Singlet oxygen generation from water-soluble quantum dot-organic dye nanocomposites

CHED 60

Lixin Shi, lshi@cslanet.calstatela.edu, Jacquie Malette, sweetie1032000@yahoo.com, Aracelle B Dasalla, asgamboa@gmail.com, Billy Hernandez, billyhernadez@hotmail.com, and Matthias Selke, mselke@calstatela.edu. Department of Chemistry and Biochemistry, California State University, Los Angeles, 5151 State University Drive, Los Angeles, CA 90032
Water-soluble quantum dot - organic dye nanocomposites have been prepared via electrostatic interaction. We used CdTe quantum dots with variable diameters. The photophysical properties of the nanocomposites have been investigated. The fluorescence of the parent CdTe quantum dot is largely suppressed. Instead, indirect excitation of the TSPP moiety leads to production of singlet oxygen. The nanocomposites are sufficiently photostable for biological applications. Photophysical properties of the nanocomposites have been studied as a function of QDs diameter. Such nanocomposites may be used as model systems for in vivo imaging and photodynamic therapy.