Fight or Flight Response – Adrenaline

It’s less than a week away from Floyd Mayweather, Jr. vs Manny Pacquiao, and the world is trembling in anticipation of the Fight to Watch for this generation! Personally, the adrenaline rush I get when I view all those promo videos (official and fan made ones) is mind blowing. Talk about butterflies in the stomach early in the morning in the absence of any threat! However, it is this very feeling that will be the subject of this post at the end of April 2015. How often are we subject to ‘threatening’ situations where our basic instinct of survival kicks in? Not so much? Well, even during sports, especially when we are put on the spot, where winning or losing a major game would fall entirely on our shoulders… that’s when Adrenaline can make or break us. Would we succumb to panic? Or would the hormone steer our heightened senses to victory?

An interesting infographic that depicts the stages of the Fight or Flight Response. The symptoms seem rather debilitating and detrimental to our survival. However, if they are honed and focused, they can bring us back to what we may have been created originally to be, not the domesticated creatures we are now.

Now, firstly we need to address the actual system itself. Our Autonomic Nervous System is a control system that acts largely unconsciously and regulates heart rate, digestion, respiratory rate, pupillary response, urination, and sexual arousal. The role of this system is mediated by the Sympathetic Nervous System, which has the main function of activating the physiological changes that occur during the fight or flight response, and the Parasympathetic Nervous System, which has the main function of activating the “rest and digest” response and return the body to homeostasis after the fight or flight response. Basically like an “ON” (norepinephrine) and “OFF” (acetylcholine) switch respectively.



Now imagine the build up to the fight on May 2nd. Neither of them will run. They’ve been wanting this for years! Once they are both in the ring, let’s take a look at what will happen.

The amygdala will trigger a neural response in the hypothalamus. The initial reaction is followed by activation of the pituitary gland and secretion of the hormone adrenocorticotropic hormone (ACTH). The adrenal gland is activated almost simultaneously and releases the neurotransmitter epinephrine. The release of chemical messengers results in the production of the hormone cortisol, which increases blood pressure, blood sugar, and suppresses the immune system (AKA ENERGY BOOST!). Epinephrine basically binds with liver cells and glucose production spikes. Additionally, the circulation of cortisol functions to turn fatty acids into available energy, which prepares muscles throughout the body for response. Catecholamine hormones, such as adrenaline (epinephrine) or noradrenaline (norepinephrine), facilitate immediate physical reactions associated with a preparation for violent muscular action.

There is a huge list of these, which includes acceleration of heart and lung action, dilation of blood vessels for muscles, pupil dilation, tunnel vision (this can be a problem, which requires focus and training to hone), loss of hearing (better known as auditory exclusion as you focus only on the sounds you need!), shaking (well DUH!), inhibition of erection (not THIS is interesting!). Also, you will have increased strength and speed! Awesome, isn’t it?

However, as with all things, nothing is free. During the reaction, the intensity of emotion brought about by the stimulus may be too high for most. Individuals with high levels of emotional reactivity may be prone to anxiety and aggression. A burst of energy such as these ones would require some form of trade off. It leaves us feeling drained after. Tired. Weak. Wet pants (for some).

Do you have problems with butterflies in the stomach? Anxiety? Stress? Unable to stand up in public or unable to solve your big problems due to fear? Then you have lost to adrenaline… rather than befriended and used it. Fear is our greatest enemy, but we were all born with the tools to combat it. Use your fear, channel it into something positive. Transcend your past self, and FIGHT!


Leave a comment

Filed under Uncategorized

What happens during Cooking? – The Maillard Reaction

There are many things in life that we take for granted. Now step back, and take a look at that sentence once again. Read it to yourself. Visualize those things that you DO realize that you’ve taken for granted. Now let me tell you (and myself) that you have severely underestimated the sheer number of things that you have taken for granted in life. As a Chemist ~ no … as a Scientist, you must strive to reduce those numbers. You must go out, and FIND OUT! Without such curiosity… I’m afraid… you do not deserve to call yourself a Scientist.

Now, take cooking for instance. You purchase ingredients, follow a series of procedural steps, maybe even put in effort in the plating of the food before serving them to yourself, your loved ones, guests, or customers even. But what actually does happen in cooking.

The Maillard Reaction occurs during cooking, and is responsible for the non-enzymatic browning of foods when cooked. Of course, it consists of a number of reactions, and can occur at room temperature, but is optimal between 140 to 165 °C (284 to 329 °F). Named after French Chemist Louis-Camille Maillard, this reaction between amino acids and reducing sugars is what gives browned foods their desirable flavor.

The crusts of most breads, such as this delicious Brioche, are golden-brown due to the Maillard reaction

Above that temperature range, caramelization and pyrolysis become more pronounced.

The carbonyl group on a sugar reacts with a protein or amino acid’s amino group (RNH3deprotonated in an alkaline environment), producing an N-substituted glycosylamine.

The glycosylamine compound generated in the first step isomerizes, by undergoing Amadori rearrangement, to give a ketosamine.

The ketosamine can react in a number of ways to produce a range of different products, which themselves can react further.

The above series of mechanisms shows how acrylamide can be formed as a by-product of the Maillard reaction (which is a known carcinogen found in foods that have been overcooked). However, there are numerous other mechanistic pathways that lead to a tremendous variety of products. It is important to note that only a small subset of these contribute to flavor and aroma.

Flavors in Cooking

The Maillard reaction is responsible for many colors and flavors in foods:

  • The browning of various meats like steak, when seared and grilled.
  • The browning and umami taste in fried onions.
  • Toast.
  • The darkened crust of baked goods like pretzels and bread.
  • The golden-brown color of French fries.
  • Malted barley, found in malt whiskey or beer.
  • Dried or condensed milk.
  • Roasted coffee.
  • Dulce de leche.
  • Maple syrup.
  • Black garlic

Click to view this infographic from Ioana Top Chef website.

When you go into the kitchen next, think of the Maillard Reaction. Think about the conditions necessary to make a delicious, stunning dish for your next meal. Do not underestimate the sheer experience and skill necessary to become a Cook. Are you ready to learn how to cook? ^_^

***Excerpts taken from Wikipedia, Google Image Search and Ioana Top Chef website.

Leave a comment

Filed under Uncategorized

Molecule of the Month – March 2015

Explosions explosions EXPLOSIONS!! I knew a Chemistry Tutor in the UK… who simply loved explosions. He studied thousands of explosive compounds, and even demonstrated a few in a Lecture on Explosive Reactions in Chemistry (with the proper safety precautions, of course!). One would think that it takes years and years of experience to perform such feats of wonder and danger. But what about those who discovered the explosives in the first place? They must have spent years, risking their lives all the way, to discover, and implement. But not all discoveries were from well-known, experienced, brilliant scientists who put everything on the line for the advancement of science.

During a fifth-grade class in 2012 conducted by a Science teacher Kenneth Boehr, ten-year-old Clara Lazen assembled a complex model using ball-and-stick model set and asked whether it was a real molecule.

Clara Lazen with her molecule in 2012

Unsure of the answer, Boehr sent a picture of the model to a chemist friend, Robert Zoellner, a Professor in Chemistry at Humboldt State University. Zoellner checked the molecule against the ‘Chemical Abstracts‘ database and confirmed that Lazen’s had a unique and previously unrecognized structure.

Professor Robert Zoellner admires a model of the new molecule in 2012

Zoellner wrote a paper on the molecule, published in Computational and Theoretical Chemistry, crediting Lazen and Boehr as co-authors.

Tetranitratoxycarbon consists of oxygen, nitrogen, and carbon, with molecular structure C(CO3N)4. As an oxygen-rich compound of carbon and nitrogen, similar to nitroglycerin, it is predicted to have explosive properties, but to be too thermally unstable for practical use.

(Notice the Schrödinger equation on the blackboard in the background!)

This is not the first time a young aspiring scientist has been a direct or indirect cause of the discovery of a new molecule, and it will not be the last. Especially to our Lower Sixth intake of 2015/2016, it falls to YOU to be innovative, to be proactive, to be brilliant and be the next Clara.

Rush headlong into Chemistry A-Level with a strong desire to EXCEL! Welcome, Lower Sixth Students, to our wonderful world ^___^

Leave a comment

Filed under Uncategorized

Molecule of the Month (April 2013) – Luminol

Ever watch CSI or any series or movies that involve forensic science? Ever wonder how they find bloodstains on the carpet or in various areas where the stain is actually so faint that you can’t see it with the naked eye? Well, Luminol is one such answer…

This molecule of the month was suggested by LJY 2013 =)
From Wikipedia, the free encyclopedia:
Molecular formula C8H7N3O2
Molar mass 177.16 g/mol
Melting point 319 °C, 592 K, 606 °F

Luminol (C8H7N3O2) is a versatile chemical that exhibits chemiluminescence, with a striking blue glow, when mixed with an appropriate oxidizing agent. It is a white to slightly yellow crystalline solid that is soluble in most polar organic solvents, but insoluble in water. Luminol is used by forensic investigators to detect trace amounts of blood left at crime scenes as it reacts with iron found in hemoglobin. It is used by biologists in cellular assays for the detection of copperiron, and cyanides, in addition to the detection of specific proteins by western blot. For analysis of an area, luminol can be sprayed evenly across the area, and trace amounts of an activating oxidant will cause the luminol to emit a blue glow that can be seen in a darkened room. The glow lasts for about 30 seconds, but the effect can be documented by a long-exposure photograph. It is important that the spraying be evenly applied to avoid creating a slanted, or biased impression, such as blood traces appearing to be more concentrated in areas which received more spray. The intensity of the glow does not indicate the original amount present, but only the distribution of trace amounts of substances left in the area.

Luminol may be synthesized by a reverse phosphorescence 2-step process. It begins from 3-nitrophthalic acid. First, hydrazine (N2H4) is heated with the 3-nitrophthalic acid in a high-boiling solvent such as triethylene glycol. An acyl substitution condensation reaction occurs, with loss of water, forming 3-nitrophthalhydrazide. Reduction of the nitro group to an amino groupwith sodium dithionite (Na2S2O4), via a transient hydroxylamine intermediate, produces luminol.


Luminol synthesis.png Luminol was first synthesized in Germany in 1902, but the compound was not named “luminol” until 1934.


Chemiluminescence of luminol

To exhibit its luminescence, the luminol must first be activated with an oxidant. Usually, a solution of hydrogen peroxide (H2O2) and a hydroxidesalt in water is used as the activator. In the presence of a catalyst such as an iron compound, the hydrogen peroxide is decomposed to form oxygen and water:

2 H2O2 → O2 + 2 H2O

In a laboratory setting, the catalyst used is often potassium ferricyanide. In the forensic detection of blood, the catalyst is the iron present inhemoglobinEnzymes in a variety of biological systems may also catalyze the decomposition of hydrogen peroxide. When luminol reacts with the hydroxide salt, a dianion is formed. The oxygen produced from the hydrogen peroxide then reacts with the luminoldianion. The product of this reaction, an organic peroxide, is very unstable and is made by losing a nitrogen, electrons going from excited state to ground state, and energy emitting as a photon. This emitting of the photon is what ultimately gives off the blue light.

Reactions leading to the chemiluminescence of luminol.

Use by crime scene investigators


In 1928, the German chemist H. O. Albrecht found that blood, among other substances, enhanced the luminescence of luminol in an alkaline solution of hydrogen peroxide. In 1936, Karl Gleu and Karl Pfannstiel confirmed this enhancement in the presence of hematin, a component of blood. In 1937, the German forensic scientist Walter Specht made extensive studies of luminol’s application to the detection of blood at crime scenes.


Luminol is used by crime scene investigators to locate traces of blood, even if it has been cleaned or removed. The investigator prepares a solution of luminol and the activator and sprays it throughout the area under investigation. The iron present in any blood in the area catalyzes the chemical reaction that leads to the luminescence revealing the location of the blood. The amount of catalyst necessary for the reaction to occur is very small relative to the amount of luminol, allowing the detection of even trace amounts of blood. The glow lasts for about 30 seconds and is blue. Detecting the glow requires a fairly dark room. Any glow detected may be documented by a long exposure photograph.


Luminol has some drawbacks that may limit its use in a crime scene investigation:

  • Luminol chemiluminescence can also be triggered by a number of substances such as copper or copper-containing chemical compounds, and certain bleaches; and, as a result, if a crime scene is thoroughly cleaned with a bleach solution, residual cleaner will cause the entire crime scene to produce the typical blue glow, effectively camouflaging any organic evidence, such as blood.
  • Horseradish sauce, via the enzyme horseradish peroxidase, catalyses the oxidation of luminol, emitting light at 428 nm (blue in the visible spectrum), which may result in a false positive.
  • Luminol will also detect the small amounts of blood present in urine, and it can be distorted if animal blood is present in the room that is being tested.
  • Luminol reacts with fecal matter, causing the same glow as if it were blood.
  • Luminol’s presence may prevent other tests from being performed on a piece of evidence. However, it has been shown that DNA can be successfully extracted from samples treated with luminol reagent.

Leave a comment

Filed under Uncategorized

Molecule of the Month (March 2013) – Ibuprofen

Reposted from Feb 2012, since not many students seemed to even realize what drugs they’ve been prescribed =)

Please send any suggestions for Molecule of the Month (April 2013) to (you WILL be credited on the post)
Please state what reasons you have for choosing the stated molecule as well.

From Wikipedia:

Ibuprofen (INN); from the nomenclature iso-butyl-propanoic-phenolic acid) is a nonsteroidal anti-inflammatory drug (NSAID) used for relief of symptoms of arthritisfever, as an analgesic (pain reliever), especially where there is an inflammatory component, and dysmenorrhea.

Ibuprofen is known to have an antiplatelet effect, though it is relatively mild and somewhat short-lived when compared with aspirin or other better-known antiplatelet drugs. In general, ibuprofen also acts as a vasodilator, having been shown to dilate coronary arteries and some other blood vessels. Ibuprofen is a core medicine in the World Health Organization‘s “WHO Model List of Essential Medicines“, which is a list of minimum medical needs for a basic healthcare system.

Ibuprofen was derived from propionic acid by the research arm of Boots Group during the 1960s. It was discovered by Andrew RM Dunlop, with colleagues Stewart Adams, John Nicholson, Vonleigh Simmons, Jeff Wilson and Colin Burrows, and was patented in 1961. Originally marketed as Brufen, ibuprofen is available under a variety of popular trademarks, including Motrin, NurofenAdvil, and Nuprin.

Chemical Structure of Ibuprofen

Athletes, the young, the old, the sick alike all use Ibuprofen. Can you recall the last time you were prescribed this chemical? Take care though… from personal experience, this drug, as well as most drugs… cause gastric discomfort 😦

Ibuprofen Tablets



Leave a comment

Filed under Uncategorized

Molecule of the Month (January 2013) – Green Fluorescent Protein (GFP)

When we were little, we’ve always wondered about things that make weird sounds, or look out of the ordinary. Now this GFP is pretty interesting. Various uses, and definitely eye catching. I found it appropriate to begin this year’s MotM with one from Biochemistry, since we will be dealing quite heavily with proteins in P4 in your A2 year. As a Chemist, you have to focus more on the actual chemical processes that accompany such molecules, and how their structure leads to their uses.

Maxim Yap C.S.
HoD Chemistry 2013

From RSC, Protein Data Bank


The green fluorescent protein, shown here from PDB entry 1gfl, is found in a jellyfish that lives in the cold waters of the north Pacific. The jellyfish contains a bioluminescent protein– aequorin–that emits blue light. The green fluorescent protein converts this light to green light, which is what we actually see when the jellyfish lights up. Solutions of purified GFP look yellow under typical room lights, but when taken outdoors in sunlight, they glow with a bright green color. The protein absorbs ultraviolet light from the sunlight, and then emits it as lower-energy green light.

So What?

You might be saying: who cares about this obscure little green protein from a jellyfish? It turns out that GFP is amazingly useful in scientific research, because it allows us to look directly into the inner workings of cells. It is easy to find out where GFP is at any given time: you just have to shine ultraviolet light, and any GFP will glow bright green. So here is the trick: you attach the GFP to any object that you are interested in watching. For instance, you can attach it to a virus. Then, as the virus spreads through the host, you can watch the spread by following the green glow. Or, you can attach it to a protein, and watch through the microscope as it moves around inside cells.


GFP is a ready-made fluorescent protein, so it is particularly easy to use. Most proteins that deal with light use exotic molecules to capture and release photons. For instance, the opsins in our eyes use retinol to sense light (see the Molecule of the Month on bacteriorhodopsin). These “chromophores” must be built specifically for the task, and carefully incorporated into the proteins. GFP, on the other hand, has all of its own light handling machinery built in, constructed using only amino acids. It has a special sequence of three amino acids: serine-tyrosine-glycine (sometimes, the serine is replaced by the similar threonine). When the protein chain folds, this short segment is buried deep inside the protein. Then, several chemical transformations occur: the glycine forms a chemical bond with the serine, forming a new closed ring, which then spontaneously dehydrates. Finally, over the course of an hour or so, oxygen from the surrounding environment attacks a bond in the tyrosine, forming a new double bond and creating the fluorescent chromophore. Since GFP makes its own chromophore, it is perfect for genetic engineering. You don’t have to worry about manipulating any strange chromophores; you simply engineer the cell with the genetic instructions for building the GFP protein, and GFP folds up by itself and starts to glow.

Engineering GFP

The uses of GFP are also expanding into the world of art and commerce. Artist Eduardo Kac has created a fluorescent green rabbit by engineering GFP into its cells. Breeders are exploring GFP as a way to create unique fluorescent plants and fishes. GFP has been added to rats, mice, frogs, flies, worms, and countless other living things. Of course, these engineered plants and animals are still controversial, and are spurring important dialogue on the safety and morality of genetic engineering.

Improving GFP

GFP is amazingly useful for studying living cells, and scientists are making it even more useful. They are engineering GFP molecules that fluoresce different colors. Scientists can now make blue fluorescent proteins, and yellow fluorescent proteins, and a host of others. The trick is to make small mutations that change the stability of the chromophore. Thousands of different variants have been tried, and you can find several successes in the PDB. Scientists are also using GFP to create biosensors: molecular machines that sense the levels of ions or pH, and then report the results by fluorescing in characteristic ways. The molecule shown here, from PDB entry 1kys, is a blue fluorescent protein that has been modified to sense the level of zinc ions. When zinc, shown here in red, binds to the modified chromophore, shown here it bright blue, the protein fluoresces twice as brightly, creating a visible signal that is easily detected.

 Exploring the Structure

You can take a close look at the chromophore of GFP in the PDB entry 1ema. The backbone of the entire protein is shown here on the left. The protein chain forms a cylindrical can (shown in blue), with one portion of the strand threading straight through the middle (shown in green). The chromophore is found right in the middle of the can, totally shielded from the surrounding environment. This shielding is essential for the fluorescence. The jostling water molecules would normally rob the chromophore of its energy once it absorbs a photon. But inside the protein, it is protected, releasing the energy instead as a slightly less energetic photon of light. The chromophore (shown in the close-up on the right) forms spontaneously from three amino acids in the protein chain: a glycine, a tyrosine and a threonine (or serine). Notice how the glycine and the threonine have formed a new bond, creating an unusual five-membered ring.

This picture was created with RasMol. You can create similar pictures by clicking on the accession code above and then picking one of the options under View Structure. The chromophore is called “CRO” in this file, and it is residue number 66 in the protein chain.

Additional information on green fluorescent protein

Roger Y. Tsien (1998): The Green Fluorescent Protein. Annual Review of Biochemistry 67, pp. 509-544.

The Green Fluorescent Protein – annotation of GFP and its family relationships, available from InterPro.

Leave a comment

Filed under Uncategorized

Partition Coefficient

A new page has been added with some details on Kpc. Please go and read! Thanks =)

The page can also be accessible via the drop down menus above (under Applications – Analytical)

Please send any notes you wish to donate for publishing on this website to

Maxim Yap
HoD Chemistry 2012

Leave a comment

Filed under Analytical Chemistry, Applications of Chemistry, Chemistry, Uncategorized

Molecule of the Month (November 2012) – Varenicline

Now students, it is not a secret. Many students abuse nicotine. If you wish to clear your life of it, now is the time! There are numerous ways, but here is one pharmacological way. There are risks however, so please read carefully. Nonetheless, ENJOY this post =)

Maxim Yap
HoD Chemistry 2012

From Wikipedia, the Free Encyclopedia

Varenicline (trade name Chantix in the USA and Champix in Canada, Europe and other countries, marketed by Pfizer, usually in the form of varenicline tartrate), is a prescription medication used to treat smoking addiction. Varenicline stimulates nicotine receptors more weakly than nicotine does, that is, it is a nicotinic receptor partial agonist. In this respect it is similar to cytisine and different from the nicotinic antagonist, bupropion, and nicotine replacement therapies (NRTs) like nicotine patches and nicotine gum. As a partial agonist it both reduces cravings for and decreases the pleasurable effects of cigarettes and other tobacco products. Through these mechanisms it can assist some patients to quit smoking.

Medical uses

Varenicline is indicated for smoking cessation. It is more effective than NRTs and nicotine agonists. In a 2006 randomized controlled trial sponsored by Pfizer, after one year the rate of continuous abstinence was 10% for placebo, 15% for bupropion and 23% for varenicline.In a 2009 meta-analysis of 101 studies funded by Pfizer, varenicline was found to be more effective than bupropion (odds ratio 1.40) and NRTs (odds ratio 1.56).

A Cochrane systematic review concluded that both varenicline and bupropion improved smoking cessation. More people quit with varenicline than with bupropion, but the difference was not statistically significant.

The FDA has approved its use for twelve weeks. If smoking cessation has been achieved it may be continued for another twelve weeks.

Varenicline has not been tested in those under 18 years old or pregnant women and therefore is not recommended for use by these groups.

Adverse effects

Nausea occurs commonly in people taking varenicline. Other less common side effects include headache, difficulty sleeping, and abnormal dreams. Rare side effects reported by people taking varenicline compared to placebo include change in taste, vomiting, abdominal pain, flatulence, and constipation. In a recent meta-analysis paper by Leung et al, it has been estimated that for every 5 subjects taking varenicline at maintenance doses (1mg twice daily), there will be an event of nausea, and for every 24 and 35 treated subjects, there will be an event of constipation and flatulence respectively. Gastrointestinal side-effects are important factors compromising the compliance of varenicline.

Depression and suicide

In November 2007, the FDA announced it had received post-marketing reports that patients using varenicline for smoking cessation had experienced several serious side-effects, including suicidal ideation and occasional suicidal behavior, erratic behavior, and drowsiness. On February 1, 2008 the FDA issued an alert to further clarify its findings, noting that “it appears increasingly likely that there is an association between Chantix and serious neuropsychiatric symptoms.” It is unknown whether the psychiatric symptoms are related to the drug or to nicotine withdrawal symptoms, although not all patients had stopped smoking. The FDA also recommended that health care professionals and patients watch for behavioral and mood changes.In May 2008, Pfizer updated the safety information associated with varenicline, noting that “some patients have reported changes in behavior, agitation, depressed mood, suicidal thoughts or actions.” While it is unclear whether or not a small subgroup of people develop depression and suicidal ideation as a result of varenicline or smoking cessation itself, there is evidence that varenicline, similar to nicotine, has antidepressant properties and the use of varenicline for smoking cessation leads to a reduced rate of initiation of antidepressant pharmacotherapy.

As of July 1, 2009, the US Food and Drug Administration requires Chantix (varenicline) to carry a black box warning, the agency’s strongest safety warning, due to public reports of side effects including depression, suicidal thoughts, and suicidal actions.

Cardiovascular disease

On June 16, 2011, the FDA issued a safety announcement that Chantix may be associated with “a small, increased risk of certain cardiovascular adverse events in patients who have cardiovascular disease.”

On July 4, 2011, four scientists published a review of double-blind studies in the Canadian Medical Association Journal. They found that varenicline has increased risk of serious adverse cardiovascular events compared with placebo.

Mechanism of action

Varenicline is a partial agonist of the α4β2 subtype of the nicotinic acetylcholine receptor. In addition it acts on α3β4 and weakly on α3β2 and α6-containing receptors. A full agonism was displayed on α7-receptors.

Acting as a partial agonist varenicline binds to, and partially stimulates, the α4β2 receptor without producing a full effect like nicotine. Thus varenicline does not greatly increase the downstream release of dopamine. Due to its competitive binding on these receptors, varenicline blocks the ability of nicotine to bind and stimulate the mesolimbic dopamine system, akin to the action of buprenorphine in the treatment of opioid addiction.

Varenicline also acts as an agonist at 5-HT3 receptors, which may contribute to mood altering effects of varenicline.


Most of the active compound is excreted renally (92–93%). A small proportion is glucuronidated, oxidated, N-formylated or conjugated to a hexose. The elimination half-life is about 24 hours.


Varenicline was discovered at Pfizer through the research aimed at modifying the structure of cytisine.

Varenicline received a “priority review” by the U.S. Food and Drug Administration (FDA) in February 2006, shortening the usual 10-month review period to 6 months because of its demonstrated effectiveness in clinical trials and perceived lack of safety issues. The agency’s approval of the drug came on May 11, 2006. August 1, 2006, varenicline was made available for sale in the United States and on September 29, 2006, was approved for sale in the European Union.

Leave a comment

Filed under Applications of Chemistry, Chemistry, Design and materials, General

Welcome to our Cohort 2 Students!

Happy Leap Year 29th February 2012 everyone! With the start of March comes a new beginning for our Cohort 2 Chemistry students. Start off fresh and on the ball, and you will end up with better results than you expected! On behalf of the PTEK Chemistry Department, I bid you all welcome, and wish you all the very best in your endeavors in A-Level Chemistry.

Do NOT underestimate this subject (as well as any other subject for that matter), and you will be well on your way towards a successful future.

Before we begin anything, please take the time to read about Safety in the Laboratory. It is imperative that we behave as scientists in the science laboratory. For more information, here is the full document regarding Safety!

Please download a copy of the CIE 9701 A-Level Chemistry Syllabus for your reference. I advise that you use this as a checklist for your revision purposes. Put a tick after each time you have been delivered material by your tutors, and then a second tick when you have understood the concept. That way you will be able to plan your revision well in the future. Of course, by the time you see 3 ticks on every objective in the syllabus, you should be ready for almost ANY question that CIE can throw your way. Also, you should print out a copy of the Practical Assessment (Qualitative Analysis) Notes as they will be used in EVERY Practical Session. They can be found on pages 69-70 of the Syllabus.

We INSIST that you all visit this website often to keep yourself up to date with anything involving PTEK Chemistry. Resources will be put up as we go along, maybe some worksheets, mark schemes and please take note at the very bottom of this page… the COUNTDOWN to your First APR. =) They should begin roughly around the 9th of April, 2012.

Being prepared is half the battle won!

Maxim Yap
HoD Chemistry 2012

Leave a comment

Filed under General

Molecule of the Month (March) – Ibuprofen

From Wikipedia:

Ibuprofen (INN); from the nomenclature iso-butyl-propanoic-phenolic acid) is a nonsteroidal anti-inflammatory drug (NSAID) used for relief of symptoms of arthritis, fever, as an analgesic (pain reliever), especially where there is an inflammatory component, and dysmenorrhea.

Ibuprofen is known to have an antiplatelet effect, though it is relatively mild and somewhat short-lived when compared with aspirin or other better-known antiplatelet drugs. In general, ibuprofen also acts as a vasodilator, having been shown to dilate coronary arteries and some other blood vessels. Ibuprofen is a core medicine in the World Health Organization‘s “WHO Model List of Essential Medicines“, which is a list of minimum medical needs for a basic healthcare system.

Ibuprofen was derived from propionic acid by the research arm of Boots Group during the 1960s. It was discovered by Andrew RM Dunlop, with colleagues Stewart Adams, John Nicholson, Vonleigh Simmons, Jeff Wilson and Colin Burrows, and was patented in 1961. Originally marketed as Brufen, ibuprofen is available under a variety of popular trademarks, including Motrin, Nurofen, Advil, and Nuprin.

Chemical Structure of Ibuprofen

Athletes, the young, the old, the sick alike all use Ibuprofen. Can you recall the last time you were prescribed this chemical? Take care though… from personal experience, this drug, as well as most drugs… cause gastric discomfort 😦

Ibuprofen Tablets




Filed under General, Organic Chemistry