Thiol-reactive, near-infrared dye Cyanine7.5 for labeling of protein SH groups, an analog of Cy7.5® maleimide.
Most proteins contain sulfhydryl groups which can be selectively labeled with maleimides. With this reagent, these proteins can be converted to near-infrared (NIR) fluorescent conjugates. After it, the conjugates can be used in non-invasive live organism imaging to study distribution of the protein in tissues and organs.
Cy7.5 maleimide is a CY dye. CY, short for Cyanine, is a compound consisting of two nitrogen atoms connected by an odd number of methyl units. Cyanine compounds have the characteristics of long wavelength, adjustable absorption and emission, high extinction coefficient, good water solubility and relatively simple synthesis[1]. CY dyes are of en used for the labeling of proteins, antibodies and small molecular compounds. For the labeling of protein antibodies, the combination can be completed through a simple mixing reaction. Below, we introduce the labeling method of protein antibody labeling, which has certain reference significance[2].
[1] Yongzhi Men, et al. Biodegradable Zwitterionic Nanogels with Long Circulation for Antitumor Drug Delivery. ACS Appl Mater Interfaces. 2018 Jul 18;10(28):23509-23521. DOI:
10.1021/acsami.8b03943[2] Ptaszek M. Rational design of fluorophores for in vivo applications. Prog Mol Biol Transl Sci. 2013;113:59-108. DOI:
10.1016/B978-0-12-386932-6.00003-X[3] Shindy, H. A. (2017). Fundamentals in the chemistry of cyanine dyes: A review. Dyes and Pigments, 145, 505–513. doi:10.1016/j.dyepig.2017.06.029
