viernes, 1 de agosto de 2014

DRUG TEST

Portable Lab Quickly Spots Cocaine in Urine

Tue, 07/08/2014 - 7:00am
ACS
As part of a portable cocaine test that takes just minutes, this microfluidic device extracts drugs of abuse from dried urine samples. Image: ACSAs part of a portable cocaine test that takes just minutes, this microfluidic device extracts drugs of abuse from dried urine samples. Image: ACSTesting for cocaine and other drugs usually involves two steps: a quick on-site prescreen, and then a more accurate confirmatory test at a distant laboratory. This process can take days or weeks — but that’s too long in many cases where public safety is at risk. Now, researchers report development of a backpack-sized device that can perform highly accurate and sensitive tests anywhere within 15 minutes. The study appears in ACS’ journal Analytical Chemistry.
Aaron Wheeler and colleagues explain that the current two-stage system of testing urine for drugs of abuse is expensive and time-consuming. The samples also could get lost or compromised while in transport. The ideal solution, they say, is to skip the prescreening step and instead bring the lab to the site — but in an easy-to-use, portable package. Currently, when samples arrive at labs for confirmation testing, trained technicians use a “gold-standard” method, relying on sample processing, liquid chromatography and mass spectrometry to analyze them. Small versions of instruments that implement these techniques can provide results at or near lab-quality, but they haven’t been optimized and tested together as a single, portable instrument. Wheeler’s team set out to do just that.
They put together a compact system that can do all the steps — extracting drugs of abuse from urine with a microfluidic device coupled to a small mass spectrometer that can identify the substances. The backpack-sized instrument could analyze cocaine, benzoylecgonine (a metabolite of cocaine) and codeine in four samples in less than 15 minutes. The amount of cocaine they could detect was compatible with limits set by the United Nations Office on Drugs and Crime. The researchers say the device could be used for many different kinds of tests in which laboratory-quality results are needed quickly.
The authors acknowledge funding from the Natural Sciences and Engineering Council of Canada and the U.S.National Science Foundation.

Publicado por EMILIO MALAGUTI en 6:37

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GREEN CHEMICALS

The Green Seal certification is granted by the organization with that name and has a great number of members contributing with the requirements to pass a raw material or a chemical product as "green". Generally for a material to be green, has to comply with a series of characteristics like: near neutral pH, low volatility, non combustible, non toxic to aquatic life, be biodegradable as measured by oxygen demand in accordance with the OECD definition.
Also the materials have to meet with toxicity and health requirements regarding inhalation, dermal and eye contact. There is also a specific list of materials that are prohibited or restricted from formulations, like ozone-depleting compounds and alkylphenol ethoxylates amongst others. Please go to http://www.greenseal.com/ for complete information on their requirements.
For information on current issues regarding green chemicals, see the blog from the Journalist Doris De Guzman, in the ICIS at: http://www.icis.com/blogs/green-chemicals/.
Certification is an important — and confusing — aspect of green cleaning. Third-party certification is available for products that meet standards set by Green Seal, EcoLogo, Energy Star, the Carpet & Rug Institute and others.
Manufacturers can also hire independent labs to determine whether a product is environmentally preferable and then place the manufacturer’s own eco-logo on the product; this is called self-certification. Finally, some manufacturers label a product with words like “sustainable,” “green,” or “earth friendly” without any third-party verification.
“The fact that there is not a single authoritative standard to go by adds to the confusion,” says Steven L. Mack M.Ed., director of buildings and grounds service for Ohio University, Athens, Ohio.
In www.happi.com of June 2008 edition, there is a report of Natural formulating markets that also emphasises the fact that registration of "green formulas" is very confused at present, due to lack of direction and unification of criteria and that some governmental instittion (in my opinion the EPA) should take part in this very important issue.