Raman Mapping: Emerging Applications

Abstract

Raman mapping is a noninvasive, label-free technique with high chemical speciicity and high potential to become a leading method in biological and biomedical applications. As opposed to Raman spectroscopy, which provides discrete chemical information at distinct positions within the sample, Raman mapping provides chemical information coupled with spatial information. The laser spot scans the investigated sample area with a preset step size and acquires Raman spectra pixel by pixel. The Raman spectra are then discriminated from each other by chemometric analysis, and the end result is a false color map, an image of the sample that contains highly precise structural and chemical information. Raman imaging has been successfully used for label-free investigations at cellular and subcellular level. Cell compartments, cell responses to drugs and diferent stages of the cell cycle from the stem cell to the completely diferentiated cell were successfully distinguished. This technique is also able to diferentiate between healthy and cancer cells, indicating great potential for replacing conventional cancer detection tools with Raman detection in the future.

Recent advances in surface‑enhanced Raman spectroscopy based liquid biopsy for colorectal cancer (Review)

“…Raman spectroscopy and SERS-basic principles. Raman spectroscopy is in principle a vibrational spectroscopic method, in which molecular structural information is gained by analyzing the inelastic scattering of photons (15,16). However, the technique suffers from low sensitivity, as only one in approximately 10 million photons is scattered inelastically, carrying thus Raman information.…”

Principles and Applications of Vibrational Spectroscopic Imaging in Plant Science: A Review

“…Algae serve as highly suitable model plant organisms and are important part of the ecosystem. Therefore, they attract considerable attention in plant science ( Coman and Leopold, 2017 ). Similar to various other algae, upon light irradiation Chlorella species ( C. protothecoides and C. vulgaris ) produce and accumulate large amount of carotenoids within their cells.…”

“…Noteworthy, alongside the major constituents, Raman imaging is capable of elucidating the distribution of other class of compounds within plant’s body ( Coman and Leopold, 2017 ). Polyacetylenes can be monitored at ca.…”

Recent Progress of SERS Nanoprobe for pH Detecting and Its Application in Biological Imaging

“…It has the characteristics of high-speed, noninvasive, label-free and extremely high resolution imaging. During Raman imaging, we scanned the measured area of the sample with a laser with a preset wavelength and obtained the Raman spectrum of each set point and then the Raman image with highly precise structural and chemical information is obtained from the chemometric analyzed Raman spectra [12]. In general, particles with large size and tip morphology (such as nanoflowers, nanostars, and so on) or in an aggregated state will have stronger Raman signals [13,14].…”