To further investigate the mechanism of discoloration, I prepared buffers at different pH’s and measured discoloration and pH over time. Buffers were: 0.1M MES, pH=pKa=6.1; 0.1M Tris-Base, pH=pKa=8.39; 0.1M Tris-HCl, pH=pKa=8.35; 10mM HEPES in 1X HBSS, pH 7.38, where HEPES pKa = 7.31. This was done in the incubator. Experiment 1: Experiment 2: pH vs….
Yesterday, Chris, Dave, Graham and I were (exhaustively) trained on the Asylum AFM in Rick Waugh’s lab. We had an overview of the basic features of the AFM and got some real data, as well. The top panel is a height image of the pnc-Si chip with the well side down. Notice the slight decrease…
Last week in lab meeting, someone wondered if there the time after RTP affects the rate of discoloration. To test this, I RTP’ed chips from w638 in Ar at 800C for 5 minutes. I then followed discoloration in DMEM+10%FBS in the incubator with untreated w638 chips as controls. All of the chips discolored within a…
Last week, I did a couple experiments based on a suggestion by Tom. The pH of DMEM starts out quite high and then buffers down into physiologic range after some time in the incubator. Tom surmised that a short exposure of the chips to high DMEM pH might hasten discoloration. To test this out, I…
Motivated by Tom’s suggestion at lab meeting on Tuesday, I tried “conditioning” the DMEM+10%FBS before adding the chips. “Conditioning” just means that I allowed the DMEM+10%FBS to equilibrate in the incubator for an hour before adding the chips to test if a brief (~1 hour) exposure to very high pH causes discoloration. DMEM+10%FBS without the…
Last week, Lingyun and I deposited 30nm SiO2 onto both sides of wafers 335, 341 and 345. Unfortunately, these wafers weren’t in too good shape, so there are only a few intact slits without pinholes. I then took a few chips from each wafer and did RTP (800C, 5 min, Ar). I’m doing discoloration studies…
I finished the first experiment to look at rhodamine transport across commercial transwell membranes. I was mainly interested if there would be enough transport into the basolateral chamber to measure the rhodamine with the spec. Experimental details: both chambers in PBS and at room temperature, spinning on the rotomix, 0.5mM initial rhodamine in donor; sample…
I’ve been learning the discoloration protocol from Karl and Anant and finally have some pictures of my own to show. We got a couple of new media (RPMI and DMEM/F12) last week in order to grow the cells I’m getting from the Elder lab (rat lung cells). I did a discoloration test to see if…
I’ve been working with the Corning transwell inserts and our SepCon units a bit recently. The addition of the Dremel last week has allowed better control while cutting the transwells, even without the right angle attachment (which will allow cutting in the “drill press” mode). I attached a picture of the process and final unit….