Repeated Success with Flow System
Yesterday I started a test to try and reproduce the results Henry was able to obtain with a closed flow system last week. Using four samples (W619) I ran the UV Ozone bonding process and allowed them to sit over night.
This morning I found that only one of the four samples was bonded; recently I have been getting 100% bonding efficiency. Using this one sample I used a healthy amount of vacuum grease to seal the opening near the PDMS-pncsi and capillary tube interface. When I attached the system to the micropump I was able to get flow through with no leaks.
When I transfered the system over to the microscope to begin taking pictures and making a movie using microbeads one of the capillary tubes moved and became clogged with vacuum grease. When I tried to get flow again the system leaked due to the clogged tube.
So, since that was the only bound system from yesterdays run I am going to have to make a new batch of systems today and repeat the flow experiment tomorrow. But at least we now know that we can use vacuum grease by itself to get a system that does not leak. Also, later this week Henry and I are going to try to go over to RIT and use the new wafer to try some anodic bonding.
Mike – these experiments really need to be done on a fluidic breadboard to support the tubing and components as you move it around. Jim seemed to recognize the names of the 2 companies that make these microfluidic components, as we saw at Brian Kirby’s lab at Cornell. No one who works with microfluidics uses these tiny tubes and components in a free-standing format. There should be plenty of option out there…