Peddie EXP Summer 2018

Charlie updated me with some news about the human islets – it looks like the next shipment will be arriving on August 14 th , exactly one day after I leave SF… But on the bright side, he and Ana will be able to suspend the islets in a hydrogel and load that gel into my hollow fiber cartridges for insulin-glucose response testing. I’m looking forward to seeing some results in the next few weeks, even though I won’t be able to complete the final part of the study. I’ve also done a lot of deeper CAD work with the backside structures of the iBAP device itself. As a reminder, the device faces some clotting issues because fibrinogen, a clotting protein, is small enough to pass through the silicon membranes. If the flow is stagnant, then this fibrinogen attaches to the internal walls of the device and settles down to begin coagulating, shown in the blue (slower flow velocity) areas of the following image.  If the flow rate and shear stress along the walls is high enoug...

So, change of plans on receiving the human islet cells for live testing. I talked to Charlie and he said that the human islet cell supplier might not be able to have any cells in stock for the foreseeable future. The problem with obtaining human islets is that they’re extremely hard to come by, since they have to be sourced from recently deceased, young, healthy organ donors. It’s understandable that there aren’t many “in stock”. I asked Charlie about subbing in mouse islets since those could be harvested at will, but he explained that each mouse only has a small fraction of the islets that a human does, so we would need to sacrifice 80-100 mice for just this project – an ethical choice that I am happy to avoid having to make. Fingers crossed that I receive them before I leave California though! After the past two weeks, I successfully fabricated a few more hollow fiber cartridges that were suitable for in vitro tests. I tested them all for water flow rates with this pump setu...

Hey everyone, These past two weeks have been really exciting. I first tried to tackle the random fiber assortment problem by creating a tubesheet design that could be made with the “Othermill” CNC Mill that we have on site at my lab. What’s cool about this mill isn’t just the name, but the fact that the smallest drill bit it accepts is 1/100 of an inch wide at the very tip. This is about a quarter of a millimeter (or 254 microns if you want to sound fancy). Eric, who works the shop, showed me how to set everything up with the Othermill. I actually breezed through most of the CAD/CAM part, thanks to my experience with Peddie Robotics. The entire machine is about the size of a cubic foot, which is extremely small compared to the behemoth Haas mill that we have back at Peddie. I first milled this cool honeycomb pattern of holes into the back of a plastic petri dish. Ideally, the honeycomb pattern will keep the fibers in an even order with a uniform diffusion radius ...

Hey everyone! It’s been a while since my last blog post – I’ll chalk that up to being so busy these past couple of weeks with lab work and other things. Going into my fourth week at the Roy lab, it’s hard to believe that my time here is flying by so quickly already, but here we are.  After my first week at the lab, I started working on my independent project. As I mentioned before, my lab works with creating bioartificial organ devices, specifically an implantable artificial pancreas. Once implanted, the patients blood goes through the device and through diffusion, an ultrafiltrate is produced by passing the blood across a silicon nanopore membrane (SNM). (here’s a picture of one of those silicon nanopore membranes I keep talking about - the rainbow is from refracted light, not actual coloring)  This ultrafiltrate is mostly just blood plasma, but it has a couple of key ingredients: dissolved oxygen, glucose, and other nutrients. The ultrafiltrate is then fed thro...

Hi Everyone! After arriving in San Francisco last Sunday, I spent this past week settling into the downtown Berkeley apartment that I’ll be sharing with Rohit for the next couple of months, as well as learning my way around the Roy lab at UCSF. First day at the lab was really exciting. Here are a couple pictures of the Mission Bay campus, which was completed just a few years ago. Everything is super new and modern, and there’s still construction for other buildings going on around the campus. Most of the people who work at the Mission Bay campus are either professional researchers or doctors/nurses for the nearby hospital. The graduate students take most of their classes at the original Parnassus campus (where Maya is). I work in Byers Hall, which is connected to Genentech Hall and a short walk down the block from the shuttle stop. There are three other volunteers working for the Roy lab this summer – Kimmai, David, and Pujita, who are all undergrad college students...