Focused ion beam microscope as an analytical tool for nanoscale characterization of gradient-formulated polymeric sensor materials

Abstract

In this study, we are demonstrating localized nano-scale analysis of sensor materials which are developed using combinatorial gradient approach. Our technique based on Focused Ion Beam cross-sectioning at specific locations affords establishing metal nano-particles concentrations at best-performing area(s) of gradient-formulated polymer samples. We have achieved threedimensional characterization/mapping of nano-fillers (30-100 nm metal particles) in composite thin films on variety of substrates.

Combinatorial and High-Throughput Development of Sensing Materials: The First 10 Years

“…The nanoparticle LSPR approach was established for biosensing with the pioneering work of Mirkin and co-workers, who demonstrated the selective colorimetric detection of polynucleotides with the use of the distance-dependent optical properties of Au nanoparticles . The approach that utilizes the aggregation-induced, red-to-blue color change associated with Au nanoparticles is attractive for myriad applications ranging from screening of combinatorial libraries of DNA-binding molecules with DNA-functionalized Au nanoparticles to chemical sensing. − Analysis of hybridization events in combinatorial DNA arrays using oligonucleotide-modified and Ag-stained Au nanoparticle probes on a conventional flatbed scanner had a detection sensitivity exceeding that of the analogous fluorophore system by 2 orders of magnitude …”

“…To visualize and quantify the gradient distribution of plasmonic nanoparticles in sensing films, Dovidenko, Potyrailo, and co-workers developed an approach based on focused ion beam (FIB) cross-sectioning of a sensing film followed by the 3-D reconstruction of the spatial distribution of nanoparticles (see Figure ) . These new methods for controlled organization of nanoparticles within polymer matrices 283-286 coupled with the visualization and quantitation of nanoparticles in the polymer 280 are important for the development of chemical and biological sensors with the tailored dynamic range of sensor response.…”

“…Data sets of ∼25 nm thick FIB serial slices are sectioned normal to Z direction in the picture (lateral dimensions, X = Y = 3.4 μm). Reprinted with permission from ref . Copyright 2006 Materials Research Society. …”