First things first, the desalting column is not intended to desalt. Apparently that’s just an old name that has carried over. The current purpose is to separate viruses from large debris after sonication. The sample in a buffer solution will be placed in the center of the cartridge and sonicated in the “glass bead pod”….
In this post, I sum up all the NSN stacks with different Si thicknesses I have made so far. The nitride layer is 30nm thick for both the top and the bottom. The thickness for silicon film ranges from 7nm to 10nm, 15nm, 25nm, 50nm and 100nm. All the wafers were firstly etched and then…
We are trying to reproduce the very small pores Joe created with 30/100/30 OSO and large pores created with 30/100/30 NSN using a SEPCON pattern. (Joe’s previous post.) We had a problem with several chips releasing from the center of the wafer prior to completely clearing all the features. In the future we will use…
Samples of pnc-Si, 5.5 mm x 5.5 mm, were functionalized at Adarza and incubated with fluorescein conjugated BSA. Wells were formed in PDMS to hole fluid above the samples. Samples were wetted with PBS then f-BSA, 5 mg/mL, was added. The samples were placed in petri dishes with DI water soaked Kim wipes; the petri…
We will devote the first NRG meeting of each month to journal club. First up is Karl who will review two papers describing the use of single nanopore membranes as a method of characterizing particle size and zeta potential on a particle by particle basis. The technology produces intriguing data sets like the one shown…
After some changes to my fabrication process, I can report a qualified successful TEER test with media (HBSS) in both channels. I utilized a shrink wrap method of fabrication as seen in a previous post. The test was not perfect because I ruptured the channel while moving the fabricated device to a microscope slide. Also,…
In order to include pumps on the prototype blood analyzer cartridges, it was necessary to implement a small pump using the existing knife-cut PDMS layer layup technique. The diaphragm architecture was selected due to ease of operation and minimal additional part requirements. CAD model of pump in Autodesk Inventor Bottom view of fabricated pump. The…
INT received the first samples of their new cartridge design. The following slides were given to us by INT to provide some detail. The shorter cylinder on the left that is called the “glass bead pod” needs on filter fixed to the bottom. The taller cylinder is the “desalting chamber” and will require a filter…
Because of the failure of bonding the electrode to the top gasket in my last design, I have been trying to make improvements to my fabrication to make the electrode/gasket surface more planar. Things I have tried: 1. Pressure during curing. I placed a 500g weight on top of a microscope slide on top of…