Core-shell upconverting nanoparticles for applications in nanomedicine

• Grant number: 13/01226-2
• Support Opportunities: Scholarships abroad - Research Internship - Master's degree
• Start date: March 27, 2013
• End date: June 26, 2013
• Field of knowledge: Physical Sciences and Mathematics - Chemistry - Inorganic Chemistry
• Principal Investigator: Sidney José Lima Ribeiro
• Grantee: Karina Nigoghossian
• Supervisor: Denis Boudreau
• Host Institution: Instituto de Química (IQ). Universidade Estadual Paulista (UNESP). Campus de Araraquara. Araraquara , SP, Brazil
• Institution abroad: Université Laval, Canada
• Associated to the scholarship: 11/15759-7 - Cellulose membranes containing nanoparticles for upconversion of energy. Fundamentals and applications., BP.MS

Abstract

The concepts of plasmon-enhanced emission and energy transfer will be applied to the lanthanide-doped yttrium vanadate nanoparticles being studied in the MSc project. Potential applications of these upconversion nanoparticles concern the utilization of the visible light emitted under infrared excitation in order to sensitize some photoactive molecules for photodynamic therapy (PDT). Core-shell nanoparticles (YVO4:Ln@Ag/Au@SiO2) will be prepared, where Ln=Yb/Ho or Yb/Er, where Ag/Au may be a metallic shell or nanoparticles decorating the surface of the oxide nanoparticles, and where SiO2 is a thin silica outer shell to facilitate anchoring of photosensitizer on nanoconstruct. Structural and spectroscopic characterization of the new particles will be explored. Validation of nanoparticle-based photoactivated photosensitizer using spectrophotometric measurements and preliminary PDT studies will be performed with model cancer cells. Nanocomposites made from upconverting nanoparticles and metal colloids will be investigated as possible carriers of singlet oxygen photosensitizer molecules. (AU)