Because of the failure of bonding the electrode to the top gasket in my last design, I have been trying to make improvements to my fabrication to make the electrode/gasket surface more planar. Things I have tried: 1. Pressure during curing. I placed a 500g weight on top of a microscope slide on top of…
After integrating my thin film electrodes into the layer stack of the BBB device, I want to make some TEER measurements. I stripped off the well-plate attachment off of the TEER tool, exposing the individual leads. To test that the circuit functioned properly, I placed the leads in DI water and then…
I have been trying to fabricate my own Indium Tin Oxide (ITO) electrodes on coverslips for the BBB device in order to minimize the working distance for any microscopy. Currently, I am using microscope slides that are way too thick (mm). Coverslips are generally about 0.2mm thick. I am using a combination of sputter, photolithography,…
I have created a successfully sealed flow chamber with this current device (V2.4), with the caveat that I sealed off the top chamber and was unable to test leaking from the top to the bottom. Again, the dialysis chips from Dean’s work were used, as well as the same bulk microscope slide electrodes. Improvements…
I’ve made some modifications to my V2 design such that it allows total vertical access, among other things: This design utilizes embedded electrodes and filter within gasket layers to create a tight fluidic seal for each channel. Here, the slot is pointed upward, so the endothelials will be on the bottom side and the…
Found a Master’s thesis from RIT that details etch rates for ITO films in Hydrochloric Acid. I originally attempted to do an etch using 1M HCl, but as the graph shows, this is not enough to produce an etch rate. I found this information out later, as 37% aqueous HCL = 12M solution, from http://openwetware.org/wiki/Hydrochloric_acid. Using…
I recently bought some slides of ITO from Sigma-Aldrich, and have been working to integrate them into PDMS by using the same process as I did for the glass coverslips (seen here) The main differences between the glass coverslips and the ITO coated microscope slides are the ITO film, which seems to have different wetting…
The goal of the design is to design a system that can co-culture cells under varying flow conditions, measure TEER, and perform dynamic microscopy. Specifically, the endothelial tight junctions are the primary mechanism by which the BBB is regulated. It is thought that astrocytes and pericytes can influence this mechanism. With the completed system, we…
As I am hoping to promote tighter junctions between endothelial cells in my device, I am trying to create an environment that produces shear stress on the endothelial cells. Shear stress up-regulates the pathways that promote tight junctions (Tzima et al 2005, Dejanna et al 2004). The value of the quantity is somewhere around 6…
BBB Device Update We’ve identified a few areas in which we can improve upon the initial device seen in Booth et al (2012). Mainly: Endothelial TEER increases to an in vivo value, hopefully from increased astrocytic (pericytic?) support from the abluminal chamber due to better membrane characteristics. Real-time microscopy of endothelial cell tight-junctions under the…