I assembled two 2-chip dialyzers using the thicker, 75-nm NPN membrane chips (10 mm long multichannel, 22 mm x 24 mm). The dialyzers were pumped full of IPA, to fill with fewer bubbles, then infused with PBS for at least…
Tag: urea
Urea Clearance: First Animal Study Results
BOTTOM LINE: We had great results from the small number of nanoporous membranes used to clear urea from Sprague-Dawley rats. We are clearing Urea better than commercial materials. (see fig) Recap of previous work: First we leaned how to set…
Urea/f-BSA/cytochrome c concentrations in retentate after dialysis: 12 hours
Continuing on the path of hemodialysis, we are increasing the complexity of the fluid being dialyzed. In this long-term experiment I will pump 100% serum with added urea (1mM) cytochrome c (1 mg/mL) and fluorescent BSA (1 mg/mL). So I…
Long Term Urea: Evaporation measurement and Pressure Calculations.
The initial measurements with multiple tests tubes containing either Serum or PBS failed to demonstrate evaporation and in fact the weights of the collection tubes increased after sitting in the refrigerator overnight. Perhaps the tape collected water? At any rate…
Long Term Urea Clearance in 100% Serum
I ran a 30 hour urea clearance with 100% serum through the single slot dialysis device. The now standard protocol was run. The single slot chip was annealed in the RTP for robustness then clamped into the acrylic/PDMS flow fixture.…
Long Term Urea Clearance in Serum
I made 50 mL of 30% fetal bovine serum (FBS), 70% PBS, 0.5 mM urea. Pumped with syringe pump at 5.6 µL/min through an untreated and EA treated single slot dialysis chips in a stirred beaker of PBS (two separate…
The effect of pump rate and channel height on Urea clearance (COMSOL modeling)
Comsol modeling was done to find the ideal channel height and volumetric flow rate. What is clear from the simulation is that ever increasing flow rates in the model lead to increased clearance and decreasing channel heights give some benefit…
Long Term Urea Clearance (8 hours)
SET-UP Syringe pump: 5 mL of 7.6-nmol/100µL, 5.6 µL/min pump rate. Single Channel dialyser, 10 mm long, 0.5 mm wide, 0.3 mm high in stirred beaker of DI water Fraction Collector programed to rotate every 30 min. Set up in…
Single Channel Dialyzer
The main difficulty with creating a simulation of the single channel dialysis chip is that the membrane is so very thin (20 nm). This is especially true when compared to its length of 10 mm but also when compared to…
