Krull, Ulrich J.
Nanotechnology and fluidics for bioassays and theranostics
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.
CHM414H5 (undergraduate); CHM1103H, CHM1105H, CHM1152H, CHM1157H (graduate)
Uddayasankar, U. and U.J. Krull. 2015. Energy Transfer Assays Using Quantum Dot-Gold Nanoparticle Complexes: Optimizing Oligonucleotide Assay Configuration Using Monovalently Conjugated Quantum Dots, Langmuir, 31: 8194-8204.
Doughan, S., U. Uddayasankar and U.J. Krull. 2015. A paper-based resonance energy transfer nucleic acid hybridization assay using upconversion nanoparticles as donors and quantum dots as acceptors, Analytica Chimica Acta, 878: 1-8.
Noor, M.O. and U.J. Krull. 2014. Camera-based ratiometric fluorescence transduction of nucleic acid hybridization with reagentless signal amplification on a paper-based platform using immobilized quantum dots as donors, Analytical Chemistry, 86: 10331-10339.
Fedoryshin, L.L., A.J. Tavares, E. Petryayeva, S. Doughan and U.J. Krull. 2014. Near-infrared triggered anticancer drug release from upconverting nanoparticles, ACS Applied Materials and Interfaces, 6: 13600-13606.
Zhou, F. and U.J. Krull. 2014. Spectrally matched duplexed nucleic acid bioassay using two-colors from a single form of upconversion nanoparticle, Analytical Chemistry, 86:10932-10939.
Uddayasankar, U. and U.J. Krull. 2013. Analytical performance of molecular beacons on surface immobilized gold nanoparticles of varying size and density, Analytica Chimica Acta, 803: 113-122.
Noor, M.O. and U.J. Krull. 2013. Paper-based Solid-Phase Multiplexed Nucleic Acid Hybridization Assay With Tunable Dynamic Range Using Immobilized Quantum Dots as Donors in Fluorescence Resonance Energy Transfer, Analytical Chemistry, 85: 7502-7511.
Tavares, A.J., M.O. Noor, C.H. Vannoy, W.R. Algar and U.J. Krull. 2012. On-Chip Transduction of Nucleic Acid Hybridization Using Spatial Profiles of Immobilized Quantum Dots and Fluorescence Resonance Energy Transfer, Analytical Chemistry, 84: 312-319.
Chong, L., C.H. Vannoy, M.O. Noor and U.J. Krull. 2012. Intracellular nucleic acid interactions facilitated by quantum dots: Conceptualizing theranostics, Therapeutic Delivery, 3: 479-499.
Chen, L., W.R. Algar, A.J. Tavares and U.J. Krull. 2011. Toward a solid-phase nucleic acid hybridization assay within microfluidic channels using immobilized quantum dots as donors in fluorescence resonance energy transfer. Analytical and Bioanalytical Chemistry, 399: 133-141.
Algar, W.R. and U.J. Krull. 2011. Characterization of the adsorption of oligonucleotides on mercaptopropionic acid-coated CdSe/ZnS quantum dots using Fluorescence Resonance Energy Transfer. Journal of Colloid and Interface Science, 359: 148-154.