SERS Quantification and Characterization of Proteins and Other Biomolecules

Abstract

Changes in protein expression levels and protein structure may indicate genomic mutations and may be related to some diseases. Therefore, the precise quantification and characterization of proteins can be used for disease diagnosis. Compared with several other alternative methods, surface-enhanced Raman scattering (SERS) spectroscopy is regarded as an excellent choice for the quantification and structural characterization of proteins. Herein, we review the main advance of using plasmonic nanostructures as SERS sensing platform for this purpose. Three design approaches, including direct SERS, indirect SERS, and SERS-encoded nanoparticles, are discussed in the direction of developing new precise approaches of quantification and characterization of proteins. While this Review is focused on proteins, in order to highlight concepts of SERS-based sensors also detection of other biomolecules will be discussed.

Multiplex SERS Detection of Metabolic Alterations in Tumor Extracellular Media

“…[ 14 ] Therefore, SERS has emerged as a promising method for the detection and characterization of biological molecules in solution and within cells for cancer diagnosis. [ 15,16 ] On the one hand, on account of the complexity related to the interpretation of spectra obtained in biological media, much work has focused on comparing spectra of samples from healthy and cancer patients. [ 17–20 ] On the other hand, efforts have been made to computationally decipher the contributions of a number of analytes to the final SERS spectra.…”

Spot‐on SERS Detection of Biomolecules with Laser‐Patterned Dot Arrays of Assembled Silver Nanowires

“…This value is well below that of a standard SERS probe such as rhodamine 6G, in both resonant (10 −25 cm 2 ) and nonresonant (10 −27 cm 2 ) conditions . Moreover, biomolecules in their own biological environments are found in highly diluted (micromolar and below) concentration . Thus, in order to capture enough SERS signal from the biomolecule content of a biological sample, increasing the local molecular density at SERS‐sensitive sites or using structures with sharp nanoscaled protrusions or tips featuring intense E‐fields are amongst the most convenient approaches.…”

“…[28] Moreover, biomolecules in their own biological environments are found in highly diluted (micromolar and below) concentration. [29] Thus, in order to capture enough SERS signal from the biomolecule content of a biological sample, increasing the local molecular density at SERS-sensitive sites [30,31] or using structures with sharp nanoscaled protrusions or tips featuring intense E-fields [32,33] are amongst the most convenient approaches. Here, we tried to capitalize on both these aspects aimed at assuring as well the fundamental prerequisites of SERS substrates for widespread use.…”

Nanoscale Discrimination between Toxic and Nontoxic Protein Misfolded Oligomers with Tip‐Enhanced Raman Spectroscopy

“…As a result, identification of trace amounts of molecular species becomes feasible. This has recently inspired a number of studies aimed at the quantification and structural characterization of physiological quantities of proteins and other biomolecules …”

“…This has recently inspired a number of studies aimed at the quantification and structural characterization of physiological quantities of proteins and other biomolecules. [10][11][12][13][14][15][16][17] In tip-enhanced Raman spectroscopy (TERS), the high sensitivity of SERS is combined with the nanoscale spatial resolution of scanning probe microscopy (SPM). [18][19][20][21][22] TERS exploits the high-localized EM field enhancement on a sharp metallized tip to achieve compositional and structural information from the surface of nanosized samples.…”