"We use that theory to analyze the hologram of each object in the snapshots of our video recording," explained Grier, who is part of NYU's Center for Soft Matter Research. "Fitting the theory to the hologram of a sphere reveals the three-dimensional position of the sphere's center with remarkable resolution. It allows us to view particles a micrometer in size and with nanometric precisionthat is, it captures their traits to within one billionth of a meter."
"That's a tremendous amount of information to obtain about a micrometer-scale object, particularly when you consider that you get all of that information in each snapshot," Grier added. "It exceeds other existing technology in terms of tracking particles and characterizing their make-upand the holographic microscope can do both simultaneously."
Because the analysis is computationally intensive, the researchers employ the number-crunching power of the graphical processing unit (GPU) used in high-end computer video cards. Originally intended to provide high-resolution video performance for computer games, these cards possess capabilities ideal for the holographic microscope.
The team has already employed the technique for a range of applications, from research in fundamental statistical physics to analyzing the composition of fat droplets in milk.
More broadly, the technique creates a more sophisticated method to aid in medical diagnostics and drug discovery. At its most basic level, research in these areas seeks to understand whether or not certain molecular components, i.e., the building blocks of pharmaceuticals, stick together.
One approach, called a "bead-based assay," creates micrometer-scale beads whose surfaces have active groups that bind to the target molecule. Because of their small si
|Contact: James Devitt|
New York University