The new bottle of PVP (polyvinylpyrrolidone) sitting on the shelf was calling my name this morning. I apologize that this post is long, but its pretty exciting – I think we have half-solved the wettability problem. According to MSDS sheets, PVP is soluble in water and alcohols. Since drying water on the membrane is a…
Below is an image of HUVEC grown on RTP treated W303 for 72 hours. The cells were seeded at high density and therefore reached confluence prior to day 3. The first row shows the membrane area of the sample; the membrane is not intact. The second row shows the edge of the sample. Live and…
Wafer 416-T is a TEOS wafer annealed at 900 C. Pinhole density is relatively low. left: (1,0) @ 35kx; right (0,4) @ 35kx left: (1,0) @ 50kx; right (0,4) @ 50kx
TE membranes were first embedded in plastic material and then these samples were cut with microtome and imaged. The images below are of the 30nm and 80nm pore diameter membranes. 30nm ones came out better. It looks like the diameter isn’t really 30nm, look at the second picture. The dark spots are either tears or…
Wafer 398 was deposited on 2/14/2008 but just etched yesterday in the new cell (it’s a beauty esp. when you compare it to the old one). I’ve etched several wafers now in the new cell and none of the membranes show signs of cigarette burns or tears. Good news in regards to the copper contamination…
Wafer 415-T has been delivered to the lab. It was processed with TEOS and annealed at 950 C. There are a few usable samples, especially along the edge of the wafer. Pinhole density increases as you move towards the center. The uniformity across the wafer is good. From left to right, top to bottom: (0,1)…
Most recently I’ve been working with colloidal gold nanoparticles (referred to as AuNP from here on). We chose to use AuNP for separations because it is an ideal hard sphere particle, unlike a floppy protein. We thought we could achieve more information about the cutoffs or the sieving characteristics of the membrane by using such…
Transferred from other blog… Wafers 398 and 418 were recently tested for burst pressure. Wafer 398 had a burst pressure range of 4.28-8.24 psi, with the great majority of intact membranes on the wafer having no or one tiny pinhole. When removing samples from this wafer more shards than usual were created, with some fragments…
The new sputtering system is scheduled for delivery at the end of June. It will bring several advantages over our current system; which translates (hopefully) into stronger and more consistent material. 75 days… AJA Sputter Full Blueprint
In order from left to right: 1) t=0, huvec on pncSi, in EGM (10% FBS) 2) t=24 hrs (cells reach confluence) 3) DIC after staining 4) FITC (live cells) 5) Rhodamine (dead cells) Its good to see the cells reach confluence and the membranes intact at the same time! There is a decrease in number…