Spectroscopy and application of confined systems

Confined systems, including nanosystems, are at the forefront of functional material science. The objective of our research is to investigate and design functional molecules and nanostructures with special optical properties for applications in, among others, the biomedical field. As has become clear by now, new scientific challenges are posed to physics and chemistry when the size of a system approaches nanometer scale.

Our research makes use of femtosecond fluorescence upconversion, picosecond time-correlated single-photon-counting, confocal microscopy and other time-resolved and steady-state spectroscopic facilities. These powerful spectroscopic techniques enable us to monitor in real time and over the entire relevant time range the excited state dynamics of noble metals, quantum dots, and discrete emissive centers. We thus can recover the effects of e.g. surface properties and quantum confinement of electrons and/or holes on the photo-excitation and de-excitation dynamics.     

In close collaboration with the Chinese Academy of Sciences, AMC, and LUMC we are developing novel photonic nanoplatforms for biomedical applications. A typical example is the luminescence upconversion nanoplatform where discrete emissive centers - lanthanide ions - are embedded in a nanohost, and efficient IR to Vis/UV photon upconversion is realized. Different structured, biofunctionalized upconversion nanosystems have been developed with high upconversion luminescence and photostability based on the fully spectroscopic study of their photophysics and photochemistry. In-vivo tests have demonstrated that this platform has superior penetration characteristics, and is applicable for the diagnosis and therapy of cancer cells.

 

Contact: Hong Zhang, e-mail: h.zhang@uva.nl
Molecular Photonics (UvA)

Zhang 

Construction of luminescence upconversion nanoplatform for diagnosis and therapy of cancer cells.