The technique uses a multitude of polymer pyramids that are covered in gold and positioned onto an atomic force microscope. These arrays, which are one square centimeter in size, comprise of thousands of tiny pyramids with holes that permit light through, and make certain that the light goes only to specific places on the surface of a chip below, immobilizing delicate organic reagants on the chip’s surface without damaging them.

 

Processes like this, known as tip-based lithography, are broadly perceived to be the best way to 3D print organic material with nanoscale feature resolution. But in the past, they were limited by the fact that they could only print one kind of molecule at one time.

 

Now researchers at Hunter College and the Advanced Science Research Center (ASRC) at The Graduate Center of the City University of New York think they have sorted that problem.

 

They're using microfluidics, the manipulation of fluids on a molecular level, to expose each biochip to the desired combination of chemicals. Then, they use photochemistry to shine light through the apertures in the pyramids. As the light does respond with the molecules, it cling them to the chip.

 

With typical tip-based lithography systems, the light can overpower the chip, destroying some molecules. But the CUNY research team uses beam-pen lithography, where the light is confined and funneled through small apexes. This allows the team to control the light and protect the organic materials that they have already printed on the biochip.

 

Adam Braunschweig, the head researcher and an associate professor with the ASRC’s Nanoscience Initiative and Hunter College’s Department of Chemistry, says this method of 3D printing biochips can help scientists understand cells and biological pathways. That is because this technology should make it easier and more excellent to analyze disease development and reduce other biological puzzles, such as detecting bioterrorism agents.

 

Source: Tronserve