On Wednesday we ran several separations using both the EA and PEG treated membranes. The treatment process had damaged many of the chips. Of the 10 treated 10nm PEG chips, 2 survived. Of the 10 treated 15nm PEG chips,…
Author: Karl Smith
Karl is the 'separations czar' for NRG. As a Biophysics Ph.D. Candidate, Karl has the responsibility of characterizing new membranes, modeling the unique physics of nanomembrane separations, and finding ways to apply pnc-Si technology to protein purification, nanofluidic transistors, and human hemodialysis. Karl graduated from Allegheny College in 2011 with a double major in English and Physics.
BSA does not pass through Peg-lyated or EA treated Sepcons with cutoffs of either 10 or 15nm
Posted in NRG
10 and 15nm Cutoff Sepcons Both Allow Cytochrome C to Pass, but not BSA
In a previous post, we showed that both Cytochrome C and BSA at concentrations of ~1mg/mL through 20nm cutoff Sepcons with about the same filtrate concentration (~60% of the feed concentration). Yesterday (1/14/13) we repeated these experiments with 10 and 15nm…
Posted in NRG
Two Quick Graphs Show That BSA and Cytochrome C Both Pass Through 20nm Sepcons
Before the fresh Cytochrome C arrived, I ran two samples. The first sample was our old Cytochrome C in 0.3mM sodium phosphate buffer at a concentration of ~1mg/mL. I passed it through the 20nm cutoff 3rd generation Sepcons by spinning it…
Posted in NRG
The Concentration of the Barcikowski Peptide is at the Lower Bound of Our Detection Limit
Recall that we’ve been having a great deal of trouble following the free ligand during our separations of the Bioconjugated Barcikowski particles, and that this trouble also means we can’t see the ligand after centrifuging the pure sample. In the…
Posted in NRG
Filtration of Bioconjugated Samples Retains Gold, but We Can't Follow the Ligand
On Friday(which was a great day for science). I ran a series of 5 passes of the bioconjugated gold nanoparticles through 30nm cutoff Gen 3 Sepcons. If you’ll remember, the Barcikowski lab wants the free ligand separated out from the…
Posted in NRG
Inventory of Nanoparticles
Nanoparticles Inventory – taken by Karl on 11/2/12. All these particles can be found in the refrigerator. Manufacturer size type amount (approx) expiration date fluorescence (if applicable) BBI 5nm gold colloid 3mL Jan-10 BBI 5nm gold colloid 6mL Aug-11 BBI…
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More Barcikowski bioconjugates have arrived. Here’s the plan for them.
The Barcikowski lab sent us generous amounts of three different samples – gold, platinum, and bioconjugated gold. Each of the samples was created via laser ablation, resulting in fairly polydisperse (4-50nm diameter) nanoparticles for the pure metal and significantly less…
Posted in NRG
SEM Images of Barcikowski Samples
With Joe’s help, I was able to take some SEM images of the samples that I performed my previous set of separation experiments on. Sample 1: The obvious aggregation in this sample (exemplified by the ‘victory eagle’ blot in the…
Posted in NRG Tagged with: Barcikowski, clumping, dried sample, gold, karl, particles, platinum, SEM
Filtrate Concentration of the Barcikowski Particles Remain Discouragingly Low Despite Larger Sepcons and Higher Salt Concentrations
Because the Barcikowski lab intends to use the nanoparticles they sent us, relatively high yields are necessary for any step that cleans them up. This is unfortunate, because in every single separation that we’ve done (with one exception mentioned further…
Posted in NRG
Barcikowski Particles
The Barcikowski samples, sent from Germany a month ago, continue to be a fecund source of inconsistant data. Using the DLS to monitor several filtrations has resulted in a series of baffling results that I think I’ve finally begun to…
Posted in NRG
