I finally got some MATLAB code working which calculates permeability coefficients (P, in cm/s) from a non-sink, generalized equation.  This data is from (n=5) fluorescein (MW~370 Da) transport experiments in the Tecan (time vs. receiver well concentration (Cr) values).  In…

This post shows that C-dots are pretty close to neutral.  Here I’ve looked at gold nanoparticles and albumin. 5nm Gold: The distribution is very spread out, but everything centers around -58 mV. 10nm Gold: This sample looks a little bimodal. …

I’ve tried to collect some information on the protein ladder that we’ve been using for separations.  Sizes have thus far been taken from crystal structures and loosely measured used JMol on the PDB site.  This is meant to just give…

I used 100kD Millipore Celllulose membranes to separate the 2 C-dot particles.  The results are similar to those I’ve obtained with pnc-Si; the 10nm particles pass while the 30nm ones do not. Cy5 10nm particles: Sulforhodamine 30nm particles: Here are…

This post outlines two sets of polymer membrane separations using 100kD PES and 30kD cellulose in diffusion mode.  The 100kD PES experiment is a repeat of the experiment found here; in the first trial of this work, there was no…

I performed separations using C-dots from Hybrid Silica, a silica based particle with an internal fluorescent core.  The particles are coated with a PEG layer of unknown length, but the idea would be that they’d be less affected by electrostatics…

There has been some experimentation recently on trying to form very large pores in thick membranes.  We have found that a high temperature anneal (1000 C) along with a fast ramp rate (100 C/s) w/o the susceptor can create these…

For the last three weeks, we have increased the substrate bias power from 25 W to 32 W (for both oxide and a-Si) to adress some film quality issues.  I have found that it is “harder” to open pores in…

I have been working on using the membranes to trap blood cells so that I can take force measurements with the AFM.  It is impossible to perform AFM on blood cells resting on a coverslip because the water displaced by…

Dave gave me some carbonized samples several weeks ago to test stability/discoloration.  I measured the contact angles right after I got the samples (posted here) and then started the discoloration.  These are SC141 chips.  Controls were untreated (1st column) and…