I few weeks ago I posted some flow rate data based on the 100K microcons in which three of the four membranes worked fine and the other appeared to be a “dud”. I pulled the four systems apart and used the digital calipers to measure the membrane thicknesses and found the following. – The three…
I used the EQ format to test the 100K microcons in a wet-wet trial using DI water. The below illustrates a comparison between the hydraulic permeability of the 100K microcons in a wet-dry format (from tests earlier today) vs. a wet-wet format. The group on the left (1) represents the wet-dry tests done earlier today…
I reran the 100K Microcon membranes using bovine albumin. This time I ran a set of four fresh membranes with DI water for a preliminary trial. Once complete I used two of the same four membranes with a 1mg/mL solution of bovine albumin in PBS to test the effects of protein; the other two membranes…
The 300K nanosep membranes that Jess ordered came in so I ran a single set of three membranes at 21.63psi to compare their hydraulic permeability values to those of the 100K microcon membranes. As expected the 300K nanosep membranes have a much larger hydraulic permeability then that of the 100K microcons; approximately a factor of…
Having finished the hydraulic permeability testing with DI water I wanted to see what the effect of an introduction of protein would have on the permeability values. To do this I simply reran a set of fresh membranes at 21.63psi using a 1mg/mL solution of bovine albumin in PBS instead of water.The group on the…
When I first starting testing the microcon filters I noticed that if they were allowed to sit overnight (exposed to air) after having been already tested with water the next day if they were tested again the permeability of the membrane decreased significantly. The membranes come pre-wet with trace amounts of glycerin; spinning with water…
last week I ran some tests using a single 100K microcon filter; this week I preformed essentially the same tests but instead of testing one filter over the entire pressure range I used a new filter at each pressure. I tested the permeability at 1.35psi, 21.63psi, 118.7psi, and 267.1psi; each pressure was tested using three…
I ran the same 100K microcon system through numerous pressure ranges and put together the spread of hydraulic permeability results.These results show that the hydraulic permeability of the microcon membranes decrease with increasing pressure. Once I finished running the tests at these pressures I reran a test at 19.52psi (3800RPM) to see if we would…
This week I tried to run a few “eq-tests” with some samples from wafer 187 to get some hydraulic permeability value for our membranes to see how they compare to the polymer filters used in the microcon and nanosep systems. Unfortunately I have no results to report, of the two samples I tested one broke…
I reran a set of hydraulic permeability tests at 16.56psi (3500RPM) hoping that this would clarify the previously collected data at the 21.63psi (4000RPM) and the 33.79psi (5000RPM) range that did not seem to agree with the trend of the other data points. As shown above this point still does not seem to be in…
