Ulrich Krull

Luminescence from nanoparticles (NPs) can be used to interrogate selective interactions at the surface of the nanoparticles by means of resonance energy transfer to a fluorescent label that serves to transduce a binding interaction. Selectivity can be established using immobilized biomolecules on nanoparticles for interaction with proteins, peptides and nucleic acid sequences. Multiplexed solid-phase bioassays on paper-based platforms would be useful technology for rapid detection of markers for pathogens and genetically-based disease. Samples can be manipulated using microfluidics for extraction, concentrating and delivery to the detection system. Our exploration of a combination of various approaches to achieve signal enhancement have allowed use of cell phone cameras as spectrally-selective detectors. We are also exploring the use of upconversion for the photo-controlled intracellular release of drugs. In this approach the NP acts as a platform to cage the therapeutic compound, and to convert near-infrared excitation light to UV-vis emission for photolytic cleavage. The therapeutic compound can be released while the NP concurrently provides the capability to bioassay molecular markers in the sample.