@article {Pinals761296, author = {Rebecca L. Pinals and Darwin Yang and Alison Lui and Wendy Cao and Markita P. Landry}, title = {Corona exchange dynamics on carbon nanotubes by multiplexed fluorescence monitoring}, elocation-id = {761296}, year = {2019}, doi = {10.1101/761296}, publisher = {Cold Spring Harbor Laboratory}, abstract = {Noncovalent adsorption of DNA on nanoparticles has led to their widespread implementation as gene delivery tools and optical probes. Yet, the behavior and stability of DNA-nanoparticle complexes once applied in biomolecule-rich, in vivo environments remains unpredictable, whereby biocompatibility testing usually occurs in serum. Here, we demonstrate time-resolved measurements of exchange dynamics between solution-phase and adsorbed corona-phase DNA and protein biomolecules on single-walled carbon nanotubes (SWCNTs). We capture real-time binding of fluorophore-labeled biomolecules, utilizing the SWCNT surface as a fluorescence quencher, and apply this corona exchange assay to study protein corona dynamics on ssDNA-SWCNT-based dopamine sensors. We study exchange of two blood proteins, albumin and fibrinogen, adsorbing to and competitively displacing (GT)6 vs. (GT)15 ssDNA from ssDNA-SWCNTs. We find that (GT)15 binds to SWCNTs with a higher affinity than (GT)6 and that fibrinogen interacts with ssDNA-SWCNTs more strongly than albumin. Albumin and fibrinogen cause a 52.2\% and 78.2\% attenuation of the dopamine nanosensor response, coinciding with 0.5\% and 3.7\% desorption of (GT)6, respectively. Concurrently, the total surface-adsorbed fibrinogen mass is 168\% greater than that of albumin. Binding profiles are fit to a competitive surface exchange model which recapitulates the experimental observation that fibrinogen has a higher affinity for SWCNTs than albumin, with a fibrinogen on-rate constant 1.61-fold greater and an off-rate constant 0.563-fold smaller than that of albumin. Our methodology presents a generic route to assess real-time corona exchange on nanoparticles in solution phase, and more broadly motivates testing of nanoparticle-based technologies in blood plasma rather than the more ubiquitously-tested serum conditions.}, URL = {https://www.biorxiv.org/content/early/2019/09/10/761296}, eprint = {https://www.biorxiv.org/content/early/2019/09/10/761296.full.pdf}, journal = {bioRxiv} }