There have been differences between the previous long term discoloration studies carried out by myself and Barrett. Couple of reasons speculated for the differences were: 1) Wafer variation (w683 vs w704); w683: has no visible pores, is more amorphous in…
Author: Anant Agrawal
Maximum stability in cell culture conditions
This experiment was carried out to determine the maximum life of pnc-Si in cell culture conditions based on discoloration. All the discoloration slowing factors were put together to see how long would the membranes last for. These include: samples in…
Discoloration Array (revisited)
I repeated Barrett’s discoloration array experiment (Array1, Array2). NaCl solution was prepared @ concentrations: 0, 0.25 (0.1), 0.5 and 1M, whereas NaHCO3 solution was prepared @ 0, 0.475, 0.95, 1.90 (and 3.80) mg/ml. Different combinations of both these salt solutions…
Day4:Cell Adhesion/Spreading/Growth (Trial 3)
After four days of this ongoing HUVEC culture in pncSi transwell, HUVECs look much better than before. Here I have freshly stained them with Calcein AM and we can see how bright it is in comparison to CMFDA stained cells…
Day2:Cell Adhesion (Trial 3)
On Day 2 of cell growth from trial 3 of adhesion study, cells looked much more spread out but less in density. Most of the cells were observed to have concentrated near the edge of the pnc-Si chip near the…
Cell Adhesion (Trial 3)
Samples (no RTP) from W673 and W684 were taken (four from each wafer; with atleast one blank chip) in Sepcons and HUVECs were plated @ ~19,000 cells/sq. cm. density. Cells were allowed to adhere for over 4 hours and this…
Contact Angle Study
According to recent cell adhesion studies on aminosilanized pncSi, no significant difference between adherence to the silanized and non-silanized surfaces was found. This could have been due to the adsorption of protein from the cell growth media onto the surface…
Cell Adhesion Study (Trial 2)
I repeated the previous experiment, this time plating slightly higher density of cells: ~15100 cells/sq.cm. Samples were from the same W673, no RTP) After counting the cells stained using Calcein AM, % Adhesion w.r.t the cells plated were found to…
Cell Adhesion Study (on silanized surface)
We have seen before that silanization slows down discoloration and hence prevents membrane degradation. In Sepcon, the sample should last over a week. Further, it was necessary to check whether silanized surface supports normal cell growth. Therefore, comparison of cell…
RTP + Silanization (3D format)
As seen before, in 2D format ‘RTP+silanization’ helps. Similarly in 3D format, with membrane side down, the same treatment helps prevent discoloration till 5 days. (samples from W413) Above figure shows how combined effect of RTP and silanization is better…
