Approved indocyanine green

Organic dyes like fluorescein and TRITC and the majority of NIR fluorophores suffer from poor photostability [77]. In addition, many NIR dyes, such as clinically approved indocyanine green (ICG) reveal poor thermal stability in aqueous solution [78]. Moreover, the presence of ozone can result in dye decomposition as observed for Cy5 [79]. In the last years, many organic dyes like the Alexa dyes have been... 

A prominent representative example of a near-infrared absorbing cyanine dye is Indocyanine Green (ICG). This compound was first synthesized in the fifties [35] and was clinically approved as a diagnostic drug for the assessment of hepatic function and cardiac output, for which ICG exhibits favourable phar-... 

In our work we utilized the long-wavelength dye indocyanine green (ICG) (Figure 24), which is widely used in a variety of in vivo medical applications. ICG is not toxic and is approved by the U.S. Food and Drug Administration for use in humans, typically by injection. ICG displays a low quantum yield in solution, 0.016, and a somewhat higher quantum yield when bound to serum albumin. Albumin adsorbs to form a monolayer and ICG spontaneously binds to albumin. ICG is chemically and photochemically unstable, and thus provided us with an ideal opportunity to test deposited silver for both metal-enhanced emission and increased ICG photochemical stability. 

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