A Novel Method for Detection of Phosphorylation in Single Cells by Surface Enhanced Raman Scattering (SERS) using Composite Organic-Inorganic Nanoparticles (COINs)
Figure 3
Specificity of COIN based Raman spectroscopy for detection of Surface antigens.
a) Expression of ICAM (CD54) and absence of CD8 expression on U937 cells was determined by FLOW cytometry (left). Expression of CD54 on U937-expressing cells and H82-non-expressing cells was determined by FLOW cytometry (center). Expression of CD8 in a subset of human PBMCs was compared to non-expressing U937 and H82, determined by FLOW cytometry (right). b) Antigen specific detection of CD54 using COIN. Raman intensity of spectra from cells stained with αCD54-BFU and αCD8-BFU COINs (left). The spectra are representative for five independent experiments. Quantitation of Raman peak height is represented as histograms of five independent experiments performed in duplicates (right). The αCD54-BFU COINs specifically detected CD54 on U937 cells **p<0.01. c) Cell-specific detection of CD54 surface antigen using COIN. Raman spectra from CD54 expressing U937 cells and non-expressing H82 cells stained with αCD54-BFU COIN (left). Quantitation of Raman peak height is represented as histograms (right). The αCD54-BFU COINs specifically detected CD54 on U937 cells **p<0.01. d) SEM images of U937 cells stained with αCD54-BFU (left) and BFU (right) COINs. e) Characterization of a cell population in primary blood cells using COIN. Raman spectra of human PBMC, H82 and U937 cells stained with αCD8-BFU COIN (left). Quantitation of Raman peak height is represented as histograms (right). The αCD8-BFU COINs specifically detected CD8 on hPBMCs **p<0.01.