Attached is a paper I’d like to review on Thursday (June 11, 2015). This group is using two planar surfaces in an attempt to mimic a 3D cell culture environment. This is similar to our claims that cells growing on a permeable membrane can be akin to a slice of a 3D matrix. I met…
Pertaining to the tenting work that Greg and I have been doing, some of the experiments discussed on my last post have given us reason to believe that the transferred membranes may not adhere well to silicon oxide, floating just above it rather than sticking to it. As a test for the stability of the…
I spent some time testing the various steps of the transfer and wetting process to see if I could find the cause of membrane delamination that I saw earlier. The result seems to be that time is the main culprit. Here is the membrane just after transfer (dry between the membranes initially, steam after transfer…
My original post reported burst pressures on rectangular windows with the chips trench side down in the fixture (pressure from below). These values are low compared to square window pressures. My pressures ranged from 2 psi to 12 psi while square windows achieved 10 psi to 50 psi (Sarah Wayson’s post on square windows). So I did a limited set…
My first attempt at a nanopore fabrication/DNA experiment in NPN assemblies was interesting but ultimately unsuccessful. As I said in our last meeting, I have been able to reproduce the membrane transfer process (using some steam between the two membranes to make good contact) and the wetting behavior using a freezer to condense vapour on…
Summary Since our last attempt, Greg and I have been attempting to refine our tenting experiments with the goal of demonstrating that we’re able to hydrate the volume underneath a nanoporous tent. This latest experiment is very similar to our previous experiment in theory, but we made some key changes which are discussed herein. Most…
Summary: Annealing to above glass transition T (200 C) doesn’t reduce film stress. Adjusting post-exposure bake protocol seems to reduce it. A short post to document my efforts at reducing tensile stress in SU-8-3000 coatings by annealing in vacuum to its glass transition temperature (200 °C according to MicroChem). This is in relation to the…
Simpore produced a wafer of 50 nm NPN with a matrix of (4) widths X (5) lengths Widths of 100 um, 300 um, 500 um, and 700 um Lengths of 1 mm, 1.5 mm, 2 mm, 2.5 mm and 3 mm Each chip has one membrane. These are the dimensions of the membranes. Using the burst…
Figure 1. A) A TEM image of a SiN nanomembrane. Circles with a rim are pores that span the thickness of the membrane, while grey patches are pits in the surface. B) A pore size histogram generated using image processing software shows that the average minor axis (the restricting axis) is ~ 50 nm. …
This is the final post (hopefully) summarizing my simulation results I did to model Endohm system. Barrett used endohm cup system to do the coculture of bEnd3 and glial cells for his BBB studies. The resistance values obtained while using pncSi and uniformly porous membrane for cell growth were drastically different, and it was not very…