As a follow up to my 15 nm post-Si deposition Ar sputter experiment, I fabricated a set of six wafers with 30 nm Si films this week: three with the Ar sputter process and three without. I annealed these at 1000, 1050 and 1100 C with a ramp rate of 100 C/s for 60 s….
The mechanism of organic dye photobleaching is not well understood, but there are a few methods out there for reducing the rate of photobleaching. Some literature suggests that photobleaching is due to excess oxygen in solution and the interaction between the dye and oxygen radicals. Actin research swears by the following “anti-bleaching buffer” to limit…
This is simply the latest repeat of a blood-brain barrier co-culture on PET and pnc-Si transwells. These are P17 bEnd and P24 NG10815, each seeded at 50000 cells/cm2. As usual, I seeded bEnd on the pnc-Si side, upside down, and NG10815 on the well side, facing up. I took TEER measurements every other day for…
In most of the images I’ve posted of bEnd3 on pnc-Si, it seemed like there were more cells crowded onto the free-standing pnc-Si compared to supported pnc-Si. This post shows that this is indeed true. To do cell counts, I stained cells with Hoechst 33342 (1uM in media) for 15 minutes @ room temperature and…
All of my recent posts on VEGF, VEGFR2 and NF-H imunofluorescence have included data from cells grown on coverslips only. This was my first attempt to try to do immunofluorescence staining on intact pnc-Si transwells and then pop the chips out of the transwell plastic in order to image at 100X. Since VEGF is involved…
Recently, I have been exploring the temperature dependence of post-Si deposition Ar sputtered films (15 nm thick). Below is a comparison of the average pore size, porosity, and density of pores of Ar and non-Ar sputtered films annealed between 800 C and 1100 C. It appears that Ar sputtering increases the avg. diameter and porosity…
In order to validate the salt diffusion test I just posted, I’ve been measuring H2O2 diffusion with SC348 and the Amplex Red Assay from Invitrogen. I first showed that H2O2 (=34 Da) passed SC348 in this experiment. Here, I just repeated with slightly different standard curves and positive (‘regular’ Sepcon, SC195 = 4% and 13.9nm)…
About a month ago, I posted some preliminary data that showed NaCl diffusion through SC348. This was motivated by my observation of vacuole formation on SC348. Since my hypothesis is that cell culture substrate permeability is the key factor for vacuole formation, cells shouldn’t have formed vacuoles on SC348. Unless it is actually porous. This…
For my BBB project, I’ve wanted to get nice images of glial cells and endothelial cells on opposite sides of pnc-Si membranes to demonstrate 1) optical transparency 2) that both cell types are in focus (and thus right on top of each other). I’ve gotten some images like that in phase contrast but I also…
Membrane chips were amino-silanized with APTES in the YES system. I performed the standard electroosmosis tests with these chips. Here are the flow rates in comparison with non treated and oxidized membranes: Here are the calculated zeta potentials: As you can see, amino silane reduces the rate of electroosmosis and the zeta potential. We would expect…