Chemistry

In the fight against HIV, microbicides, which are chemical compounds applied topically to the female genital tract to protect against sexually transmitted infections, are touted as an alternative to condoms. There's just one problem. They don't work outside a petri dish. Clinical trials using microbicides have failed and a new study from the Gladstone Institutes and the University of Ulm finds that this may be due to the primary mode of transportation of the virus during sexual transmission, semen. "We think this may be one of the factors explaining why so many drugs that efficiently…

In hydraulic fracturing - fracking - a mixture of sand, water and chemicals is injected into deep wells to release fossil fuels. This has led to environmental corporation claims that the reduced emissions from natural gas are being offset environmentally by surfactants. A surfactant is basically a detergent. It reduces the surface tension between water and oil, allowing for more oil to be extracted from porous rock underground.   A University of Colorado Boulder study has found there is little to fear. The surfactant chemicals found in samples of fracking fluid collected…

The U.S. Food and Drug Administration (FDA) is warning Whole Foods customers not to consume a line of organic raw almonds due to elevated levels of hydrogen cyanide (prussic acid/formonitrile - chemical formula HCN). Hydrogen cyanide is a natural toxic chemical that interferes with oxygen in our organs so it can quickly be fatal, but even in smaller exposure can be damaging to the central nervous system, the cardiovascular system and the pulmonary system. That's why it has been synthesized for use in chemical warfare.  It isn't just in plants and organic food, it is also created by…

Laundry detergent pods became popular 2010, because they are more precise than liquids or powder. Are they more dangerous than liquids or powder? A new paper from researchers at Nationwide Children's Hospital is sounding the alarm.   Data for this study came from the National Poison Database System, the most comprehensive and accurate database available for investigation of poisonings in the United States. The study was conducted by researchers at the Center for Injury Research and Policy and the Central Ohio Poison Center, both at Nationwide Children's Hospital, and The Ohio State…

I'll have a clean cage with a side of fertility issues. Mouse image via www.shutterstock.com By Anne-Marie Hodge, University of Wyoming Mice possess a notable talent: they are excellent at making more mice. Their ability to reproduce at a breakneck pace is one reason they are often used as experimental research subjects. Thus, when Dr. Terry Hrubec realized that the mice in her veterinary research lab at Virginia Tech were showing sudden and dramatic declines in reproductive success, she knew she had a problem. After combing through the literature for possible explanations, Hrubec discovered…

An organic compound called limonene provides the pleasant smell of cleaning products and air fresheners but some byproducts of these sweet-smelling compounds could be adding to the air while they remove germs and odors. By cleaning your house, you could be adding smog and ozone to it.  Secondary organic aerosols (SOAs) are microscopic particles created when ozone reacts with volatile organic gases such as limonene –the chemical name for the smell of oranges- or its cousin α-pinene, which is part of the smell of pine trees. Outdoors, this reaction happens all the time. It drives the…

Researchers on an international team recently showed a way to quickly and reliably find the fastest way through a city maze. But rather than using a satellite navigation system, they used chemistry. It needs a little work before UPS can use it, since the chemical processor was in alkaline liquid, bit it is intriguing proof of concept. They used the laws of physical chemistry to do “chemical computing.” They mixed a gel with acid at the exit of a labyrinth filled with alkaline liquid. In a short time, the acid spreads through the alkaline maze, although the majority of it remains together with…

There are four factors to making the perfect cup of coffee. Credit: Andy Ciordia/Flickr, CC BY-NC-ND By Don Brushett It’s hard to get a bad coffee these days. Plenty of baristas have fine-tuned the process of making espresso, but really there are only a handful of variables they can control: coarseness of the grind temperature of the extraction extraction time the all-important coffee-to-water ratio. Coffee roasters and barista schools have produced many impressively complex charts plotting grams of coffee against volume of water overlaid with concentration and yield. In the middle is the…

Bisphenol A (BPA) is a chemical that is used in a variety of consumer products, such as water bottles, dental composites and resins used to line metal food and beverage containers.  It is also used in thermal paper cash register receipts and a new paper finds that is cause for concern. BPA has not been found to be harmful by the Centers for Disease Control, they say levels from all sources is 1/1000th safe levels for the US, the EU and Canada, but it is controversial due to publicity by environmental groups and the guilt-by-association taint of endocrine disruption.  The FDA agrees…

Frying in oil is one of the world's most popular ways to prepare food — chicken and French-fried potatoes are staples but even candy bars and whole turkeys have joined the list of deep-friend goodness.  Lots of oil make health claims but there is a whole range of physical, chemical and nutritional properties that can degrade oil quality when heated so a paper in the Journal of Agricultural and Food Chemistry  tested four different refined oils — olive, corn, soybean and sunflower — and reused the oil 10 times to determine which is truly the best. The answer: Olive oil.…