Hybrid silica studies the size of their particles by fluorescence correlation spectroscopy. I used our dynamic light scattering instrument to see what sizes it would get from these particles. Their 45nm particles: Avg center of peak = 46.2 nm Avg width = 15.6 Their 22nm particles: Avg peak center = 27.8nm Avg width = 7.5nm…
Here’s my ‘blog’ post using Google’s Picasa photo album: A few weeks back I received nanoparticles from Ithaca startup company called Hybrid Silica Technologies (HST). They are silica particles that are infused with fluorescent dyes that are generally similar in size and coated with a PEG layer, suspended in DI H20. I chose to work…
I obtained some perplexing results today that I have re-run multiple times. Ozone treating w504 permits the passage of water in a wet/dry format w/o PVP coating. I ran several experiments with the constant pressure device with water on the top side and dry on the bottom. Some of the membranes had once been wet/wet,…
Four more adhesion experiments were carried out and the results can be seen in the following charts. Based on the average of the four trials it can be elucidated that the initial adhesion (after ~7 hours) is pretty much the same in all the substrates. In trial 3 & 4 it can be seen that…
I’ve updated the figure from this post to add new data from oxidized and pre-washed glass samples. We now have possession of teflon material, which I will be testing this week.
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…