Among other applications, Raman labels can be used to target cells. Often, to characterize and identify a cell with certainty, many targeting agents are necessary. The Raman labels offer the possibility to easily mark more than 5 targets unequivocally and simultaneously. Furthermore, their surrounding PEG groups render them non-toxic to many cell lines. The image shown here is a superimposed white light image over the Raman image of bcar@CNT where N9 microglia were incubated with Raman labels, which penetrated the cell with non-specific interactions. The working concentrations did not cause any toxicity to the cells.



In the field of proteomics, protein microarrays and novel detection platforms are gaining popularity because of their potential in high throughput screening (HTS) and much improved sensitivities. Raman labels can be used in protein arrays as novel tags for systems that require very robust or high multiplexing properties. The probes are versatile and can easily be functionalized with different chemical groups such as NH2, COOH, SH, or molecules such as maleimide, biotin, poly(ethylene) glycol (PEG) which makes them ready for bioconjugation. Here, Raman label-PEG-Biot are captured by an array of patterned streptavidin on the surface demonstrating the specificity of the Raman label.



Currently, observing single objects is crucial to understanding certain phenomena at the nanoscale. Detecting and studying single objects is now possible using the intense Raman signal of the Raman labels. Two different probes were deposited on a surface and their hyperspectral response was recorded. Their unique signature allows for unequivocal identification of each probe. Since the Raman signal is not subject to photobleaching or energy transfer, it is possible to identify and quantify overlapping probes.