The device has 56 separation channels with a length of 4cm, a width of 50-150µm, and a depth of 5-18µm. The channels are packed with vertical micro-cylinders. These pillars are 1-5µm thick, and are separated by gaps of 1-0.1µm. Within one channel, all pillars have an identical shape, size, and distance. The chromatograph was implemented on a 200mm Si wafer.
First, a Si oxide layer was deposited on the wafer, on which the submicron structures of the chromatograph were patterned and etched. Next, with the Si oxide layer as hard mask, the separation channels and the pillars were etched with deep reactive ion etching (DRIE). The separation channels were then connected via wider interconnecting supply channels. A 200mm glass wafer was bonded to the Si wafer, serving as a roof to close off the open separation channels. And last, access holes were etched through the back of the Si wafer.
A comparison with commercial chromatographs with macroscopic tubes shows that the micro-chromatograph is 5 to 10 times as fast, and has a better separation capacity. Also, unlike with macro-chromatographs, the separation does not degrade with higher velocities of molecule transport. The performance of the chromatograph was tested by injecting a fluid with tracer molecules in the chromatograph and following the velocity and width of the resulting tracer band.
Liquid phase chromatography is a powerful technique to separate and identify molecules. It is used, for example, in biochemistry labs to separate proteins. The molecules, suspended in a liquid, are separated by forcing them through macroscopic columns filled with micron-sized, randomly packed spherical particles. This sub-micro chromatograph validates fluid dynamic computations that predict that injecting molecules though a submicron maze of perfectly ordered structures will considerably increase the separation speed of liquid phase chromatography.
Katrien Marent | alfa
Explosion on Jupiter-sized star 10 times more powerful than ever seen on our sun
18.04.2019 | University of Warwick
In vivo super-resolution photoacoustic computed tomography by localization of single dyed droplets
18.04.2019 | Changchun Institute of Optics, Fine Mechanics and Physics, Chinese Academy of Sciences
A stellar flare 10 times more powerful than anything seen on our sun has burst from an ultracool star almost the same size as Jupiter
A localization phenomenon boosts the accuracy of solving quantum many-body problems with quantum computers which are otherwise challenging for conventional computers. This brings such digital quantum simulation within reach on quantum devices available today.
Quantum computers promise to solve certain computational problems exponentially faster than any classical machine. “A particularly promising application is the...
The technology could revolutionize how information travels through data centers and artificial intelligence networks
Engineers at the University of California, Berkeley have built a new photonic switch that can control the direction of light passing through optical fibers...
Physicists observe how electron-hole pairs drift apart at ultrafast speed, but still remain strongly bound.
Modern electronics relies on ultrafast charge motion on ever shorter length scales. Physicists from Regensburg and Gothenburg have now succeeded in resolving a...
Engineers create novel optical devices, including a moth eye-inspired omnidirectional microwave antenna
A team of engineers at Tufts University has developed a series of 3D printed metamaterials with unique microwave or optical properties that go beyond what is...
17.04.2019 | Event News
15.04.2019 | Event News
09.04.2019 | Event News
18.04.2019 | Life Sciences
18.04.2019 | Physics and Astronomy
18.04.2019 | Life Sciences