Still trying to reproduce Joe’s large pore material on SEPCONs using NSN stacks. This post has data from two wafers with 30/50/30 and 30/100/30 NSN. RTP is 1000C 50C/s for 1min. Nitride is etched off by placing samples in 50% HF for 3.5 minutes. (~30s after that the films start to lift off) I start…
The Barcikowski lab sent us generous amounts of three different samples – gold, platinum, and bioconjugated gold. Each of the samples was created via laser ablation, resulting in fairly polydisperse (4-50nm diameter) nanoparticles for the pure metal and significantly less polydisperse (2-20nm, not including bound ligand) nanoparticles in the case of bioconjugated gold. As before,…
Hi all, this report will serve both as an update and a template for my upcoming BMES 2012 poster on the shear-free chemotaxis system. Introduction: Because of its capability in hosting reactions and transporting materials in small volumes, microfluidics enables the efficient processing of precious reagents. However, the shear stress inherent in the use of…
New Lift-off setup, thanks to suggestions and concerns about flatness of the membrane after lift-off. Floating SU8 – SiN membrane with superstructure submerged. Membrane after removal from water Membrane, dry on first version of lift-off super structure. Membrane after separation. SiN has adhered to the superstructure and the SU8 peeled off the top. The…
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,…