Microfluidics

[alexander]

Hey, I was clicking around on the net, and accidentally came up on a Microfluidics research paper. This is what it said, mainly:

"So-called "lab-on-a-chip" technology, which combines microfluidics (liquid handling on a nanoliter to femtoliter scale) with microfabrication techniques developed by the semiconductor industry. The resulting chips, some no larger than a computer microprocessor, perform biochemical reactions from many tiny samples in parallel, in theory reducing costs and conserving reagents while greatly improving speed and reproducibility for both diagnostics and drug discovery. And, they fit easily into automated workflows.

 

Cell-based assays in particular are time-consuming and reagent-hungry. This can be especially problematic for primary cells, which can be difficult to produce in large numbers. Caliper is one of a number of companies pursuing this need. According to Boudreau, Caliper's LabChip 3000 can screen drugs against such targets as G protein-coupled receptors, using cell-based calcium-ion flux assays.

 

Cells are driven through tiny channels and exposed to a library of compounds. Calcium influx is measured, one cell at a time, using fluorescence. The chip uses "one roller bottle of cells in place of the fifty" that would be needed to screen the same number of compounds using conventional microplates, says Boudreau. The same chips can also perform protease, kinase, and phosphatase screens.

 

BioProcessors of Woburn, Mass., also addresses the need for faster, cheaper cell cultures. Instead of using the cells to screen drugs, the company uses the cells to make them. BioProcessors has developed microfabricated bioreactors in which cells can be grown, harvested, and analyzed in numerous tiny, parallel cultures. These "SimCells" allow rapid testing of multiple growth conditions for their effects on drug production. And they can be adapted to grow different types of cells, including bacterial, fungal, and mammalian.

 

In the future, cell-based systems may become even more complex, integrating more functions onto a single chip. Pennsylvania State University associate professor Michael Pishko is working to develop chips containing "arrays of different phenotypes of cells." For example, a single chip might contain liver, immune, and vascular endothelial cells, he says. Compounds flow past the different types of cells, and fluorescence is used to detect their effects on various aspects of cell function, such as nitric oxide production. These chips could be used in cytotoxicity assays, Pishko says.

 

High-performance liquid chromatography (HPLC) is another tool that is making the transition to microfluidics. Companies such as Eksigent are using lab-on-a-chip technology to make HPLC "faster and multiplexible," says Jensen.

 

Eksigent is an anomaly in the field, Jensen says, in that it has "integrated microfluidics technology into a hybrid system" that does not involve an actual chip. He says the original focus on complete lab-on-a-chip strategies limited the potential benefits of the microfluidics technology. "Is there inherent benefit in the chip format? Does everything have to be on a chip?" he asks. His answer: "If the chip limits performance, don't use it. [Researchers] want the system that gives them results."

 

Eksigent's NanoLC system performs HPLC 10-times faster than do conventional systems, Jensen says, using currently available liquid-handling technologies. This acceleration should allow researchers to expand their use of HPLC to investigate the physical and chemical properties (such as solubility and pKa) of many more drugs before they enter the development pipeline, he adds. Eksigent has also developed the NanoLC-2D system for proteomics applications. "

 

And so forth.... My question is: why aren't we using this technology in pharmacies and doctor offices, why aren't we using it in a lot of researches and fights against diseases and biological along with chemical weapons? Won't this type of technology totally speed up the processe