Studies on fluorescence resonance energy transfer between dyes and water-soluble quantum dots.

In this work, donor-acceptor complexes were formed based on antibody-antigen interactions. Immunoglobulin antigen (mouse-IgG) was effectively conjugated to mercaptopropyl acid-modified CdTe quantum dot synthesized in aqueous solution via electrostatic interaction, while organic dyes-tetramethylrhodamine isothiocyanate (TRITC) were attached to the corresponding antibody (anti-mouse IgG). The mutual affinity of the antigen and antibody brought the CdTe quantum dot and TRITC sufficiently close together to allow the resonance dipole-dipole coupling required for fluorescence resonance energy transfer to occur. The formation of immunocomplexes resulted in fluorescence resonance energy transfer from the CdTe quantum dot donors to the TRITC acceptors. Copyright 2005 John Wiley & Sons, Ltd.