The new oxide chips arrived this week, so I have materials for lots of experiments going forward. The current inventory stands as follows: ~100x NPN chips (mostly still in wafer form) 81x 20nm SiN + 200nm  + 10nm SiN cap 93x 20nm SiN + 200nm oxide Imaging of the membranes shows the expected images for…

Background:  The purpose of these experiments was to investigate the formation of gap junctions between co-cultured HUVEC and ADSC across 0.5µm HP SiO2 and 0.4 µm HP Track-Etched membranes. Gap junctions are channels that allow small molecules to pass directly from cell to cell. Electron micrographs show that the membranes of two adjacent cells are…

Principle of Operation The electrokinetic properties of charged membrane make it possible for conversion between the electrical and mechanical regimes. The electroosmosis is an example of converting from the electrical to mechanical powers. In reverse, exchanging the mechanical energy for electrical energy relies on two electrokinetic phenomena – the streaming potential and current. Consider an…

Jirachai’s recent post on the formation of Au nanoparticles on the surface of the NPN is very exciting. For one, it is a very dense monolayer of particles. This self assembly mechanism is magnificent whereas if we tried to dry down a layer of particles, we would get a cake layer similar to what Josh…

It was expected that heating up the substrate during Au sputtering would help increase mobility of Au into nanopores so that the uniform coating on pore wall could be achieved.  The result was quite unexpected; Au did not coat uniformly on pore wall nor the surface of membrane.  Instead, Au clumped into nuggets of various nanometer-scale sizes all…

After correcting a minor error in my code that was giving me some weird limiting behavior, and optimizing the code to give me faster results, I generated the following curves: Note that, as experiment predicts, the ‘sharpness’ of the graph increases with increasing applied pressure. The model isn’t exact, and slightly underestimates the actual sieving…

Discoloration Assays Introduction: pnc-Si chips were monitored for discoloration to find chips that had not been previously RTP’d. These assays were necessary in order to find chips that could potentially be used for cell proliferation assays later. Setup: pnc-Si chips were autoclaved and placed in a 24-welled plate with 300uL of DMEM and incubated at…

Hi All, Presented in this post is the following paper, titled: “Detection and isolation of circulating exosomes and microvesicles for cancer monitoring and diagnostics using micro-/nano-based devices” [REVIEW] exosome handling in micro and nano devices Keynote presentation: [PRSENTATION] NRG (2015-11-16) exosomes

Introduction After completing my experiments on burst pressure of HD membranes, I started the experiments on finding the burst pressure of 3-channel nitrite chips by using the airgas cylinder. This experiment is to investigate if soaking in viscous fluid will significantly weaken the membrane and lead to burst. The chip was placed on the center…

To supplement our upcoming manuscript, we decided that we needed to provide a visual of how thin our ultrathin SiO2 membranes actually are. To demonstrate the thinness of the SiO2 membranes, in comparison to the commercially available Track-Etched hanging membrane inserts, we performed a co-culture using 0.5µm high porosity SiO2 membranes (thickness ~0.1-0.3µm) and 0.5µm…