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 one hour. Unfortunately both of these either broke when hooked up to the animal, or…
Discussion: The BSA may have not been fresh enough to give good data, the difference between background and signal are pretty low. The Rhodamine IgG gave better signals but the PEG4 treated SiN is between the untreated SiN and bare pnc-Si. The latter having a lower signal. Here are the details. The fluorescent BSA was…
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 up the dialysis experiments using Sprague-Dawley rats. We made some rats uremic to elevate the…
Sprague-Dawley rats will be purchased from Harlan. These pre-manipulated animals will have been catheterized prior to shipment. We will feed them an adenine rich diet to induce uremia, high levels of urea in the blood. Once uremic, a rat will be connected via blunted needles to the dialysis system. Heparin, or other substances, may be…
This is a cursory review of the nonotechnology articles appearing along with our paper in the Journal “Advances in Chronic Kidney Disease” Most of these are reviews and most deal with nanoparticles for either imaging or therapy. One does discuss nanoparticles for use with membranes to improve biocompatibility. I do not have full access to…
I found some good descriptions of hemodialysis experiments using rats. They all use a method possibly first described by (Rockel et al., 1978). (Galons, Trouard, Gmitro, & Lien, 1996) at U of Arizona used nephrectomized male Spraque-Dawley rats (Holtzmann Co., Madison, WI) weighing ~300 g to study the effects of hemodialysis on the apparent diffusion…
In determining an appropriate animal model for hemodialysis efficacy, several metrics need to be compared to the human vasculature. Blood volume, blood pressure, and heart rate could effect the suitability of these animals to model clinical hemodialysis. Blood volume can be estimated as follows. Blood weight is ~ 7% of body weight, the density of…
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 need to detect urea, BSA, and cytochrome c in serum. Cytochrome c absorbs at 405…
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 (<– trite expression), I redid the experiment with a single tube of serum. The tube…
This is the setup used for the long term clearance testing. The fraction collector can be set to advance to the next collection tube at set intervals from 1 min to 99 min. I am currently conducting an evaporation test with both PBS and 100% serum. I weighed six collection tubes, two were filled with…