화학공학소재연구정보센터
Journal of Colloid and Interface Science, Vol.502, 67-76, 2017
Control the drying configuration of suspensions via regulating the surface topologies for surface-enhanced Raman scattering optimization
In this work, the authors present an innovative method to efficiently control the drying configuration of gold nanoparticles (AuNPs) for optimization of surface-enhanced Raman scattering (SEAS) performance with improved sensitivity and re-producibility. Via repeated grafting-casting processes, we have simply regulated the surface topologies of polydimethylsiloxane (PDMS) with average surface roughness ranging from 1.4 nm to 651.3 nm. The assembling configurations of AuNPs after completed evaporation of solvent have been systematically studied on substrates with different roughness degrees. Furthermore, we found that based on the suspended droplet drying method, the inter-gaps among AuNPs can be well optimized on rougher substrate than on flat PDMS. The SERS spectra based on diverse substrates are investigated and compared, with the best available results arising from the roughest PDMS substrate accompanied by suspended drying means. By introducing rhodamine 6G as the probe molecule, such convenient method enables the detection limit down to 10(-1)4 mol/L with linear relationship between the Raman intensity and analyte concentrations within 10(-)8-10(-14) mol/L. The experimental results confirm the superiorities of our proposed method for preparation of SERS substrate, and thus providing a straightforward avenue for future construction of efficient and sensitive platform in fields from environmental monitoring to biological sensors. (C) 2017 Elsevier Inc. All rights reserved.