Highly Sensitive, Engineered Magnetic Nanosensors to Investigate the Ambiguous Activity of Zika Virus and Binding Receptors.

The aim of this research is twofold: 1) to shed light on zika's binding and entry mechanism while 2) demonstrating the effectiveness of our magnetic relaxation platform to achieve this goal. Magnetic relaxation-sensitive nanoparticles (MRNPs) are used in a novel fashion to analyze binding interactions between the zika envelope protein (ZENV) and proposed host cell receptors: AXL, HSP70, and TIM-1. Computational analysis is also utilized to examine these binding interactions for the first time. In addition, the role of crizotinib as a potential binding inhibitor is demonstrated and the possibility of ligand-independent phosphatidylserine-mediated binding is explored. Our findings suggest that while the extracellular domain of AXL has the highest affinity for ZENV; HSP70, TIM-1, and phosphatidylserine might also play active roles in zika tropism, which offers a potential explanation for the variety of zika-associated symptoms. This is, to our knowledge, the first time that MRNPs have been used to examine and quantify host-zika interactions. Our magnetic relaxation platform allows for timely and sensitive analysis of these intricate binding relationships, and it is easily customizable for further examination of additional host-pathogen interactions.

Novel magnetic relaxation nanosensors: an unparalleled "spin" on influenza diagnosis.

Rapid detection and diagnosis of pathogenic strains of influenza is necessary for expedited treatment and quicker resolutions to the ever-rising flu pandemics. Considering this, we propose the development of novel magnetic relaxation nanosensors (MRnS) for the rapid detection of influenza through targeted binding with hemagglutinin. 2,6- and 2,3-sialic acid ligands and entry blocker peptides are conjugated to iron oxide nanoparticles to create functional MRnS. Positive detection of various hemagglutinin variants (H1 and H5) is possible with protein concentrations as little as 1.0 nM. Most importantly, detection using functional MRnS is achieved within minutes and differentiates between influenza subtypes. This specificity allows mixtures of MRnS to screen for multiple pathogens at once, discarding the need to conduct multiple individual tests. Current methods used to diagnose influenza, such as RT-PCR and viral culturing, while largely effective, are complex, time-consuming and costly. As well, they are not as sensitive or specific, and have been known to produce false-positive results. In contrast to these methods, targeted MRnS are robust, point-of-care diagnostic tools featuring simple, rapid and low-cost procedures. These qualities, as well as high sensitivity and specificity, and low turnaround times, make a strong case for the diagnostic application of MRnS in clinical settings.