Chemistry

The Periodic Table of Videos from the University of Nottingham has 118 short YouTube clips about the elements. Wired Campus recommended the Sodium clip (below). I liked it, too. It's not quite as funny as Mentos in Diet Coke, and but it's still cute and the narrator has a haircut like Gene Wilder in Young Frankenstein. H/T: Wired Campus.
The statin class of cholesterol-lowering agents is rich with history and lessons in the power of natural products, the potential of the prepared mind, and just how precarious the path of drug development can be. American Scientist, the official publication of the scientific research society Sigma Xi, hosts this issue an absolutely lovely article entitled, "Statins: From Fungus to Pharma." Expertly and engagingly written by University of Pennsylvania biology professor Dr Philip A Rea, the article launches with the story of a then-young Japanese biochemist, Akira Endo. (Evidence of my…
As I was looking for a good sangria recipe some weeks ago, I came upon this article in Gourmet about how our understanding of the scientific basis for "flavor" as changed, not to mention what sorts of implications this might have for those who prepare -- and sell -- food. One of the interesting bits is how different the science on taste is from what you probably think it is: [N]early everything humans think they understand about taste is wrong. For generations, textbooks have trumpeted two universal truths about taste. Truth No. 1: There are four basic tastes--bitter, sweet, sour, and salty…
Because Abi asked me to, I'm going to discuss the fascinating case of the Hellinga retractions. Since this is another case where there is a lot to talk about, I'm going to take it in two parts. In the first part, working from the Chemical & Engineering News article by Celia Henry Arnaud (May 5, 2008) [1], I'll focus on the common scientific activity of trying to build on a piece of published work. What happens when the real results seem not to fit with the published results? What should happen? In part 2, drawing from the Nature news feature by Erika Check Hayden (May 15, 2008) [2], I…
Over at Philosopher's Playground, Steve Gimbel asks why the philosophy of chemistry is such a recent discipline given how long there has been serious activity in the philosophy of biology and the philosophy of physics. He floats a few possible answers -- as it happens, the same options those of us who actually do philosophy of chemistry encounter fairly regularly. After responding briefly to these possible reasons for thinking that there shouldn't be a distinct philosophy of chemistry, I'll offer a brief sketch of what a philosophy of chemistry might be about.* (1) There are no big questions…
On 8 May after a six-month search by a 21-member search committee, 43-year-old chemistry professor H. Holden Thorp was named Chancellor of the University of North Carolina at Chapel Hill. The search committee was unable to find anyone else nationally or internationally that could match Thorp's promise in leading the university. Thorp is a pretty amazing guy for any age, having already achieved full, distinguished professor status, chair of the chemistry department, dean of arts & sciences, started a couple of companies, directed and rejuvenated the university's aging planetarium, and…
tags: ice-nine, supercooled water, physics, chemistry, thermodynamics, streaming video This is a fun little experiment with water that was supercooled to -21C (-6F). The supercooled water is poured into a bowl. It pours out as a liquid and turns to slush, forming ropelike peaks [1:07]. What are the physics behind how water can be supercooled without freezing into a solid? It happens like this; when water is supercooled but remains undisturbed, it does not freeze into a solid unless there is an impurity present (a rough surface, for example) for the cold water to crystallize around (a "…
APRIL was so much fun, that I thought I should find a molecule for May. I searched both the Gene database, the structure database, everywhere, without any luck. Finally, I decided to change the search and use the date instead of the name of the month. And here we have it, straight from PubChem. A molecule for May. 05012008 is the compound substance ID. 5/1/2008 Update: This structure turned out to be a bit surprising. Not does it look highly reactive, it also seems to disappear in the PubChem database. Sometimes I can find it by using the SID, sometimes I can't. I hate that. For those of…
Molecule of the Day has a post up about isotopically-enriched food that caught my eye for a couple of reasons. Firstly, the idea is wildly outrageous, and, secondly, this is something that actually gets joked about quite a bit in an NMR (nuclear magnetic resonance) lab. Any given element can come in various isotopes, which differ in the composition of their nuclei. The nuclei of different isotopes of the same element have the same number of protons, but they vary in their number of neutrons. Because the number of neutrons in a nucleus does not significantly affect the chemical properties…
Just a little blurb in my local paper this morning that is making a big splash in the stock market: international pharma giant GSK is purchasing Cambridge, MA-based Sirtris Pharmaceuticals Inc. for an estimated US$720 million. Glaxo plans to bolster its pipeline with Sirtris's experimental biotechnology treatments targeting aging-related diseases. In early trading, Sirtris shares gained 81.6 percent to $22.21 while Glaxo shares added 19 cents to $43.92. Apparently I should've gone immediately from my morning bathroom newspaper reading to my online stock purchase website. Instead, you get a…
Actinomycin D was the first antitumor antibiotic isolated from Streptomyces parvallus cultures by the lab of 1952 Nobel laureate, Dr Selman Waksman, at Rutgers University. However, it took a young Chinese physician and the confidence in her by a future US Surgeon General for this natural product drug to positively impact the lives of children with cancer. An unusually engaging Boston Globe obituary by Gloria Negri caught my attention this week that announced the death of pediatric oncology pioneer, Charlotte Tan (Hsu), MD, of pneumonia on 1 April in Brookline, MA. Dr Tan's 1959 paper in…
Epicauta pardalis - spotted blister beetle Tucson, Arizona Here's a beetle so toxic it can kill a horse. The horse doesn't even need to ingest the beetle, it just needs to ingest something that the beetle bled on.  Blister beetles produce the defensive compound cantharadin- the active ingredient of the aphrodesiac Spanish Fly- which they reflex-bleed out their joints when threatened: photo details (top) Canon 100mm f2.8 macro lens on a Canon 20D f/13, 1/250 sec, ISO 100, indirect strobe in white box. (bottom) Canon MP-E 65mm 1-5x macro lens on a Canon 20D f/13, 1/250 sec, ISO 100, flash…
Since March is Women's History Month, I thought it might be appropriate to recognize some women who were a part of my history -- namely, the women who taught me chemistry and physics. (This shouldn't be interpreted as a slight against the women who taught me biology -- I simply don't remember them as well -- nor against the men who taught me science. They made an impact on me, but this post isn't about them.) I didn't realize it until just now, but none of my science teachers in junior high or high school were women. That strikes me as kind of weird. In contrast, during my undergraduate…
This issue was brought up by my fellow blogger, Joseph at Corpus Callosum, following an article in yesterday's LA Times. For those not familiar with the concept or countries other than the US where laws may differ, generic drugs are those with the same active chemical as the originally-approved "brand name" drug. The original drug manufacturer is the one that conducts all of the preclinical and clinical safety and efficacy testing, natural product isolation and/or chemical synthesis, formulation with inactive ingredients to assure dissolution and reproducible release of the drug, etc. In…
Yesterday, we received tomorrow's issue of the New England Journal of Medicine and, yet again, I nearly walked into a tree coming back from the mailbox. This (abstract, full text), folks, is a fascinating medical detective story rivaled only by (and similar to) the discovery that Parkinson's disease could be caused by contaminant from a faulty clandestine synthesis of an analog of the opiate, meperidine. (1979, 1983) Here's the backstory: in the US, our newly-implemented restrictions on ephedrine and pseudoephedrine OTC drug products are due to the use of these chemicals as starting…
At the beginning of my adventures in blogging (circa 2006) I wrote a short piece for the news site "Mixeye" about the drug fentanyl, and was reminded of it after having a discussion about the drug with some friends. Fentanyl is an extremely potent painkiller, which has unsurprisingly led to its widespread abuse (especially in my neck of the woods, towards Detroit). However, after re-reading my write-up, I was reminded of why I thought this drug was particularly interesting: it has been used in some high-profile bioterrorism strikes and was, for a while, pursued as a chemical weapon by…
Bisphenol A (BPA) is currently one of the major lightning rods for controversy in consumer products and public health research. The compound is used in the manufacture of plastic bottles, polycarbonate (PC) in particular, as well as in the lining of many food and beverage cans. The compound has been recognized since the 1930s as having estrogenic activity but it appears to have developmental, carcinogenic, and neurotoxic effects at concentrations well below those at which it binds to the two forms of estrogen receptor. Confused? US governmental advisory committees can't even agree on BPA…
tags: Kitchen Science, elephant toothpaste, chemistry demonstration, streaming video Elephant toothpaste is a classic chemistry demonstration that will make anyone overflow with joy. When hydrogen peroxide decomposes, it gives off oxygen gas and water. Under ordinary circumstances, it breaks down very slowly, but potassium iodide can act as a catalyst -- making the reaction tremendously fast. If there is some liquid soap mixed in with the hydrogen peroxide, steamy foam will gush out of the container. [1:05]
tags: flame test, identifying salts, chemistry, streaming video Some elements can be identified by the colors they emit while burning. This is a quality that chemists use to identify salts, by burning them. In this video, a science teacher douses several exotic salts in methanol and ignites all of them at the same time. The results are really spectacular -- green, orange, yellow, blue, and purple flames burning side by side. [2:01] Do not do this in your parents' kitchen or you will become very good friends with the local fire department, and probably the local police as well.
Yesterday was the 1st anniversary of Blogroll Amnesty Day, originally proposed by a reasonably prominent blogger who used the occasion to relieve himself of guilt when purging his blogroll and building back up only a list of those he reads regularly. I learned via my new homies, PhysioProf and DrugMonkey that Jon Swift and Skippy have proposed this day instead as an opportunity for low-traffic bloggers to blogroll even lower-traffic bloggers to help everyone rise up in notoriety. Despite being here at ScienceBlogs for 20 months, I have managed to keep my readership to a small but select…