Archive for the 'Molecule of the Week' Category

mjhaye07

A Chemical Monument

Prior to the 1800’s the chemical community had a defined line separating organic and inorganic chemistry. Organic compounds originated from living things, such as mussel tissue; and inorganic compounds originated from non-living things, such as rocks and sediment. Chemists were under the understanding that these two chemistries were separate entities, and compounds from one could not be derived from compounds of the other. In this day and age, this line is not as clearly seen as it once was. This is because of one simple compound: Urea.

Urea was first synthesized by Friedrich Wöhler, a German chemist, in 1828. What made this synthesis incredibly unique and groundbreaking was that it was an organic molecule being synthesized from inorganic starting materials. This synthesis was properly named, the Wöhler synthesis:

AgNCO (silver isocyanate)+ NH4Cl (ammonium chloride) → (NH2)2CO (urea) + AgCl (silver chloride)

From the synthesis of Urea, the line between organic and inorganic chemistry became less definitive; opening up new doors to both chemistries.

In human physiology, urea is produced by the kidneys. It’s job is to carry waste nitrogen out of the body, and also plays a role in the reabsorption of water. In agriculture and the environment, urea plays a direct role in the nitrogen cycle; allowing for the release of nitrogen in soils, which is essential for plant growth; urea is now a Urea also plays a major role in material chemistry, being a vital material of some plastic manufacturing processes, adhesives in plywood, and explosives.

So whether you are enjoying a fresh tomato from the Potsdam Co-op, an evening playing Starcraft 2 on a laptop with a plastic casing, building a treehouse with plywood flooring, or simply enjoying the fact that your body is well hydrated, we can all agree that we have Urea to thank for these, once unimaginable, components of our daily lives.

mjhaye07

Coffee, coffee. Who’s got the coffee?

College–especially SLU–is filled with a vast array of academic, community, and social networking opportunities; and with these opportunities comes a great deal of time and energy. Baring in mind that there are only 24 hours in a day (and it would take a great deal of force to slow down the rotation of the earth to change that), the average SLU student will turn to long nights hibernating in the deepest, darkest corner of Midill, cramming for their first round of chemistry exams; sacrificing hours of sleep for the understanding of ionic precipitates or the memorization of dozens of  functional groups. 12:37 am becomes a dangerous time for midnight crammers, as alertness begins to plummet, heads begin to nod-off; slowly, the library begins its transition from a respectable academic establishment to the awkwardly accurate resemblance of the front row of an 80′s Iron Maiden concert. So, as alertness begins to plummet, students routinely grab for the nearest energy drink, soda, coffee, tea, or–for the more modern, advanced taste-buds–a caramel mocha vanilla iced soy latte with dash of cinnamon and nutmeg. All of these beverages having one very important alkaloid in common; Caffeine.

Caffeine is a psychoactive stimulent drug that is popular for its temporary relief of drowsiness. It comes from the leaves and seeds of many plants; two common sources being tea leaves and coffee beans. It was first isolated in 1819 by Friedrich Ferdinand Runge and first synthesized by Hermann Emil Fischer nearly a century later. When taken in moderation, caffeine can increase the effectiveness of some common analgesics (such as aspirin or acetaminophen) and treat some respiratory diseases by acting as a bronchial dilator.  However, caffeine also has its share of negative side effects. Users often experience “the jitters” and frequent urination. Over high-dose, longterm use caffeine can sometimes lead to anxiety and sleep disorders. Caffeine is addictive, more addictive than nicotine, and dependence is easily established; throwing addicted users into a state of withdrawal without their morning cup o’ joe. Symptoms of withdrawal include headaches, irritability, stomach aches and sleeplessness.

Whatever your stance on this clever alkaloid, caffeine has played a substantial historical role in Chinese, Egyptian, Indian, British, and American culture; and a significant majority of people in North America are daily users. It has assisted students and professors alike in the long nights battling the academics, and can often be directly responsible for hours of work on lab reports, fellowship applications, and doctoral dissertations. Alas, here is to you, Caffeine. Cheers!