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:8/18/2017)... ... August 18, 2017 , ... As an industry leader, ... webinar, they will present the line of epMotion automated liquid handling system. This ... can automate everyday pipetting tasks. , Ideal for scientists and lab technicians with ...
(Date:8/18/2017)... ... August 18, 2017 , ... Hernandez Insurance Agencies, ... communities throughout the greater DC region, is inaugurating a “New Leash On Life” ... animals and training them to be companions for veterans in need. , The ...
(Date:8/18/2017)... (PRWEB) , ... August 18, 2017 , ... ... and financial planning services to communities in east Texas, is launching a regional ... Tumor Foundation. , Founded in 1991, the Pediatric Brain Tumor Foundation (PBTF) has ...
(Date:8/18/2017)... Saint John, IN (PRWEB) , ... August 18, 2017 , ... ... services to communities in northwest Indiana, is campaigning in support of Campagna Academy in ... Formerly referred to as the “Hoosier Boys’ Town of Indiana,” Campagna Academy is a ...
(Date:8/18/2017)... ... ... The Golseth Agency, a Texas based insurance management and financial planning assistance provider ... organized to provide support to Christina Upchurch and her two children after the loss ... returned from out of town to find her husband passed away and their home ...
Breaking Medicine News(10 mins):
(Date:7/27/2017)... July 27, 2017  West Pharmaceutical Services, Inc. (NYSE: ... for the second-quarter 2017 and updated financial guidance for ... Second-Quarter 2017 Highlights Reported net sales ... the prior-year quarter. Net sales at constant currency (organic) ... EPS was $0.51, compared to $0.60 in the prior-year ...
(Date:7/26/2017)... SINGAPORE , July 27, 2017  Radium Medical Aesthetics, a ... LASEMD, designed to delay aging by effectively addressing several skin conditions ... the skin to become rougher and more fragile. The skin becomes ... the unavoidable exposure to the harmful UV rays from the sun ... hyperpigmentation. ...
(Date:7/26/2017)... YORK , July 26, 2017 The ... Annual Prix Galien USA Award Nominees. ... the Prix Galien Award recognizes outstanding biomedical and technology product ... To qualify, each candidate must be U.S. ... last five years and demonstrate tremendous potential to impact human ...
Breaking Medicine Technology: