RAMAN LABELS IN LIFE SCIENCES
Raman signals are proportional to concentration and are extremely robust (i.e. no energy transfer between labels such as in fluorescence). It is thus possible to mix a high number of Raman-based labels without affecting their spectral signatures and intensity, making them perfect candidates for simultaneous multicomponent analysis. They can be used in applications such as biomarker identification, protein interaction studies, immunological profiling and vaccine development, among others.
Modifying the Raman label
Modification of the dyes@CNT-COOH labels can easily be achieved through the carbodiimide-mediated amidation. The carboxylic acid group (-COOH) of the label is activated by carbodiimide and will couple with any primary amine (-NH2). On proteins and antibodies, primary amines are present in lysine residues and at the N-terminus of polypeptide chains and can react with the Raman label to form an amide bond. This ecofriendly and biocompatible reaction is done in water and is depticted below.