Development of Quantum Dots as Biosensing Probes

Appendix E Movie 1: Nanoassembly transport around a microdisc. Control is demonstrated by magnetic trapping of the nanoassembly. A reverse motion around the disk is shown from 11-16 seconds, and then the particle continues its clockwise trajectory. After 33 seconds the nanoassembly is released from the microdisc. ; Appendix E Movie 2: Nanoassembly transport on nanowires via vertex-to-vertex hopping. ; Appendix E Movie 3: Simultaneous magnetic transport of red protein (avidin) and green DNA (p53 ssDNA) nanoassemblies via vertex to vertex hopping on magnetic nanowire arrays. ; Appendix E Movie 4: Red, magnetic protein nanoassemblies (i.e., avidin as the molecular target, containing SPIONs) are trapped and transported from vertex-to-vertex, whereas green, non-magnetic DNA nanoassemblies (p53 ssDNA as the molecular target, containing no SPIONs) are not trapped and display motion resulting from Brownian motion or liquid flow. ; Appendix E Movie 5: Following addition of DNA-targeting SPION micelles, green, magnetic DNA nanoassemblies (p53 ssDNA as the molecular target, containing QDs and SPIONs) are transported, showing rapid conjugation of SPIONs to green micelle structures. ; Appendix E Movies 1 - 5 reproduced from: K. D. Mahajan, G. Ruan, G. Vieira, T. Porter, J. J. Chalmers, R. Sooryakumar and J. O. Winter, J. Mater. Chem. B, 2020, Advance Article, https://doi.org/10.1039/C9TB02481F - Reproduced by permission of The Royal Society of Chemistry. ; Quantum dots (QDs) are semiconductor nanoparticles that exhibit size-dependent optical properties. Compared to other common fluorophores such as dyes and fluorescent proteins, QDs possess higher photon emission rates. Additionally, they have broad absorption spectra and narrow, size-tunable emission spectra that enable color multiplexing. Their resistance to photobleaching also makes them suitable for tracking over long periods of time. Thus, QDs possess numerous properties that make them attractive for biosensing applications. However, several concerns must be addressed ...