W613, the wafer with 30 nm thick pnc-Si was tested for chemical stability. This wafer was shown to be very weak mechanically, with burst pressures less than 1 PSI. I tested this wafer for chemical stability with cells (fibroblasts, P26) in DMEM +10% FBS (n=5). I also monitored discoloration in DMEM +10% FBS w/o cells…
In an attempt to improve membrane life in cell culture, different RTP times were tried on a single wafer. Samples from W514 were RTPed in Ar at 800C for 1, 5, and 10 minutes, respectively. Cells were then seeded at confluence on membranes, with membrane stability monitored for breakage. Discoloration was monitored on samples without…
Last week I ran cell culture growth experiments on RTPed (800C 5 minutes in Ar) samples from W567 (single slit 100um x 1000um). For this study I tracked discoloration w/cells, membrane stability w/cells, and the bead assay w/cells to see if we can predict if a membrane used in cell culture is intact by monitoring…
Time lapse movie of fibroblast spreading on the nanomembrane was captured over a period of ~ 8 hours. I was having some problem uploading the video here, thus have done so in the NRG knowledge page under the cell culture manuscript.
I recently received wafer 567 from Dave for cell culture work. It has many intact membranes but is riddled with pinholes, having only 3 pinhole-free samples. I decided to test them for air permeability and burst pressure, shown below. I also noticed some odd features on the membrane and surrounding Si. They are circular but…
Couple of HUVEC adhesion trials were carried out and the results were found satisfactory as seen in the charts below.
HUVEC growth was monitored for 4 days on different substrates (glass, plastic and pncSi), this time in media (EGM) with and without serum. Growth in media w/o serum was observed to be much slower than the growth in media with FBS. Hence, media w/o serum can be used as a possible control for the growth…
HUVEC adhesion was tested on different substrates. This time solid chips w/o membrane slits were used and expected results were obtained. I think from all the adhesion studies done, it could be concluded that initial adhesion on pncSi is as good as any other favorable substrate. Hence, the initial low density on pncSi was due…
HUVEC adhesion was measured on glass, tissue culture plastic, and pnc-Si, with poly-lysine coated plastic and teflon coverslips as positive and negative controls. Adhesion on pnc-Si was low, this could be due to cells being lost through broken slits or possibly some other unknown factor. Adhesion tests are continuing, with the use of solid Si…
Fibroblast adhesion experiment was done using poly-lysine coated plastic and teflon coverslips as positive and negative controls repectively. Poly-lysine is a polypeptide that gives the cells a sticky surface to adhere to. Teflon coverslips are used as negative control because they do not promote cell adhesion. Difference in morphology of cells could also be seen…