity in many practical applications. The formation of monometallic gold, silver, and palladium nanoparticles, bimetallic Ag-Pd, and Au-Pd nanoparticles at various ratios of noble metal cations, and trimetallic Ag-Au-Pd nanoparticles were studied; their biocatalytic activity in non-enzymatic sensing of glucose based on monitoring synchronous fluorescence spectroscopy (SFS) was assessed. Of these nanoparticles, Au-Pd made with an 80:20 Au:Pd ratio displayed excellent catalytic activity for glucose sensing. These nanoparticles could also be homogenized with Nafion to enhance the resonance Rayleigh scattering (RRS) signal. In this study, the structural characterization of noble metal nanoparticles as well as bi- and tri-metallic nanoparticles in addition to their use in non-enzymatic sensing of glucose are reported.

Highlights

Noble metal nanoparticles with surface functionalization by a organotrialkoxysilane (e.g., 3-aminopropyltrimethoxysilane (3-APTMS) and 3-glycidoxypropylytrimethox ysilane (3-GPTMS)) have potential use in catalytic applications [1,2,3,4,5,6,7,8,9,10,11,12,13,14,15]
3-APTMS capped noble metal cations may be converted into monometallic, bimetallic, and trimetallic nanoparticles in the presence of a small organic reducing agent or 3-GPTMS [1,2,3,4,5,6,7,8,9,10,11,12,13]
The Transmission electron microscopy (TEM) images of Ag-Pd bimetallic nanoparticles shown in Figure 1d,e at two microwave processing enables the rapid synthesis of bimetallic nanoparticles and trimetallic nanoparticles with sufficient stability for practical applications; these nanoparticles are shown in the supporting information (Figures S1–S3)

Summary

Introduction

Noble metal nanoparticles with surface functionalization by a organotrialkoxysilane (e.g., 3-aminopropyltrimethoxysilane (3-APTMS) and 3-glycidoxypropylytrimethox ysilane (3-GPTMS)) have potential use in catalytic applications [1,2,3,4,5,6,7,8,9,10,11,12,13,14,15]. The use of 3-APTMS and 3GPTMS to synthesize noble metal nanoparticles has previously been demonstrated [1,2,3,4,5,6,7,8,9,10,11,12,13]. It has been reported that 3-APTMS capped gold ions are converted into nanoparticles in the presence of reducing agents such as 3-GPTMS, cyclohexanone, tetrahydrofuran hydroperoxide, and formaldehyde. The controlled conversion of gold cations to gold nanoparticles within one minute was enabled by the reducing functionality of 3-APTMS, 3-GPTMS, cyclohexanone, and formaldehyde.

Methods

Results

Conclusion