Isolating Nanoparticles from Blood
Nanoparticles have been enjoying much significance in biomedical applications, particularly in drug delivery. However, one nuisance that researchers face when working with nanoparticles is isolating them from blood, especially the plasma.
One method of isolating nanoparticles involves diluting the plasma, adding a high concentration sugar solution, and spinning it in a centrifuge. Another involves attaching a targeting agent to the surface of the nanoparticles. However, these methods either alter the normal behavior of the nanoparticles are, even worse, don't work with some nanoparticle types.
Fortunately, these troubles may be solved, thanks to a breakthrough development made by researchers from the University of California, San Diego. Ultimately, the team created an oscillating electric field was used to easily and quickly isolate drug-delivery nanoparticles from blood.
Using an Electric Field
An electric chip the size of a dime was used to isolate the drug-delivery nanoparticles. The chip contains hundreds of tiny electrodes that generate a rapidly oscillating electric field (15 kHz) that selectively pulls the nanoparticles out of the plasma.
In the study, researchers inserted a drop of plasma with nanoparticles into the electric chip and demonstrated nanoparticle recovery within 7 minutes. It even worked on different types of drug-delivery nanoparticles that are typically studied in various labs. The chip can also work in the high salt concentrations of blood plasma.
As the oscillating electric field is applied, positive and negative charges inside the nanoparticles reorient themselves at a different rate than the charges in the plasma. This difference generates an attractive force between the nanoparticles and the electrodes. As the oscillation continues, the nanoparticles are pulled towards the electrodes, leaving the rest of the plasma behind.