ICG is a fluorophore, and it has been utilized for over a half-century in human clinical use. Conventional activated ICG dye, ICG-Sulfo-OSu has been utilized in in vivo imaging research as antibody conjugates. However, due to the hydrophobic characteristics which unspecific bound to antibodies are seen (results in higher background). As a next generation of ICG dye, ICG with short PEG linkers such as ICG-PEG4-Sulfo-OSu and ICG-PEG8-SUlfo-OSu are synthesized to increase the hydrophilicity character of the dye. The PEGylated ICGs shows higher covalent binding to antibodies, significantly reducing unspecific binding. Therefore, ICG with short PEG linkers is found to be more suitable compound for in vivo imaging research.
Advantage of PEGylated ICG
PEGylated ICG is more suitable for in vivo imaging due to low background.
PEGylated ICG Derivatives (ICG-EGn-Sulfo-OSu)
Non-PEGylated ICG (ICG-Sulfo-Osu)
<In vivo Background>
<Performance of PEGylated ICG>
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