Recent Advances in Plasmonic Nanostructures Applied for Label-free Single-cell Analysis

Cellular heterogeneity presents a major challenge in understanding the relationship between cells of particular genotype and response in disease. In order to characterize the cell-to-cell differences during the biochemical processes, single-cell analysis is necessary. Profiting from the unique localized surface plasmon resonance (LSPR) and Mie scattering, plasmonic nanostructures have revealed stable and adjustable scattering signals, avoiding photobleaching, blinking and autofluorescence phenomenon. These characterizations are propitious to the dynamic trace and biological image of single living cells. In this review, we discuss the recent advances in plasmonic nanostructures applied for label-free detection and monitoring of target cells at single-cell level by using three different techniques, surface-enhanced Raman scattering (SERS), surface-enhanced Infrared absorption spectroscopy (SEIRAS), and dark-field microscopy. Various avenues to design plasmonic probes combining spectra and imaging for single-cell analysis are demonstrated as well. We hope this review can highlight the superiority of plasmonic nanostructures in single cellular analysis, and further motivate the development of label-free cell analysis technique to elucidate cellular diversity and heterogeneity.

Automated summary

Cellular heterogeneity poses a challenge in understanding the relationship between cells of specific genotype and disease response. Single-cell analysis is necessary to characterize cell-to-cell differences during biochemical processes. Plasmonic nanostructures, utilizing unique localized surface plasmon resonance and Mie scattering, provide stable scattering signals for dynamic trace and biological imaging of single living cells, avoiding photobleaching and autofluorescence. Various techniques like surface-enhanced Raman scattering, surface-enhanced Infrared absorption spectroscopy, and dark-field microscopy are used for label-free detection and monitoring of target cells at the single-cell level, demonstrating the potential of plasmonic probes for single-cell analysis.