Wednesday, May 25, 2011

IB Chemistry in Organic Chemistry, Medicine, Drugs, Option D

IB Chemistry on Medicine, Drugs, Aspirin, Analgesic , Option D
Miracle Drug, Aspirin
Analgesic drugs, Aspirin, salicylate drug acts on enzyme which produces prostaglandins to relieve pain,  antipyretic to reduce fever and anti-inflammatory properties.
Aspirin ( acetylsalicylic acid ) made from salicylic acid and acetic anhydride. 

Active ingredient from Willow Bark ( Salicylic acid ), very acidic due to OH group of phenol. Adding acetyl group changes it to Aspirin (less acidic).
1897---Aspirin synthesized by Felix Hoffmann, at Bayer.
1899-- Aspirin marketed by Bayer.
1900---First water-soluble Aspirin by Bayer.
1915---Aspirin available without prescription.
Video on History, Discovery and Nobel Prize on Aspirin 


1960---Craven's discovered Aspirin prevent platelet aggregation ( prevent blood clot )


1970---Professor Vane discovered aspirin blocks an (COX) enzyme needed for production of  hormones (prostaglandins). 


1982---Professor Vane awarded Nobel Prize, How Aspirin acts by blocking the formation of prostaglandins, giving anti inflammatory/anti pyretic and anti platelet properties.










Video on How aspirin works
.........................................................................................................................................................        

How Aspirin Works
  • Aspirin decrease production of prostaglandins by inhibiting (COX) enzyme. 
  • Works by acetylating (add acetyl gp) to a serine residue on active site of the (COX) enzyme.
  • Aspirin inhibits COX enzyme, decrease prostaglandins (hormone) production -  pain relief, reduce inflammation or swelling



                        
.....................................................................................................................................................
Good and Bad side of Aspirin from CNN
Good side
Aspirin before air travel decrease risk of deep-vein thrombosis (DVT), prevent inflammation, reduce fever, heart attacksstrokes, and blood clot.
Bad side
Aspirin increase the risk of gastrointestinal bleeding, bleeding due to its acidity



Latest discovery on Aspirin from Telegraph and Lancet
Aspirin prevent Cancer and Heart diseaseTaking a quarter of an aspirin with milk before bed could reduce your chance of dying in middle age by a tenth, the biggest study into the drug has found.
Video, latest discovery published in Lancet ( Jan 2011 )
Keywords from study/video

  • 25,570 patients on drug for average 4 years. 
  • Reduced Prostate Cancer  by 10%, Lung Cancer 30%, Bowel Cancer 40%, Throat Cancer  60%.
  • Longer you take aspirin, the greater the benefit, risks ( stomach bleeding) is "trivial" compared with the benefits. More research is required before clear conclusions can be drawn on the implications for clinical practice.
Sources from
http://www.telegraph.co.uk/health/healthnews/8184776/Aspirin-the-wonder-drug-fights-off-cancer-as-well-as-heart-disease.html
.....................................................................................................................................................
Published in Lancet (2011),  Aspirin could save thousands of lives a year from cancer alone.
Sources from
http://www.thelancet.com/journals/lancet/article/PIIS0140-6736(10)62110-1/abstract
......................................................................................................................................................
Timeline for aspirin from 400BC to Jan 2011( Lancet)
Sources from 
http://www.telegraph.co.uk/health/healthnews/8185164/Aspirin-timeline.html
......................................................................................................................................................
Aspirin Synthesis in Lab adopted from Carolina

  • Soak 2g of Willow Bark in 100 ml 95% ethanol to extract Salicylic acid.
  • After 20 mins, filter the extract (Salicylic acid)
  • Add 2 ml conc acetic acid to extract (convert it to Aspirin)
  • How to test for Salicylic acid and Aspirin.
  • Test for Salicylic acid, add 100ul of iron (III) chloride, it turn purple (phenol group)
  • Test for Aspirin, add 100ul of iron (III) chloride, it remain orange (no phenol group)
  • Test which is more acidic, Aspirin or Salicylic acid, add universal paper/indicator, Salicylic acid (more acidic), Aspirin ( less acidic ).
Thanks to all Pictures, Video and Carolina contributors for the above post

No comments:

Post a Comment

Related Posts Plugin for WordPress, Blogger...