Introduction As a continuation to my previous post, I am running a triplicate of cell culture adhesion tests to observe cell lose on our membranes following physiological shear stress. Methods HUVECs (P3,4,5) were seed within our mimetic and left to grow to confluent for 24 hours. Shear (4.5 dyn/cm2) was initiated and images were collected…
We have a wafer that did not clear 500 nm pores (400 nm thick silicon nitride, #4682). There are about 230 chips that could be useful if they were etched a little. I used a SF6 based recipe (15 sccms O2, 30 sccms SF6, 10 sccms CHF3, 110/10 W FWD/REF power, 5e-5 torr base pressure,…
Microdialysis: Separation of BSA and Cyto C For the past few months I have been studying how well the 75 nm NPN-O membranes are at clearing cyto c while retaining BSA with and without the presence of PEG coating. Additionally, conductivity tests were performed to determine how well the membrane cleared a small molecule. See…
So, I have been working with a 4-probe TEER measurement system to record the changes in endothelial permeability during neutrophil extravasation and other biochemical assays such as thrombin treatment and TNF stimulation. 4-probe systems are sensitive because they don’t suffer from the contact impedances and measure only the potential drop across the sample under consideration. See…
As the first phase of my thesis, I have been working on parylene C membranes as potential easy-to-make thin polymeric membranes for blood brain barrier models following Dr. Carter’s works. The initial goal is to create membranes with different thicknesses with a reliable technique. Method First, the wafers are coated with micro-90 as a sacrificial…
This will be at least a three part series. Here in Part I, we will establish why adding flow to electrophoretic sensor (ssNP) is a bad idea. In Part II we will show why microfluidics is a benefit to adhesion-based sensors. In Part III we will explore the ability of a NPN/ssNP dual membrane sensor…
Introduction/Motivation A problem many of us face in day to day research is the ability to change membrane format in a days to weeks notice. The cost of developing an entire new wafer of membranes for preliminary experiments is costly and time consuming. This cost and time increases when complex formatting is desired. All of…
Hi all, recently we improved cell tracking with the use of SiR-DNA label (see highlights below). random migration: A. Representative cell tracking from three independent migration experiments, color-coded by the color bars to the left in red, green, and blue. B. Distributions of motility parameters (persistence time, instantaneous speed, average speed, pathlength, and displacement)…
In the past, I have been working on developing mechanisms to inhibit neutrophil migration through endothelial basement membrane. Please find the previous blogs on the following links https://trace-bmps.org/updates-on-neutrophil-collagen-migration-experiments/ https://trace-bmps.org/manipulating-neutrophil-migration-through-the-vascular-barriers/ https://trace-bmps.org/sem-imaging-of-neutrophil-transmigration-through-collagen-gel/ This is a small update on the following. CD29 is beta-1 integrins, which are used by neutrophils and endothelial cells to adhere to basement…
Figure 2 – Micro scale Experiments with 10 micron fluorescent particles and 8 micron pore size track etched membranes: A) Fluorescent intensity – time plot showing increasing in the intensity signal during the capturing step and decreasing for releasing step. B,C and D) Before capturing, After capturing and After releasing panels, respectively, including schematic images…