Raman spectroscopy – a potential platform for the rapid measurement of carbon nanotube-induced cytotoxicity

Section: Introductionmentioning

confidence: 99%

Raman spectroscopic mapping for the analysis of solar radiation induced skin damage

Ali¹,

Bonnier²,

Ptasiński³

et al. 2013

“…[23][24][25][26][27][28] In confocal microscopic mode, the spatial resolution is of the order of ≤1 µm, depending on source wavelength, providing access to the subcellular organisation of the cells. 29,30 Thus, Raman spectroscopy potentially offers a label free probe of nanoparticles within cells, which can potentially analyse their local environment, and ultimately changes in the cellular metabolism which can be correlated with cytotoxic responses 31 , oxidative stress, or inflammation. Kneipp et al.…”

Section: Introductionmentioning

confidence: 99%

Identifying and localizing intracellular nanoparticles using Raman spectroscopy

Dorney¹,

Bonnier²,

Garcia³

et al. 2012

Self Cite

108

Raman microscopy is employed to spectroscopically image biological cells previously exposed to fluorescently labelled polystyrene nanoparticles and, in combination with Kmeans clustering and Principal Component Analysis (PCA), is demonstrated to be capable of localising the nanoparticles and identifying the subcellular environment based on the molecular spectroscopic signatures. The neutral nanoparticles of 50 nm or 100 nm, as characterised by dynamic light scattering, are shown to be non-toxic to a human lung adenocarcinoma cell-line (A549), according to a range of cytotoxicity assays including Neutral Red, Alamar Blue, Coomassie Blue and (3-(4,5-Dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT). Confocal fluorescence microscopy identifies intracellular fluorescence due to the nanoparticle exposure, but the fluorescence distribution is spatially diffuse, potentially due to detachment of the dye from the nanoparticles, and the technique fails to unambiguously identify the distribution of the nanoparticles within the cells. Raman spectroscopic mapping of the cells in combination with K-means cluster analysis is used to clearly identify and localise the polystyrene nanoparticles in exposed cells, based on their characteristic spectroscopic signatures. PCA identifies the local environment as rich in lipidic signatures which are associated with localisation of the nanoparticles in the endoplasmic reticulum. The importance of optimised cell growth conditions and fixation processes is highlighted. The preliminary study demonstrates the potential of the technique to unambiguously identify and locate nonfluorescent nanoparticles in cells and to probe not only the local environment but also changes to the cell metabolism which may be associated with cytotoxic responses.

“…16,[18][19][20] There has been a wide range of studies to date demonstrating the potential of Raman micro spectroscopy to map live and fixed cells with subcellular resolution, [21][22][23][24][25] profile the distribution of anticancer agents [26][27][28][29][30] and nanoparticles in cells 16,31,32 and monitor subcellular processes 33 and toxicological responses. [34][35][36][37] Fundamental to the development of applications of Raman micro spectroscopy for disease diagnostics as well as analysis of cytological processes is an understanding of the variability of the spectral signatures across the subcellular environment, their potential for differentiation of cell phenotype or diseased state, and their sensitivity to external perturbation, such as viral infection, radiation damage, or chemical stress due to, for example, toxic or chemotherapeutic agents. It is clear that the signatures for the cytoplasm, nucleus and nucleoli are distinct and differentiable, 38 but it is not clear which region has the best diagnostic potential or sensitivity to external insult.…”

Section: Introductionmentioning

confidence: 99%

Cellular discrimination using in vitro Raman micro spectroscopy: the role of the nucleolus

Farhane

Bonnier

Casey

et al. 2015