pathogens, toxins, sensing, iron oxide, magnetic nanoparticles
The use of nanoparticles and NMR detection technologies has lead to significant improvements in sensitivity. Nanoparticles have many useful optical and electronic properties derived from their small size. When coupled to affinity ligands, these materials have been utilized as chemical sensors such as fluorescent quantum dots and carbon nanotubes to detect DNA and to create immunoassays for the detection of bacteria and toxins However, these methods are limited in that they cannot be analyzed in turbid media, they require purification of the target molecule prior to analysis, and utilize non-portable instrumentation. One alternative is the use of non-toxic iron oxide based magnetic nanoparticles for highly sensitive detention of molecular targets. In this case, the classical label is replaced by a superparamagnetic nanoparticle, which can be detected magnetically. This investigator has developed an innovative detection approach that relies on the effect that iron oxide-based nanoparticles have on the NMR signal of neighboring water molecules, and utilize non-portable instrumentation.This NMR-based detection approach requires no separation; it is robust to interferences and has been performed in whole blood, lipid emulsion, and tissue culture media. The potential of the technique to detect other toxins and pathogens in clinical and environmental samples is being pursued.