November 19, 2009
What's up in lab this week?
In case you're wondering what's happening on the North end of Hays Hall this week, here is a glimpse into the labs:
The non-majors Chemistry class (Che 101) is working on a unit about drugs and how they work. So what better thing to do than make aspirin! Here, Economics major Stephen Popovich '10 admires his unpurified product. Along with its synthesis from salicylic acid, students also evaluated their products by testing for the presence of the reactant phenolic group with iron chloride, took its melting point, and made a second ester, methyl salicylate, which smells like wintergreen.
In Chemistry 111 (the former Chem 3), students determined the identity of an unknown liquid by determining the molecular weight of its vapor. They spiked their samples with rhodamine (which fluoresces pink) to be able to better determine when it was completely converted to a vapor. PV=nRT to the rescue!
In Organic 1 (Che 221), students investigated whether a reaction of alcohols with competing halogens proceeded via a SN1 or a SN2 mechanism. If it's SN1 , the rate determining step is cation formation, and an equal amount of the chlorinated and brominated product should be formed. If it's SN2, the nucleophile plays a role in the rate limiting step, and there should be a significant difference in the amount of chlorinated and brominated product. The students used gas chromatography to determine the ratio of products. Like in all our labs, students operate all the equipment themselves...with fingers crossed that they get results that make sense!
Che 351, Physical Chemistry, uses a round robin approach. Every partnership works on a different experiment in a given week, then they rotate to another experiment until they have completed the entire set. This week they designed their own experiments. Students were using the bomb calorimeter, conducting infrared spectroscopy on HCl and DCl, and doing a couple other experiments, including the one pictured here, where Jon O'Donnell '10 and Lucas Evans '12 are studying bubble formation, with hopes of looking at light scattering on bubbles. When they're done, the students will write a report in the form of a scientific paper, so there is significant amounts of data analysis to come!
Independent projects were also in progress in Che 441, Advanced Inorganic. They ranged from the synthesis of a chiral cobalt compound to the synthesis of cis-platin, a chemotherapy reagent. These are complex, multi-week syntheses, and the students will be characterizing their products over the next several weeks. Here, Jasper Small '10 and Gabriel Stancu '10/11 are making dilutions in preparation for their next step.
So it was a typical week in the Wabash Chemistry labs--students working in teams, using a variety of instruments and techniques to conduct syntheses, analyze samples and solve problems.
Posted by taylora at 11:30 PM | Comments (0) | TrackBack (0)
November 11, 2009
Something's missing at the end of the hall...
Something is missing from the end of the hall.
Merlin Liu, '10, has been camped out in the study nook on the north end of the second floor of Hays since he returned from his summer internship before the semester began. I often see him eating lunch there, studying, sleeping pondering deeply, with his laptop and a large stack of books.
But now the table is empty (though the pile of books remains). Both Merlin and Brandon Hirsch, '10, took the Chemistry subject area GRE (Graduate Record Exam) last weekend. The subject area test specifically measures a student's knowledge of chemistry, and is used both for prestigious graduate school scholarships such as the National Science Foundation Graduate Fellowship Program and admission to some graduate programs (all require the general GRE).
Brandon is planning to go to graduate school next fall and study either analytical or inorganic chemistry, wth the intention of becoming a professor someday. He is currently in the process of applying to multiple graduate schools and hopes to be finished by early December. When I asked him how it went, he commented, "Wabash prepared me with a solid foundation of the basics, which I was able call upon for the test."
When I asked Merlin the same question, his initial response was the way I felt after taking the test--exhaustion and confusion. But he elaborated, "When I reviewed what we learned, everything became much clear and easier than it used to be. Especially organic chemistry, which gave me a very hard time two years ago. The mechanisms ran smoothly like movies in my brain and I did not even need to draw the products on paper."
Wow. Talk about internalizing chemistry! Just like you know you really are fluent in a language when you dream in it, Merlin is dreaming in mechanisms.
I have a feeling Merlin will soon return to "his" study table, as comprehensive exams are looming soon. But in the meantime, congrats to both Brandon and Merlin on a job well done, and best wishes on your grad school admissions process!
Posted by taylora at 10:42 PM | Comments (0) | TrackBack (0)
November 04, 2009
The alphabet soup of cancer
Bcl, Bax, EGFR, Ras, CDK, pINK...the proteins involved in cancer seem like an alphabet soup. But yesterday the Chemistry of Cancer class highlighted what they've about the genes and proteins associated with cancer.
In the 1970's, President Nixon declared "war on cancer", and the search for a "magic bullet" began. As we've learned more about how cells sense their environment and decide to grow (or commit "cellular suicide"), we've also learned that cancer is not a single disease, so there isn't a single cure. For a cell to become cancerous, there must be at least mutations in two different types of proteins--one to trigger inappropriate cell growth, as well as the loss of a growth repressor. These mutations usually occur in proteins involved in one of three main processes in the cell: signal transduction, which is the way the cell senses environmental cues to grow; the cell cycle, which is the process by which a cell divides into two daughter cells; and apoptosis, or programmed cell death of cells with problems in their DNA replication or other stages of cell division.
The ten members of the class each focused on a single protein involved in cancer. They developed a Proteopedia page, highlighting both the structure and function of their proteins. They presented their results yesterday at lunch.
Their findings are also available to the wider scientific audience through the pages they authored on Proteopedia. If you'd like to learn more about their projects, visit the class Proteopedia page.
Posted by taylora at 02:34 PM | Comments (0) | TrackBack (0)
October 27, 2009
Free lunch?
There's a running joke on campus that if you try hard enough, you can eat lunch all week by going to seminars.
That's true this week. And if you've been doing it, you heard some amazing speakers!
Last Friday, Michael Hopkins from the University of Chicago talked about building artificial photosynthesis systems from inorganic materials.
On Monday, Jacob Hale from Purdue University spoke on "Molecular Motion: Interpreting the Dance." His talk highlighted molecular motion of single proteins in a membrane using both experimental data and modeling techniques to refine our understanding of how membranes "work."
Today, Martin Gruebele from the University of Illinois gave a talk entitled "How molecules resemble spacecraft, and how proteins fold in cells." The leap from transition states of simple molecules to protein folding may seem like a huge one, but Dr. Gruebele's analogy of using the gravitational force of planets to minimize the energy needed to take a longer but more efficient route made it all fit together.
And on Thursday, Jeffery Elmendorf from the Indiana University School of Medicine will be talking about "Membrane cholesterol and the Road to Diabetes Type 2." I don't know what's on the lunch menu, but there may be some irony if we're eating pizza and drinking soda during this one!
We are privileged to be able to host such a list of quality speakers. It brings depth and relevance to what we teach in class, and helps all of us keep up with cutting edge research.
What's amazing is that these are just the science talks that happened this week. It doesn't include the African Art Exhibit and associated talks, the Multicultural Festival events, an Ancient Greek sculpture and culture, or Moot Court Finals.
So Wednesday is the only day you're on your own for lunch. Use it wisely!
Posted by taylora at 10:07 PM | Comments (0) | TrackBack (0)
October 14, 2009
Instrumentation and integration
Tuesday the Chemistry of Cancer class donned disposable white lab coats and safety glasses in their visit to Endocyte, a start-up chemotherapy targeting company in West Lafayette, IN. The visit was the culmination of seven weeks of learning about DNA mutation, signal transduction, cell cycle, and apoptosis…and where these processes go wrong in cancer cells. This involved integrating topics from biochemistry, cell biology, organic chemistry, and physiology.
Cancer therapeutic agents generally affect all dividing cells, including hair follicles, and epithelial cells which line the stomach and form your skin, leading to nasty side effects. Endocyte is trying to target chemotherapy and imaging agents specifically to the cancer cells, leading to greater efficacy and fewer side effects. We saw how all aspects of the process are integrated, from synthesizing, purifying, and analyzing potential compounds are to testing them in cells and animals for both specificity and effectiveness.
As part of the tour, Jeffrey Scott Nicoson '97 showed us the various analytical and separation instruments in the lab. At one point, one of the other Endocyte employees asked the students if they had ever submitted a sample for NMR.
Matt Routh ’09 commented, “yeah, I ran some on our 400 MHz this morning.” Our host was surprised to find out that not only did Wabash have a NMR spectrometer, but also the students regularly get to use it themselves, AND we have a higher powered instrument than they do!
Meanwhile, Nathan Line '10 appreciated the automatic chromatography system. He’s continuing a research project he started during his summer internship at The Ohio State University, and appreciated its time saving aspects...but understood the budgetary trade-offs.
The tour went an hour longer than we planned. We made it back for afternoon classes and labs just in time…but it was worth every minute.
This trip was made possible by the Know Indiana Grant from the Lilly Foundation.
Posted by taylora at 12:49 PM | Comments (0) | TrackBack (0)
October 09, 2009
Many paths to summer research
Posted by taylora at 03:21 PM | Comments (0) | TrackBack (0)
February 19, 2008
Global Warming...in the lab
Today the Energy class discussed passive solar heat and the greenhouse effect. To apply what they learned, they built their own solar houses, out of styrofoam shipping boxes and whatever else they thought was appropriate.
Many students chose to use water as a heat sink--this group went to the extreme and lined their house with a black plastic bag filled with water as a heat sink.
Other variables included the color of the box interior, use of reflective material on the inside of the lid, window size and window composition. One group omitted the window completely; while their gain to loss ratio was the highest, the absolute gain in temperature was the lowest. The most creative insulation was a fur hat!
Posted by taylora at 01:16 PM | Comments (0) | TrackBack (0)
