Nanostructure-assisted optical tweezers for microspectroscopic polymer analysis

Abstract

Raman/fluorescence microspectroscopic analysis of individual polymer chains and nanobeads dissolved in solution will become a powerful analytical method to study their molecular structure and characteristics. With this motivation, we focused on the use of Raman microspectroscopy for optically trapped soft matter. A tightly focused near-infrared laser beam formed a microassembly of thermoresponsive polymer chains such as poly(N-isopropylacrylamide) due to a local photothermal effect and optical force. By using this method, we developed a technique for determining the polymer concentration in a polymer microassembly. Furthermore, we demonstrated a molecular condensation and detection technique based on microassembly on plasmonic nanostructures. For this molecular condensation and detection process, localized surface plasmons play an essential role in the optical force enhancement and local temperature increase around the plasmonic nanostructures. Finally, aiming toward novel manipulation methods of smaller soft nanomaterials, nanostructured semiconductor-assisted (NASSCA) optical tweezers are introduced. In this paper, we reviewed the optical manipulation methods of polymer chains and nanobeads and their applications in analytical chemistry.

Effect of surfactant compounding on emulsion stability and acid-base resistance using optical tweezers

“…Compared to standard techniques, this method can capture individual yeast cells at signi cantly lower power levels. Shoji et al [30] focused on nanostructure-assisted optical tweezers for microspectral polymer analysis, demonstrating the potential of Raman/ uorescence microspectroscopy for the study of individual polymer chains and nanoparticles. Torres-Saucedo et al [31] propose a method to induce local shear stress on a cancer nodal model using optical tweezers, demonstrating the versatility of optical tweezers in studying biological systems.…”