Polarization microscopy with stellated gold nanoparticles for robust, in-situ monitoring of biomolecules

Abstract

Advances in plasmonic nanoparticle synthesis afford new opportunities for biosensing applications. Here, we apply a combination of a new type of plasmonic nanomaterial - stellated nanoparticles, and polarization-sensitive darkfield microscopy for detecting molecular assemblies and tracking of individual epidermal growth factor receptors within single live cells with high signal-to-background ratio. Depolarization of linear polarized light by stellated nanoparticles is over 15-fold more efficient than similarly-sized spheroidal nanoparticles. This efficient light depolarization allows robust detection of molecules labeled with stellated nanoparticles in cross-polarized imaging where the intrinsic light scattering from cells is significantly reduced. The imaging can be carried out with single molecule sensitivity for essentially unlimited time with no signal degradation.

Comprehensive T-matrix reference database: A 2006–07 update

“…T-matrix calculations of optical resonances in nonspherical particles and particle clusters [4,5,15,18,26,40,48,49,61,72,74,79,[86][87][88][92][93][94]100,154,155,164,169,183,184,197,198,199,211,228,233]. [12,24,25,42,95,113,138,139,189,190,191].…”

Dark-field circular depolarization optical coherence microscopy

“…A method was proposed to efficiently reduce the background by detecting the strong depolarized light originating from asymmetric nanoparticles [18]. Contrast enhancement was demonstrated using this approach experimentally.…”

PEI-conjugated AuNPs as a sensing platform for arsenic (AS-III)

“…The fundamental properties of noble metal nanoparticles depend mainly on their size and surface properties for the objectives that focuses on the control of the morphology. Gold nanoparticles (AuNPs) synthesis and characterisation has grown widely because it is a stable, less toxic and biocompatible technique [1][2][3][4]; recently published examples exhibit the application of nanoparticles in nanotechnology [5], industry [6], medical science [7][8][9], biosensorics [10], genomics [11], immunoassays [12], immune response enhancement [13], targeted drug delivery [14], cancer cell photothermolysis [15] and optical imaging of biological cells [16]. Currently, nanoparticles are attractive due to their easy synthesis, modification as well as their size, shape and distribution [17,18].…”