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:6/25/2016)... ... ... closing of Bruton Memorial Library on June 21 due to a possible lice infestation, as ... of head lice: the parasite’s ability to live away from a human host, and to ... one in the event that lice have simply gotten out of control. , As lice ...
(Date:6/25/2016)... ... ... As a lifelong Southern Californian, Dr. Omkar Marathe earned his Bachelors in ... School of Medicine at UCLA. He trained in Internal Medicine at Scripps Green Hospital ... at the UCLA-Olive View-Cedars Sinai program where he had the opportunity to train in ...
(Date:6/25/2016)... ... June 25, 2016 , ... Conventional wisdom preaches the ... In terms of the latter, setting the bar too high can result in disappointment, ... just slow progress toward their goal. , Research from PsychTests.com reveals ...
(Date:6/24/2016)... (PRWEB) , ... June 24, 2016 , ... June 19, ... the dangers associated with chronic pain and the benefits of holistic treatments, Serenity ... who are suffering with Sickle Cell Disease. , Sickle Cell Disease (SCD) is a ...
(Date:6/24/2016)... Fla. (PRWEB) , ... June 24, 2016 , ... Global ... Trend magazine’s 2016 Legal Elite. The attorneys chosen by their peers for this recognition ... Florida. , Seven Greenberg Traurig Shareholders received special honors as members of this year’s ...
Breaking Medicine News(10 mins):
(Date:6/26/2016)... 2016 One of Australia,s successful ... of a new biotechnology company, Noxopharm Limited [ABN 50 608 966 ... and to list on the ASX. Noxopharm is a ... enter a Phase 1 clinical study later this year. ... of the biggest problems facing cancer patients - the ability of ...
(Date:6/26/2016)... 2016 Jazz Pharmaceuticals plc (Nasdaq: ... Hart-Scott-Rodino Antitrust Improvements Act of 1976, as amended ("HSR"), ... Inc. ("Celator"; Nasdaq: CPXX ) expired effective ... As previously announced on May 31, 2016, ... agreement under which Jazz Pharmaceuticals has commenced a tender ...
(Date:6/26/2016)... -- VMS Rehab Systems, Inc. ( www.vmsrehabsystemsinc.com ) reported today ... to build a strong and stable market for trading ... the OTC Markets-pink current trading platform. Explains ... seeing an anomaly in market trading activities that may ... Company, but shareholders and market players as well. I ...
Breaking Medicine Technology: