Navigation Links
Does Aspirin Crystallize?

When people get headache, they probably reach for aspirin. What is giving researchers a headache is the question of the crystal structure of aspirin, doubting// whether there is another form on top of the long-known one! - A team of scientists from Denmark, Germany, and India seems to have solved this controversial puzzle: yes, there is a second structure—but it does not exist as a pure form.

“The two crystalline forms of aspirin are so closely related,” explains the research team of Andrew D. Bond, Roland Boese and Gautam R. Desiraju in Angewandte Chemie, “that they form structures containing domains of both crystal types.”

In 2004, computer calculations had indicated that while the long-known crystal structure of aspirin (form I) is definitely one of the most stable forms, another version might exist that is just as stable, though it had not yet been discovered—a clear challenge to researchers in the field. The difference between the proposed structures is slight: both have identical layers containing molecules grouped into pairs, but these layers are arranged differently in the two different structures.

In 2005, researchers in the USA announced the discovery of the predicted structure (form II). But was this merely an artifact?

“We can now clear this matter up,” say Bond, Boese and Desiraju, after very careful examination of aspirin crystals. “Aspirin has a tendency to crystallize with an unusual intergrown structure. The same single crystal contains domains with both arrangements lying side by side.” The distribution and ratio of the domains are variable but limited. Whereas a pure form I exists, it has so far only been possible to obtain crystals containing a maximum of 85 % form II. The ratio of the two domains within crystals produced under identical conditions seems to be roughly constant.

This discovery upends fundamental principles and requires new concepts: chemists previously understood “polymorphism” to mean that a molecule can take on one or another packing arrangement in the crystalline state; a single crystal of a specific chemical substance is either one polymorph or the other.

Aspirin is the first case in which two different “polymorphic” structures exist in one single crystal. So is aspirin polymorphic or not? Should the definition of polymorphism be updated? Such questions are not just philosophical in nature, but could have tangible implications in patent law, because each polymorph of a compound is viewed as a separate patentable substance.

Source-Eurealert
SRI
'"/>




Related medicine news :

1. What happens when Asthmatics consume Aspirin?
2. Aspirin reduces deaths
3. Aspirin and Warfarin Are Equally Effective for Stroke Prevention
4. Aspirin - a drug after one’s own hear
5. Aspirin deflated
6. Aspirin surpasses Modern Anti-clotting Drugs
7. Night Time Aspirin Regimen Found to Reduce Blood Pressure
8. Aspirin Lowers Leukemia Risk
9. Aspirin usage linked with pancreatic cancer
10. Aspirin Found To Reduce The Risk Of Colon Cancer
11. Aspirin Induced Asthma , A Little-Known Inducer
Post Your Comments:
*Name:
*Comment:
*Email:


(Date:6/26/2016)... Michigan (PRWEB) , ... June 26, 2016 , ... On ... as sponsor of the 2016 Cereal Festival and World’s Longest Breakfast Table in Battle ... honor of the city’s history as home to some of the world’s leading providers ...
(Date:6/26/2016)... ... June 26, 2016 , ... PawPaws brand pet ... product that was developed to enhance the health of felines. The formula is all-natural ... two main herbs in the PawPaws Cat Kidney Support Supplement Soft Chews ...
(Date:6/26/2016)... Orion, Clarkston, Michigan (PRWEB) , ... June 26, ... ... with respect to fertility once they have been diagnosed with endometriosis. These women ... intercourse but they also require a comprehensive approach that can help for preservation ...
(Date:6/25/2016)... ... June 25, 2016 , ... Austin residents seeking Mohs surgery services, can now ... and to Dr. Russell Peckham for medical and surgical dermatology. , Dr. Dorsey brings ... The selective fellowship in Mohs Micrographic Surgery completed by Dr. Dorsey was under the ...
(Date:6/25/2016)... ... June 25, 2016 , ... "With 30 hand-drawn hand ... project," said Christina Austin - CEO of Pixel Film Studios. , ProHand Cartoon’s ... within Final Cut Pro X . Simply select a ProHand generator and drag ...
Breaking Medicine News(10 mins):
(Date:6/24/2016)... -- Research and Markets has announced ... Applications, Technologies, Forecasts" report to their offering. ... Smart Skin, Structural Health Monitoring, Composite Smart Structures, ... involves electronic and/or electrical components and circuits that ... such as vehicle bodies or conformally placed upon ...
(Date:6/24/2016)... India , June 24, 2016 ... Needles Market by Type (Standard Pen Needles, Safety Pen ... Therapy (Insulin, GLP-1, Growth Hormone), Mode of Purchase (Retail, ... by MarketsandMarkets, This report studies the market for the ... expected to reach USD 2.81 Billion by 2021 from ...
(Date:6/23/2016)... 2016 Research and Markets has announced ... Forecast to 2022" report to their offering. ... the patients with kidney failure, it replaces the function of ... patient,s blood and thus the treatment helps to keep the ... balance. Increasing number of ESRD patients & ...
Breaking Medicine Technology: