Raman microspectroscopy for non-invasive biochemical analysis of single cells

Abstract

Recent developments in biomedical vibrational spectroscopy now permit the non-invasive imaging of cells and tissues within both the laboratory and clinical settings. The rapid nature and diagnostic potential of both Raman and FTIR (Fourier-transform IR) spectroscopy have resulted in their widespread application to a number of biological fields including fundamental cell biology, medical imaging, tissue engineering and pharmacology. In particular, Raman microspectroscopy shows tremendous promise for the analysis of biological processes within living cells, such as cell cycle dynamics, cell differentiation and cell death. Unlike conventional biological assays, laser-based Raman spectroscopy enables rapid and non-invasive biochemical analysis of cells in the absence of fixatives or labels. The low Raman signal of cell culture buffer/media permits the rapid monitoring of living cells growing under standard cell culture conditions. The Raman spectrum of a cell is a biochemical 'fingerprint', containing molecular-level information about all biopolymers contained within the cell. The high information content of Raman spectra can be used to characterize the distribution of multiple cellular components, and to study the dynamics of subcellular reactions, with excellent spatial resolution. This review highlights recent developments in Raman microspectroscopy, with a focus on non-invasive biochemical analysis of single living cells.

Methods and Applications of Raman Microspectroscopy to Single-Cell Analysis

“…As such, a number of studies have evaluated the potential of Raman spectroscopy as a means to identify and distinguish between different tumorigenic and normal eukaryotic cells. 15,64,65 Moreover, due to their high specificity, Raman-based methods could also be potentially used in the future as a means of label-free cell sorting 66 or to distinguish between different states of differentiation of embryonic stem cells. 67 In early work, Nothinger et al 68 used Raman spectroscopy to discriminate between different bone cell types that are commonly used in tissue engineering of bone.…”

Label‐free biochemical characterization of stem cells using vibrational spectroscopy

“…Raman spectroscopy of biological samples [6,7,[9][10][11][12][13] is based on the inelastic scattering of photons by intrinsic molecular bonds in the sample, which leads to the generation of photons that are shifted in energy from that of the incident photons by an amount equal to the characteristic vibrational energy of the bond. As molecular bonds are probed simultaneously during this process, a Raman spectrum is generated that functions as a 'molecular fingerprint' reflecting the overall biochemical constituents of the sample.…”

Vibrational spectroscopic mapping and imaging of tissues and cells

“…Because of the rapid expansion of biological applications of vibrational spectroscopic mapping and imaging techniques, it is not possible to provide an extensive review of recent research within the space limitations of this article, but an overview of the diversity of applications in medicine and biology, including medical diagnostics, studies of physiological and diseases processes and treatments of diseases and plant biology, can be found in a number of recent reviews (Bailo and Deckert 2008;Bhargava 2007;Boskey and Mendelsohn 2005;Chan et al 2008;Gierlinger and Schwanninger 2007;Levin and Bhargava 2005;Moreira et al 2008;Movasaghi et al 2007;Petibois and Guidi 2008;Petter et al 2009;Srinivasan and Bhargava 2007;Swain and Stevens 2007). As outlined in these reviews and the current review, the increase in the speed of acquisition, sensitivity, discrimination and spatial resolution of the emerging techniques of vibrational spectroscopic microscopies has greatly expanded the horizons of what is possible in terms of an explosion of new knowledge that is being generated.…”