As discussed in a previous post “Clearance, Kt/V, and Concentration…”, we will use the Kt/V metric to measure the effectiveness of dialysis. There are other methods that are used: one of these is the Urea Reduction Ratio, URR. URR is a fractional decrease in Blood Urea Nitrogen, BUN, in a single dialysis session. It is…
Jirchai summarized his data in this table … A question raised by a reviewer of our PNAS submission – and one that we’ve had for a long time – is what is the efficiency of the pump. The electrical power provided is calculated in the table for each configuration. As Chris mentioned in group meeting,…
Dialysis Rate: 10 mL/min, Péclet Number: 1, Membrane Width: 700 µm, Channels per chip: 17 Péclet number Pe ∝ H Pe ∝ 1/L Pressure Drop, P P ∝ 1/H3 P ∝ L
When we submitted the EO paper way back one of the reviewers made the following comment … What is the “head pressure” P_max, i.e. the maximum back pressure that would stop the pump? For any linear electrokinetic phenomenon such as EO pumping, the flow rate decreases linearly with backpressure until a certain point (“head pressure”)…
The urea assay is straight forward. 6 wells are filled with 0, 1, 2, 3, 4, and 5 nmol of the urea standard (50 nL). Each well is activated with 50 nL of the reaction mix. Reaction Mix Sample control Urea Assay Buffer 44µl 46µl OxiRed Probe 2µl 2µl Enzyme mix 2µl 2µl Developer 2µl…
In my previous post of Morphology evolution in pnc-Si membrane (2), see https://trace-bmps.org/datablog/?p=14769&preview=true , I showed that membranes (30SiN-25Si-30SiN) annealed at 700C show us an intermediate morphology in the pnc-Si membrane. I did some further investigation in the past week on this intermediate morphology. Compared with the previous test which membrane was annealed at 700C…
On Monday I presented our progress on the hemodialysis project for the Coulter Foundation. They seemed very pleased with our progress and impressed with our team. Its a tough crowd and for the first time, I sensed they had confidence in us. I’ve uploaded my presentation to the blog (PDF; ppt). Their primary points of…
This is the third set of studies to assess the hemocompatibility of pncSi. It aims towards a quantitative analysis of the formation of the complement protein C3a in the blood upon interaction with pncSi surfaces. Biological Motivation: Complement proteins help the functioning of the innate immune systems in clearing away the pathogens from the organism,…
See Microfluidic Mold Making for instructions. I have assembled 3 more Barrett Chamber/ SC114 pnc-Si microfluidic devices this week. Currently, there are 2 Barrett chambers remaining and the mold is missing. The mask to make the mold still exists, however, there was a lack of N2 gas for processing (spin-coater requisite), so Henry and I…
Barrett Chamber Flow Visualization For my lab rotation here, I was tasked with visualizing the flow of blood/blood-like objects across the 1st generation Barrett chambers. The design of the chamber is seen below. Some key characteristics are that the chamber is suspended from resting flat on a surface to allow liquids to diffuse through the…