Here’s the latest news from the production front: We are still struggling with the pinhole issue. Last week, Chris and JP tried a matrix of conditions to try to eliminate the particle contamination. Efforts included using the CO2 snow cleaner and a piranha solution clean. After etching the first wafer which saw only the piranha…
Mike and I tried to pass 3 um beads mixed with rhodamine through the stir cell to prove that, if the membrane we intact, only the rhodamine would pass through and not the beads. As seen in the pictures below, only the rhodamine passed through, not the nanoparticles, since these particles are 100x larger than…
Two more adhesion tests were run recently, one on Tuesday and one on Wednesday. For both tests cells were imaged after five hours. Fibroblast trial 3 was the first test where the optimal cell density (assuming 100% of cells are detached by trypsin and 100% attach to the substrate) was measured using a hemacytometer. Of…
I have tested the new diffusion chamber shown in a yesterday’s post. The idea of our original design works. But there are several problems with this prototype: – Paul used a very thick material to build the clamp, which blocks the objective of the microscope system; – The upper hole in the substrate, designed for…
I ran a few tests with rhodamine to see if the fluorescence will transfer across the cell. The problem I keep having is that the stir cell set-up is very sensitive. If the wing nuts are tightened too much the membrane will break. But if they are too loose the liquids will leak out. Luckily…
The controls of the micropump are in units of frequency, voltage, and wave form, not in flow rates. Based on the manufacturers website they claim that the flow rate has a linear relation with voltage. I took some time to create calibration curves at two fixed frequencies (50Hz and 150Hz). I simply allowed the system…
Just wanted to let everyone know that the fused silica capillary tubing and adapter needed to connect them to the pump tubing have been ordered and should be in hopefully by Friday (Monday at the latest).
Our new diffusion chamber is finally here. Take a look at the photos first – in our next group meeting you can see the real thing. Today I will test its usability and reliability. Please keep in mind this is only the prototype, there must be upside space for improvement.
We have been wondering about the reason for discoloration for a while. This could be due to the pH of the solution or the concentration of the salts in the solution. To narrow down our vision on this, first we tried using solutions with different pH values ranging from 4 to 9 in room temperature….
Thus far three HUVEC and two L13T3 growth tests have been conducted on substrates including glass,pnc-Si, tissue culture plastic, and untreated plastic. Only one test with untreated plastic has been run for each cell type. Cells on Si samples are not on the slits but rather on substrate surrounding. It seems that HUVEC proliferate more…