Raman spectroscopy and CARS microscopy of stem cells and their derivatives

Abstract

The characterisation of stem cells is of vital importance to regenerative medicine. Failure to separate out all stem cells from differentiated cells before therapies can result in teratomastumours of multiple cell types. Typically, characterisation is performed in a destructive manner with fluorescent assays. A truly non-invasive method of characterisation would be a major breakthrough in stem cell-based therapies. Raman spectroscopy has revealed that DNA and RNA levels drop when a stem cell differentiates into other cell types, which we link to a change in the relative sizes of the nucleus and cytoplasm. We also used Raman spectroscopy to investigate the biochemistry within an early embryo, or blastocyst, which differs greatly from colonies of embryonic stem cells. Certain cell types that differentiate from stem cells can be identified by directly imaging the biochemistry with CARS microscopy; examples presented are hydroxyapatite -a precursor to bone, and lipids in adipocytes.

Application of Raman spectroscopy for visualizing biochemical changes during peripheral nerve injuryin vitroandin vivo

“…Raman spectroscopy can detect the constituents of objects and has been used to detect abnormalities in biological tissue and cells. [23][24][25][26][27] In the current study, Raman mapping data of peripheral nerve tissue in longitudinal sections of intact sciatic nerve tissue in the range 2800-3000 cm −1 showed three strong peaks at 2853, 2885 and 2940 cm −1 [ Fig. 1(b)].…”

Biomarker-free dielectrophoretic sorting of differentiating myoblast multipotent progenitor cells and their membrane analysis by Raman spectroscopy

“…One of the objectives of this work was to investigate to what extent the chemical composition of the membrane might also influence its specific capacitance value. Raman spectroscopy has previously been used to investigate the chemical changes associated with the differentiation of stem cells, [18][19][20] as well as an on-chip detection method for monitoring the DEP separation of bacteria. 21 In this work, we have used Raman spectroscopy to determine how differences in the molecular composition of the membranes of two cell types of similar size, namely, C2C12 myoblasts and MRC-5 fibroblasts, might correlate with their observed DEP responses and derived C m values.…”

Non-contact, Label-free Monitoring of Cells and Extracellular Matrix using Raman Spectroscopy

“…In this regards, coherent anti-stokes Raman spectroscopy (CARS) is a very interesting technique since it enables faster and more sensitive acquisition of data based on the same vibrational signals utilized in our experiments. 15,16 Other alternative methods including multiphoton-induced autofluorescence and second harmonic generation imaging have been previously proven to be suitable for monitoring biological samples non-or minimal invasively. 17 However, these imaging modalities are associated with very high costs and are limited to autofluorescence-generating molecules.…”