ICG exhibits an absorption maximum in the near infrared region (NIR) at ca. 800 nm with a slight absorption in the visible range, which results in low auto-fluorescence. The emission maximum is at 810 nm. This absorption/emission profile allows for tissue-penetrating excitation without causing tissue damage. Consequently, ICG has found use in fields as diverse as angiography, detection of solid tumors and fluorescence image-guided surgery.

Absorption and emission spectra of Indocyanine Green (spectrum courtesy of AAT Bioquest, Inc.).

Iris Biotech offers a series of ICG dyes equipped with different popular functional groups for conjugation, such as maleimide, 2-Cyanobenzothiazole (CBT), NHS ester, as well as various clickable moieties.

Functional groups available for conjugation of Indocyanine Green.

→ Do you require a various functional group for conjugation? Inquire with our Custom Synthesis Service.

References:

• Development of PLGA-lipid nanoparticles with covalently conjugated indocyanine green as a versatile nanoplatform for tumor-targeted imaging and drug delivery; Y. Xin, T. Liu and C. Yang; International journal of nanomedicine 2016; 11: 5807-5821. doi:10.2147/ijn.s119999
• Clinical applications of indocyanine green (ICG) enhanced fluorescence in laparoscopic surgery; L. Boni, G. David, A. Mangano, G. Dionigi, S. Rausei, S. Spampatti, E. Cassinotti and A. Fingerhut; Surgical Endoscopy 2015; 29: 2046-2055. doi:10.1007/s00464-014-3895-x
• Optimal back-extrapolation method for estimating plasma volume in humans using the indocyanine green dilution method; D. Polidori and C. Rowley; Theoretical Biology & Medical Modelling 2014; 11: 33-33. doi:10.1186/1742-4682-11-33
• A Review of Indocyanine Green Fluorescent Imaging in Surgery; J. T. Alander, I. Kaartinen, A. Laakso, T. Pätilä, T. Spillmann, V. V. Tuchin, M. Venermo and P. Välisuo; International Journal of Biomedical Imaging 2012; 2012: 940585. doi:10.1155/2012/940585
• Near-Infrared Fluorescence Imaging in Humans with Indocyanine Green: A Review and Update; M. V. Marshall, J. C. Rasmussen, I. C. Tan, M. B. Aldrich, K. E. Adams, X. Wang, C. E. Fife, E. A. Maus, L. A. Smith and E. M. Sevick-Muraca; Open surgical oncology journal (Online) 2010; 2: 12-25. doi:10.2174/1876504101002010012
• Application of a biodegradable macromolecular contrast agent in dynamic contrast enhanced MRI for assessing the efficacy of indocyanine green enhanced photothermal cancer therapy; Y. Feng, L. Emerson, E.-K. Jeong, D. L. Parker and Z.-R. Lu; Journal of magnetic resonance imaging : JMRI 2009; 30: 401-406. doi:10.1002/jmri.21838