Samuel Achilefu

Stabilization of the Optical Tracer Agent Indocyanine Green Using Noncovalent Interactions

Indocyanine green is a medically useful dye that absorbs and fluoresces in the near infrared and has been sporadically employed clinically as an optical tracer agent for liver function evaluation and cardiac output measurements. The poor stability of this dye in aqueous solution, especially at the high concentrations needed for bolus injection, has been a hindrance in clinical application. However, by using carefully chosen macromolecular additives, the stability of these aqueous dye solutions may be enhanced significantly. Such noncovalent binding between dye and carrier molecules was found to preserve substantially the dye in aqueous solutions for several weeks with no apparent changes in the measured in vivo biological properties.

Bioactive peptide-fluorescent dye conjugates for in vivo tumor imaging

The efficacy of fluorescent optical contrast agents under development for receptor-targeted tumor detection and imaging was assessed in vivo. Tumor targeting of a dye-peptide system is demonstrated and compared to the non-specific retention of the dye alone.