Tip-enhanced Raman spectroscopic detection of aptamers

TL;DR

This paper demonstrates the use of tip-enhanced Raman spectroscopy (TERS) to detect and analyze single aptamers, providing insights into their chemical composition and conformation for potential applications in biosensing and sequencing.

Contribution

The study introduces TERS for single-molecule aptamer detection, enabling label-free, high-resolution chemical and conformational analysis at the individual molecule level.

Findings

TERS can detect vibrational signals of single aptamers

TERS mapping reveals chemical composition and conformation

Fluctuations in TERS spectra provide insights into molecular dynamics

Abstract

Single molecule detection, sequencing and conformational mapping of aptamers are important for improving medical and biosensing technologies and for better understanding of biological processes at the molecular level. We obtain vibrational signals of single aptamers immobilized on gold substrates using tip-enhanced Raman spectroscopy (TERS). We compare topographic and optical signals and investigate the fluctuations of the position-dependent TERS spectra. TERS mapping provides information about the chemical composition and conformation of aptamers, and paves the way to future single-molecule label-free sequencing.