The Role Of Glycogen In Body

Glycogen is the body’s stored energy, with the biggest storage site in the liver and the balance in the muscles. When broken down in the body, glycogen is transformed into glucose. A great deal of research has been done on glycogen and its role in the body ever since it was recognized as a critical part of the body’s energy storage system.

Glycogen is stored glucose. After eating, the body takes the glucose it needs to function for movement and brain power and stores the rest as glycogen in the liver and muscles, to be used at a time when it is needed. This is called glycogenesis. In humans, the body can store around 2,000 kilocalories of glycogen at any given time. When people eat, levels are refreshed, with the body working to keep levels as stable as possible so that there is a steady supply of energy.

After a few hours without refueling by food consumption, the body’s glycogen stores are exhausted and yet the nervous system continues to demand it. Lower glycogen stores result in sluggish mental and physical reactions, making it difficult to concentrate and respond to emergencies.

When blood sugar goes down, glucagon (a hormone) is secreted which turns glycogen into a fuel source (blood sugar), called glycogenolysis. When muscles contract, glycogen is broken down into glucose and the glucose is used as energy. After exercise, the body will replace its glycogen stores as soon as you eat something. If glycogen and fat reserves are depleted, the body begins to break down protein and use it as a fuel source.

Athletes can experience a situation in which their glycogen reserves are depleted. This occurs in endurance activities, in which the body slowly uses up its supplies over the course of an event like a marathon. When this point is reached, it is sometimes referred to as “hitting the wall,” thanks to the strain it puts on the body.

Expert Insight
Twenty-five percent of the body’s glycogen is stored in the liver, with 75 percent in the skeletal muscles and trace amounts in the heart and other tissues. Care must be taken not to undereat the foods needed in order to synthesize glycogen in the body and also not to overeat sugary food, as excess glycogen and glucose will be stored as fat. Balancing out complex carbohydrates that have a low glycemic index to simple carbohydrates is an important consideration when planning meals.

If you begin to get the mid-afternoon slumps, try eating a piece of cheese, a few grapes and whole wheat crackers. The fiber will be good for you and the fruit will give you that little bit of a glucose boost that you need.

Storing gas in vegetables

A team led by the University of Liverpool and South China University of Technology is investigating the viability of storing gas in ‘bioclathrates’ formed from fungi and vegetables.

Gas storage, both short and long term, is an expensive and energy intensive process, with liquefaction and compression into porous sorbents the two methods under consideration.

Inspired by biomimetic approach
But Professor Andrew Cooper, from the University’s Department of Chemistry, and Weixing
Wang, from South China University of Technology, inspired by the biomimetic approaches to heavy metal storage and the ability of natural structures to facilitate gas transport, decided to delve deeper.

Clathrate hydrates are a chemical compound of water and gas, where the gas molecules are trapped inside a crystalline cage of ordered, hydrogen bonded water molecules. They can form with a large number of low molecular weight gases, such as methane and CO2. But they form very slowly, with high pressures required to force the gas into the water, and low temperatures to form the ice-like structures, making it debatable that the process is more energy efficient than other methods.

Professor Cooper and his team decided to investigate the ability of biological structures, such as fungi and vegetables, to increase the formation rate of clathrate storage without introducing complex mixing technologies.

Mushrooms and aubergines

They found that different biological structures offer significantly varied levels of gas uptake. Mushrooms and aubergines(also known as eggplants) showed most potential, while tomatoes were unable to achieve clathrate formation.

Prof Andy Cooper said: “Clearly, it would not be desirable to use high-value food materials for gas transport, but there might be abundant, non-food biomass that can do the same job. This work is currently a long way from practical application, but we hope that it will inspire other scientists to think about this problem in new ways. There is an enormous variety of biomass on the planet, we limited our initial search to the local supermarket.”

Mining Ancient Ores for Clues to Early Life

An analysis of sulfide ore deposits from one of the world’s richest base-metal mines confirms that oxygen levels were extremely low on Earth 2.7 billion years ago, but also shows that microbes were actively feeding on sulfate in the ocean and influencing seawater chemistry during that geological time period.

The research, reported by a team of Canadian and U.S. scientists in Nature Geoscience, provides new insight into how ancient metal-ore deposits can be used to better understand the chemistry of the ancient oceans — and the early evolution of life.

Sulfate is the second most abundant dissolved ion in the oceans today. It comes from the “rusting” of rocks by atmospheric oxygen, which creates sulfate through chemical reactions with pyrite, the iron sulfide material known as “fool’s gold.”
The researchers, led by PhD student John Jamieson of the University of Ottawa and Prof. Boswell Wing of McGill, measured the “weight” of sulfur in samples of massive sulfide ore from the Kidd Creek copper-zinc mine in Timmins, Ontario, using a highly sensitive instrument known as a mass spectrometer. The weight is determined by the different amounts of isotopes of sulfur in a sample, and the abundance of different isotopes indicates how much seawater sulfate was incorporated into the massive sulfide ore that formed at the bottom of ancient oceans. That ancient ore is now found on Earth’s surface, and is particularly common in the Canadian shield.

The scientists found that much less sulfate was incorporated into the 2.7 billion-year-old ore at Kidd Creek than is incorporated into similar ore forming at the bottom of oceans today. From these measurements, the researchers were able to model how much sulfate must have been present in the ancient seawater. Their conclusion: sulfate levels were about 350 times lower than in today’s ocean. Though they were extremely low, sulfate levels in the ancient ocean still supported an active global population of microbes that use sulfate to gain energy from organic carbon.

“The iron sulfide ore deposits that we looked at are widespread on Earth, with Canada and Quebec holding the majority of them,” says Wing, an associate professor in McGill’s Department of Earth and Planetary Science. “We now have a tool for probing when and where these microbes actually came into global prominence.”

“Deep within a copper-zinc mine in northern Ontario that was once a volcanically active ancient seafloor may not be the most intuitive place one would think to look for clues into the conditions in which the earliest microbes thrived over 2.7 billion years ago,” Jamieson adds. “However, our increasing understanding of these ancient environments and our abilities to analyze samples to a very high precision has opened the door to further our understanding of the conditions under which life evolved.”

The Triumph and tragedy Of Montreal

You may have heard of the dangerous hole in the ozone layer. Have you wondered how it came to be? And how countries are trying to plug it? That is the story of the Montreal Protocol.

The disaster of CFCs
We all use refrigerators. The most important part of it is the refrigerant – the
chemical that takes the heat away from it and leads to cooling. Up to the 1920s, most refrigerants were either explosive or toxic. In 1930, Thomas Midgley and Charles Kettering discovered that chlorofluorocarbons (CFCs) did the job very well, and were safe and non-explosive.

Soon, CFCs were being manufactured on a massive scale as many other uses for them were found. However, safe disposal procedures were not instituted, and many tones of CFCs escaped into the atmosphere. As you may already know, CFCs react with ozone in the presence of sunlight and rob us of our protection from cancer-causing UV rays.

Countries begin to act
While some countries had begun phasing out CFCs, there would be a real impact only
if all countries cooperated. A conference of 20 countries was held in Vienna immediately after the ozone hole was revealed. Discussions then spread over the next four years, to decide how much each country would agree to do to eliminate CFCs. The final agreement was made at Montreal on September 16, 1987 (now celebrated as World Ozone Day), because of which it is called the ‘Montreal Protocol’. The treaty aimed to eliminate global production of CFCs by 1996, so that the ozone hole would recover by 2050.

Unfortunately, the Protocol was fiercely resisted by many industries and poor countries. CFCs were cheap to manufacture, and replacing them was costly. September 16th is celebrated as World Ozone Day to commemorate the signing of the Montreal Protocol.

The triumph of will
However, governments recognized the seriousness of the problems. They passed tough
laws which forced companies to abandon the use of CFCs. In 1992, the ‘Multilateral Fund’ was created, by which rich countries would provide money to poorer countries to switch to CFC alternativTriumph and tragedyes. Today the Protocol has been signed by all the 196 member countries of the United Nations.

The Protocol has provided for the monitoring of CFCs in the atmosphere regularly. The good news is that levels of all CFCs have stopped increasing, and levels of some have actually reduced. As of 1994, CFCs are no longer produced, except for special applications for which an alternative has yet to be found. In 1995, Rowland and Molino were given the Nobel Prize for Chemistry.

It shows that when we put our heads together, the worst of our problems can be solved. In fact, Kofi Annan, the former secretary general of the United Nations called the Montreal Protocol “the single most successful international agreement to date”!

Greenland Ice Sheet Carries Evidence of Increased Atmospheric Acidity

Research has shown a decrease in levels of the isotope nitrogen-15 in core samples from Greenland ice starting around the time of the Industrial Revolution. The decrease has been attributed to a corresponding increase in nitrates associated with the burning of fossil fuels.

However, new University of Washington research suggests that the decline in nitrogen-15 is more directly related to increased acidity in the atmosphere.
The increased acidity can be traced to sulfur dioxide, which in the atmosphere is transformed to sulfuric acid, said Lei Geng, a UW research associate in atmospheric sciences. Following the Industrial Revolution, sulfur dioxide emissions increased steadily because of coal burning.

“It changes the chemical properties of the lower troposphere, where we live, and that can have a lot of consequences,” Geng said. He presented his findings on Dec. 7 at the fall meeting of the American Geophysical Union in San Francisco.
The gradual buildup of acidity in the atmosphere over a century got a boost around 1950 with a sharp increase in nitrogen-oxygen compounds, referred to as NOx, mainly produced in high-temperature combustion such as occurs in coal-fired power plants and motor vehicle engines. NOx is easily converted to nitric acid in the atmosphere, further increasing the acidity.

NOx carries a chemical signature — the abundance of nitrogen-15, one of two nitrogen isotopes — which changes depending on the source. That means it is possible to distinguish NOx that came from a forest fire from NOx produced as a result of lightning, soil emissions, car exhaust and power plant emissions. The level of nitrogen-15 can be measured in nitrates that formed from NOx and were deposited in ice sheets such as those in Greenland.

Current evidence indicates NOx from coal-fired power plant and motor vehicle emissions likely carries more nitrogen-15 than NOx produced by natural sources, so nitrogen-15 levels in deposited nitrate could be expected to go up. However, those levels actually went down in the late 1800s, following the Industrial Revolution, Geng said. That’s because increasing sulfuric acid levels in the atmosphere triggered chemical and physical processes that allowed less nitrogen-15 to remain in vaporized nitrate(NO3, the CAS number is 14797-55-8 or 84145-82-4), which can be carried to remote places such as Greenland. The growing acidity in the atmosphere was occurring decades before acid rain was recognized as a threat, particularly in industrial areas of North America.

“We’ve seen a huge drop in sulfate concentrations since the late 1970s,” Geng said. “By 2005, concentrations had dropped to levels similar to the late 1800s.” Ice core data show nitrate levels have stabilized during that time, he said, because while emission levels from individual vehicles might have decreased substantially, the number of vehicles has increased significantly.

Why green chemistry is necessary

After you finishing doing with your chemistry experiments at school, what would you do? You may pour the chemicals down the sink. Now imagine thousands of factories doing that, and you’ll realize there will be a problem. Luckily a solution is coming about – green chemistry.

Science and Sustainability
Every day, millions of tones of hazardous chemicals are buried underground, dumped into rivers, lakes and seas or spewed into the air. The aim of green chemistry is to develop new methods that reduce and prevent pollution.

Paul Anastas and John C. Warner of the U.S. Environmental Protection Agency laid out the Twelve Principles of green chemistry. They are:

  1. It is better to prevent waste than to treat it after it is formed.
  2. Methods for making new chemicals should be designed so that all the materials used in the reaction become part of the final product.
  3. These methods should use and generate substances that possess zero danger to human health and the environment.
  4. ‘Green’ chemical products should work as well as others, and still be less toxic.
    The use of ‘auxiliaries’ i.e. substances like solvents, purification agents etc., should be made unnecessary; or harmless substances should be used.
  5. ‘Green’ reactions should minimize the need for conditions like high pressure or low temperature. Instead, they should be possible at normal temperature and pressure.
  6. A raw material should be renewable (e.g. like biogas) rather than deplete the natural resource (like coal).
  7. A ‘green’ process should reduce the number of steps, and therefore the need for intermediate products.
  8. Reagents that can be used again and again (called catalytic reagents) should be used instead of those that are needed in large quantities (stoichiometric reagents).
    A ‘green’ chemical product should be designed so that when it is not needed, it can break down into harmless chemicals.
  9. A ‘green’ process should allow for monitoring and control in order to prevent the formation of hazardous substances.
  10. A ‘green’ substance or process should not carry a risk for a chemical accident, such as a fire or leak of dangerous substance.

You can see that green chemistry has many challenges ahead of it. To encourage scientists, many countries offer prizes for new technologies that follow these principles. These include the US, UK, Australia, Japan and Canada. In India, the pioneer of Green Chemistry is the Tata Chemicals Innovation Centre in Pune.

Advances in Green Chemistry
A few technical advancements have been made so far. One of the most important is the use of ‘dry media reactions’. In this, the reagents are embedded in a dry material, rather than dissolved in a solvent. The matrix can be recycled after the reaction is over, thus eliminating what would otherwise have been a huge waste of solvent.

A company called NatureWorks has developed a new packaging material called polylactic acid (PLA,its CAS number is 26100-51-6) using the above principles. The advantage of PLA is that it is not wasteful to make, and can be recycled. If you forget to recycle it and throw it away instead, it is degraded by bacteria into harmless substances.

How can you do?
You too, can make a contribution to green chemistry by taking a small pledge, when you do your chemistry practicals. Use as little of the chemicals you need; Don’t pour hazardous substances down the sink, dispose it through the correct methods; Work out the reaction carefully in your notebook before you do it in the lab; If your reaction needs heating or cooling, do it for the minimum time needed; If you follow the pledge, you’ll not only have a greener experience, but a safer and more scientific one too.

Tyrian Purple of Kings

Nowdays, clothes of different colours cost almost the same. But did you know that a few generations ago, the cost depended on the colour of the cloth? This was because dyes were expensive to obtain. Tyrian Purple was a dye so expensive that only kings could afford it!

Born in the Purple
Tyrian Purple (also called Royal Purple) dyes clothes a deep purple shade. In ancient times, it was extracted from the Mediterranean sea snail (Murex brandaris).

After the snails are fished from the sea, the dye-bearing vein is extracted and crushed. For every hundred pounds of the juice, 20 ounces of salt are added, and left for three days. It is then set to boil slowly in vessels of tin [or lead], to concentrate the dye, for upto ten days. Then the cloth to be dyed is immersed into the boiling mixture. The boiling is continued until the cloth is dyed to the satisfactory shade. Red shades are considered inferior to blackish ones. Finally the cloth is left to soak until it has fully imbibed the colour.

Worth its weight in silver
It is said that it took 12,000 snails to produce just 1.4 grams of this dye. Because of this, it was so expensive, that the historian Theopompus reported that, “Purple for dyes fetched its weight in silver”. Yet, there was a craze for this dye as a status symbol. In fact the Emperors of Byzantium made a law forbidding anybody from using it except themselves. The expression ‘born in the purple’ rose from this practice.

Dyes ancient, Dyes modern
Until modern times, all dyes were made in a similar manner. For example, cochineal (which gives a crimson colour) was made from the scale insect Kermes vermilio. To make one pound of dye, 70,000 insect bodies were boiled, dried, powdered and boiled again in ammonia. The red dye was then extracted by filtration and precipitation by alum. Indigo was extracted from leaves of the indigo plant (Indigofera tinctoria). Leaves were soaked in water and fermented to produce the blue dye. This was then precipitated using lye (sodium hydroxide), dried and powdered. To make just a 100 g of dye, you’d need to grow 37 square metres of crop – that’s why it was also called ‘Blue Gold’!

In 1909, Paul Friedlander discovered the chemical structure of Tyrian Purple (now called 6,6-dibromoindigo). But by then, the nature of the dye industry had completely changed. New dyes were now being made from the by-products of coal extraction. The first of these was mauveine, synthesised by the British chemist William Henry Perkin from coal tar in 1856. As these dyes were cheaper and offered a wider range of colours, the need for natural dyes disappeared. And that’s why the clothes we buy today and no longer priced on the basis of colour!

Keeping ship hulls free of marine organisms

Special underwater coatings prevent shells and other organisms from growing on the hull of ships—but biocide paints are ecologically harmful. Together with the industry, researchers have developed more environmentally-friendly alternatives.

Every year, this so-called biofouling causes economic losses of billions of Dollar. Biological growth on the underwater surface promotes corrosion. The deposits increase the roughness of the hull below the waterline which has a braking effect as the ship travels. Depending on the roughness of the basified bio layer, the consumption of fuel can increase by up to 40 percent. In the case of a large container ship this can result in additional annual costs of several millions.

A good news is that researchers have developed a more ecologically-friendly alternative. “The electrochemically active coating system produces regularly changing pH values on the surface of the hull. This effectively prevents colonization without having to use any biocides”, explains Professor Manfred Füting of the IWM in Halle who is coordinating the project.

Large area electrodes were painted on an isolating primer coating. The electrochemical active layer based on a sol-gel paint of NTC (nano tech coating gmbH), which was modified by electrically conductive particles. A current density of lower than 0,2 mAcm-2 generates enough pH stress near the surface of the hull to prevent the growing on of any barnacles, shells and algae The electric current is supplied by a photovoltaic module or by the land based power grid.

All the countermeasures used to date have considerable drawbacks: Cleaning the hull by sandblasting in a dry dock removes also the painted coating and can only be used every three to five years. There are effective hull coatings preventing the growing of adhering bio layers, but in most cases by ecotoxic biocides. Both copper ions and synthetic biocides accumulate in the coastal water and in the sediments. For this reason the particularly toxic tributyltin (TBT) is banned since 2008 and the currently preferred and still permitted copper oxide containing coatings are to be replaced by non-toxic alternatives in the foreseeable future.

Tests with the first prototypes at the Barth shipyard were promising: differently coated and electrochemically active and passive large areas are currently tested to prove their long-term stability against hydrodynamic stress and efficiency to prevent adherence and growth of bio layers. To achieve the real applicability of an economically competitive and ecofriendly antifouling system follow-up projects are planned: “They will mainly involve improving the technical applicability and optimization of our electrochemical antifouling system, which then could be applied on ship hulls for at least 3 to 5 years”, states Futing.

Antiseptic Products In Healthcare

Did you wash your hands with soap before sitting down for dinner?You may forget it and can’t wait to eat foods. But did you know that washing hands is so important, it actually saves lives?

Ignaz Semmelweiss  – The saviour of mothers
Ignaz Semmelweiss was a doctor at the Vienna General Hospital from 1846 to 1865. He was greatly worried that too many women died during childbirth. After careful observations, he discovered that doctors who handled different patients accidentally caused infections in women who came to deliver babies. He started the practice of making all doctors and nurses wash their hands in chlorinated lime (now called calcium hypochlorite). Because of this, the rate of deaths declined sharply.

Semmelweiss developed a theory that there were tiny ‘particles’ that could be transmitted from body to body and caused diseases. However, no one believed him. Because of this, his practice was not adopted outside his own hospital.

Ignaz Semmelweiss first started the practice of making all doctors and nurses wash their hands before and after surgery.

Joseph Lister – the founder of antiseptic surgery
A doctor at the Glasgow Royal Infirmary called Joseph Lister  had similar thoughts to what Semmelweiss had. He wondered whether germs could be killed by chemical solutions. After a few experiments, he discovered that carbolic acid (now called phenol) was effective. He used it to clean surgical tables and instruments before and after surgery. Due to this, the survival of patients was greatly increased. Soon, carbolic soap was mandatory in all hospitals.

So why did Lister succeed while Semmelweiss did not?

The germ theory and modern antiseptics
Semmelweiss failed because he could not prove his theory. That proof came only in 1864, when Louis Pasteur demonstrated that microscopic bacteria caused diseases. This is now called the ‘germ theory of disease’. Pasteur’s published his discovery in a famous science journal that was read all over the world. When Joseph Lister came across this article, he could immediately explain why his carbolic soap was saving lives – it was killing the germs that cause disease.

Carbolic acid is no longer used as an antiseptic, as it is highly poisonous. Alcohol and iodine tincture (also known as Choleratoxin) are now preferred as they are safe. Boric acid is used as a dry antiseptic for fungal infections, and triclosan in toothpastes.

Strictly speaking, an antiseptic is a substance applied externally on human and animal bodies only. Anything used to sterilize clothes, floors, walls, surgical instruments, swimming pools etc is known as a disinfectant. Common disinfectants include chlorine, iodoform, hydrogen peroxide, and phenol. Chloroxylenol is used as both, going by the trade name of Dettol.

Harmful greenhouse gas can be used for making pharmaceuticals

A team of chemists at USC has developed a way to transform a hitherto useless ozone-destroying greenhouse gas that is the byproduct of Teflon manufacture and transform it into reagents for producing pharmaceuticals.

The team will publish their discovery in a paper entitled “Taming of Fluoroform (CF3H): Direct Nucleophilic Trifluoromethylation of Si, B, S and C Centers,” in the Dec. 7 issue of Science.

Because of the popularity of Teflon, which is used on everything from cooking pans to armor-piercing bullets, there’s no shortage of its waste byproduct, fluoroform. Major chemical companies such as DuPont, Arkema and others have huge tanks of it, unable to simply release it because of the potential damage to the environment. Fluoroform has an estimated global warming potential 11,700 times higher than carbon dioxide.

But one man’s trash is another man’s treasure, and G.K. Surya Prakash—who has spent decades working with fluorine reagents—saw the tanks of fluoroform as an untapped opportunity.

Prakash, a professor of chemistry at the USC Dornsife College of Letters, Arts and Sciences and director of the USC Loker Hydrocarbon Research Institute, describes fluorine as “the kingpin of drug discovery.” About 20 to 25 percent of drugs on the market today contain at least one fluorine atom.

Fluorine can be found in all different kinds of drugs, everything from 5-Fluorouracil (a widely used cancer treatment discovered by Charles Heidelberger at USC in the ’70s) to Prozac to Celebrex.

“It’s a small atom with a big ego,” he said, referring to the fact that while fluorine is about the same size as a tiny hydrogen atom—so similar that living cells cannot tell the two elements apart—it is also extremely electronegative (that is, it has a strong attraction for electrons) making carbon-fluorine chemical bond quite strong, which improves the bioavailability of drugs made with fluorine.

The discovery was the product of many years of trial-and-error tests, hard work that the postdocs performed under Prakash’s direction. Eventually, the team pinned down the precise conditions needed to coax the harmful fluoroform (CF3H) into useful reagents, including the silicon-based Ruppert-Prakash Reagent for efficient CF3 transfer. Fluoroform with elemental sulfur was also converted to trifluoromethanesulfonic acid, a widely used superacid one-hundred times stronger than sulfuric acid.

“In real estate, everything is ‘location, location, location.’ In chemistry, it is ‘conditions, conditions, conditions,’” Prakash said.

Plastics used in medical devices break down

Scientists have discovered a previously unrecognized way that degradation can occur in silicone-urethane plastics that are often considered for use in medical devices. Their study, published in ACS’ journal Macromolecules, could have implications for device manufacturers considering use of these plastics in the design of some implantable devices, including cardiac defibrillation leads.

Kimberly Chaffin, Marc Hillmyer, Frank Bates and colleagues explain that some implanted biomedical devices, such as pacemakers and defibrillators, have parts made of a plastic consisting of polyurethane and silicone. While these materials have been extensively studied for failure due to interaction with oxygen, no published study has looked at interaction with water as a potential failure mechanism in this class of materials. In a cardiac lead application, these materials may be used as a coating on the electrical wires or “leads” that carry electric current from the battery in the device to the heart. Surgeons implant pacemakers in 600,000 people worldwide and defibrillators in 100,000 people in the United States each year. Since these implants must function reliably for years, the scientists wanted to determine whether the plastic material was suitable for long-term implants.

Segmented polyurethane multiblock polymers containing polydimethylsiloxane(CAS number is 541-02-6) and polyether soft segments form tough and easily processed thermoplastic elastomers. Their laboratory tests, including accelerated aging of the materials under conditions that simulated the inside of the human body, found indications that the material begins to break down within 3-6 years. “By making the conclusions of this novel, scientific research public in a respected peer-reviewed journal, device manufacturers may now consider these important findings in their device designs,” says Chaffin, distinguished scientist and lead author of the manuscript.

The Significance Indigo To India’s History

Well, we know chemistry influences the world. But did you know the curious history of a chemical accident – that’s tied to India’s struggle for independence?

The Blue Gold
Indigo is a blue dye which comes from the indigo (neel) plant grown in India. For
the East India Company (and later the British Raj), it was one of the most profitable commodities that it bought in India and sold in Europe. It was so valuable as a dye that it was called ‘blue gold’.

A lot of Indigo was grown in Champaran district in Bihar. The conditions for the farmers were cruel. They had no land of their own and leased land from zamindars. In return every farmer had to grow indigo compulsorily on 3/20th of the land (for which he was not paid), or pay a penalty of Rs. 100/- (called tawan). But they got nothing in return – the profits went entirely to the zamindars and the British.

A thermometer breaks, prices fall
The British controlled the entire trade in indigo. Other European countries
resented this. The giant German chemical company BASF poured in 18 million marks over several years to find a cheap way to make indigo.

A promising method was to make it from a material called phthallic anhydride (PA). PA is in turn obtained from naphthalene, which is present in large amounts in tar. But the method was not cheap.

In 1896, a technician called Eugene Sapper (sadly, not much is known about him) was trying to make PA by boiling naphthalene with strong H2SO4. While trying to measure the temperature, his hand slipped and the thermometer broke. The mercury in it reacted to form mercuric sulphate, which immediately acted as a catalyst. He got a much larger amount of PA than expected!

BASF quickly realised what this meant. More PA from the reaction meant cheaper PA, which meant cheaper indigo. Cheaper indigo meant that European countries did not need natural Indian indigo anymore. Over time, they stopped buying from the British, and even sold it to textile mills.

The Champaran Satyagraha
Natural indigo started making huge losses to zamindars. But they passed on these
losses to the farmers because they could still collect tawan. This drove the farmers deeper into poverty, as they had to sell their homes and other possessions to pay off the tawan. Many of them became so poor that they abandoned their homeland to become labourers in sugarcane plantations in Fiji, Trinidad and Mauritius.

In 1916-17, Mohandas Gandhi visited Champaran and understood the conditions of the farmers. He immediately went on a satyagraha asking the colonial government to stop the nasty practice. Instead, the British arrested him. Hundreds of thousands of people in India joined his protest, shaking the British government. It finally conceded, abolished tawan and gave more control over land to farmers.

The success of the Champaran Satyagraha showed that the struggle for independence could be achieved through truth and non-violence. Thirty years later, India was free.

Improved performance for solar cells

Photovoltaics is still an expensive technology. Dye-based solar cells may represent a more cost-effective alternative to traditional solar cells. In these cells, a dye is used in place of a semiconductor to trap the light. Tandem cells consisting of both a conventional n-type and an “inverse” p-type dye-sensitized solar cell seem to be especially promising.

In the journal Angewandte Chemie, a team of Australian and German scientists has now reported a significant increase in the degree of efficiency of p-type dye-sensitized solar cells through use of an electrolyte based on a cobalt complex.

Conventional n-type dye-sensitized solar cells use a photoanode, a positive electrode coated with an n-type semiconductor, such as titanium dioxide, and a dye. When light strikes the electrode, the dye molecules become excited and release electrons—negative charges, hence the n in n-type—and “inject” them into the n-type semiconductor. The redox mediator, a component of the electrolyte that can move freely between the electrodes, regenerates the dye by resupplying it with electrons from the counter electrode. In a p-type cell, the process is reversed: a special dye and a p-type semiconductor are located on a photocathode. The light-activated dye “sucks” electrons out of the valence band of a p-type semiconductor such as nickel oxide. This effectively transfers “electron holes”—positive charges, hence the p in p-type—from the dye. The redox mediator takes the electrons from the dye and hands them over to the counter electrode.

A very promising approach for increasing the performance of photovoltaic cells is to combine both an n-type and a p-type dye-sensitized solar cell to make a tandem cell. However, despite some progress, the performance of the p-type cells still significantly lags behind that of their n-type counterparts. An international team of researchers from Monash University and the Commonwealth Scientific and Industrial Research Organization (Australia), as well as the University of Ulm (Germany), have now achieved a considerable improvement in the efficiency of p-type cells by choosing a different redox mediator.

Researchers working with Udo Bach and Leone Spiccia replaced the previous, commonly used iodide and triiodide system with a well-known cobalt complex, tris(ethylenediamine)cobalt(III) , in which the cobalt can switch between the +2 and +3 oxidation states. The advantage of this system is that the redox potential is significantly lower. As a result, the open-circuit voltage, a critical parameter for solar cells, is doubled and there is still a high enough driving force to ensure rapid and efficient regeneration of the spent dye. These devices achieve an energy-conversion efficiency of 1.3 %, while previous systems attained a maximum of only 0.41 %. The p-type dye-sensitized solar cell with the cobalt-based redox mediator even gave promising performance data under diffuse sunlight experienced on cloudy days.

What Does IUPAC Do For Chemisrty?

Imagine you’ve just discovered a great new chemical and you tell the world. Someone else now claims that she discovered it first. Whom would you go to, to decide the facts? You go to IUPAC.

The 1860 Conference
The 19th century was a time when there was a new chemical discovery almost every day. Sometimes, the same chemical would be found in labs in different countries, and get different names. For example, what was called phenol in Europe was called carbolic acid in England; the word alcohol may refer to a class of compounds or just ethyl alcohol. Is the chemical with symbol S spelt sulphur or sulfur? Because of this, it was decided that a committee of eminent chemists would help create some rules for giving chemicals their names.

The committee was headed by August Kekule, and called for a conference in 1860. They also decided to form a permanent association of chemists, where they could discuss all issues, not just names.

Modern Rules
Names of chemicals are not decided like names of babies. They have to be based on the number of atoms in the molecule, their positions and what they do in chemical reactions.

Suppose you made a new chemical whose formula was Cl-C6H4-COOH. You have a chloro bit (Cl), a benzene bit (C6H4) and a carboxylic acid bit (COOH). So you pull out your Blue Book and get the names for the bits. Put them together to make chloro benzoic acid! Easy-peasy!

IUPAC does more than give names
Chemists look forward to the jumbo IUPAC General Assembly, which happens once in two years. That’s when the committees meet and the rules are agreed upon. The next General Assembly will be in 2011, in Puerto Rico. It will be a special meeting, as it marks 100 years of the Paris meeting. IUPAC has joined hands with UNESCO to celebrate 2011 as the “International Year of Chemistry”, with events all over the world.

IUPAC also puts together books that all chemists need as reference material, like lists of melting points, solubility of different things in water, standard methods for doing experiments and a lot more. Many of these books take a lot of hard work over many years.

Most chemists are often happy to tinker in their labs and come up with new stuff, knowing that IUPAC is there in the background, making life easy for them!

More Further Facts About Perfume

Perfume is a magic thing to make women and men become charming. It creates an atmosphere of beauty around its wearer, and can be a delight to those near her. It is also an investment in future happiness. However, few people know the details about perfumes.

They were first used in ancient Greece and Egypt, and for thousands of years they were made from natural materials such as flowers, plant oils, resins and roots, and oils from the scent glands of such animals as the musk deer. The foundations of modern synthetic perfumes originated during the 19th century with advances in organic chemistry. Synthetic scent compounds are less expensive than organic ingredients, and are used instead of, or in combination with, natural oils.

Ambergris is a substance that is found in the digestive tract of sperm whales, and it has a musky, floral scent. Ambergris, also referred to as amber, was historically a popular fragrance ingredient. Ambergris is now reproduced synthetically.

A perfume consists of 78 to 95 percent ethyl alcohol. The staying power of a scent compound in a perfume depends on its rate of evaporation. Modern perfumes contain many synthetic compounds that are altered to give them unique characteristics such as increased odor. Popular synthetic scents used in perfume include benzyl acetate, a synthetically produced jasmine scent, Galaxolide, a synthetic musk-like scent, and ethyl linalool, a lavender scent.

Healthy Problems
There are more than 3,000 base ingredients that manufacturers draw on to make a perfume. Many compounds in perfumes are synthetic such as galaxolide (a synthetic musk) and diethyl phthalate, a plasticizing agent. These chemical compounds are used to make a fragrance’s scent last longer. Phthalates can accumulate in the body’s fatty tissue, and the use of some phthalates has been banned in Europe because of fears of damage to reproductive health.

The history of chemical photography

Today, with a digital camera, we can snap an image, upload it on the net and share it with our friend in a jiffy. But when photography started, it took hours to take a photograph, which would come out very blurred. Let’s take a trip backward in time, and see how photography began.

Photographs today
The physics of photography has never changed, ever since Mo Zi of China discovered it nearly 2400 years ago. He called it the ‘locked treasure box’. Light is let in through a tiny hole in the box (‘camera’ is the Latin word for room), where it falls on the opposite wall. There an image appears, of the thing being photographed. However, it depends on chemistry to actually record the image.

In a digital camera the image is recorded on a ‘camera sensor’ that has thousands of light-detectors which capture the amount and colour of light. Your photo is actually stored as an electronic code, which is decoded by your computer. Hardly chemistry at all.

How mom and dad took photographs
When a photo was taken, light reacted with silver iodide, causing it to break down into silver and iodine. Silver would deposit as dark spots on the film. Darker areas formed where more light fell, and vice versa. Depending on the layer, you’d have a silver spot matching the colour to which the layer was sensitive. This was called a ‘colour negative’ (they just called it a negative). Ask mom or dad; they might still have a few negatives from the old times.

Once photography was done, the ‘negative’ would be given to a ‘studio’ to process. In the studio, the technician would first put it in a ‘developer’ solution. The developer was a chemical called CD-4, which did two things. It made the conversion of silver iodide to silver go faster. It also reacted with the dyes, making them stick to the film along with the silver.

The negative was then converted to a ‘positive’. In this the negative was put in front of a light source, and projected onto photographic paper. (This is not very different from how a slide projector works). The photographic paper had light-sensitive dyes coated on it. When the photo was developed, it was washed and dried and finally ready to be given back to the customer. This was called the C-41 process. In those days, photos would take weeks before you could share them with friends, and photography was an expensive hobby.

How grandma and granddad took photographs
Life was simpler in their times, and also colourless. The nitrocellulose film used was coated with a single layer of silver iodide. When the photo was taken, it would come out in black and white. The negative was the exact opposite, dark in areas of more light and light where there was more light. Ask your grandma to show you negatives of their photos. You’ll see pretty weird images, in which pretty people might look quite ugly, the sun is a black disc and night looks like bright day!

Commen Sense About Cytarabine

Cytarabine is a chemotherapy drug used to treat certain kinds of cancer. Most commonly the drug is used to treat acute myeloid leukaemia. While it is effective against cancers, cytarabine also injures some normal, fast-growing cells across the body. As is common with most chemotherapy drugs, certain mild to severe side effects are associated with it.

Acute myeloid leukemia is a common bone marrow cancer that occurs most often in middle-aged adults. The disease causes defective white blood cells (WBCs) to be produced, and these then proliferate in the bloodstream, crowding out the normal leukocytes and the red blood cells needed to carry oxygen throughout the tissues. Since leukocytes are vital to the immune system, patients may suffer from more infections and general immunodeficiency. The non-Hodgkin lymphomas are a group of different malignancies of lymphatic cells. Drugs that treat these cancers target their cell cycles, the processes by which they reproduce.

Cytarabine is used alone or with other chemotherapy drugs to treat certain types of leukemia (cancer of the white blood cells), including acute myeloid leukemia (AML), acute lymphocytic leukemia (ALL), and chronic myelogenous leukemia (CML). Cytarabine is also used alone or with other chemotherapy drugs to treat meningeal leukemia (cancer in the membrane that covers and protects the spinal cord and brain). It is in a class of medications called antimetabolites. It works by slowing or stopping the growth of cancer cells in your body. This drug is given over a several month period and is placed into the body through injections into veins.

It is possible that those treated with Cytarabine will experience an allergic reaction to the drug. As a bone marrow suppressant, cytarabine can kill some some normal blood cells and prevent more of them from being made, resulting in anemia and immunodeficiency. The medication also can cause a severe decrease in the number of blood cells in your bone marrow. This may cause certain symptoms and may increase the risk that you will develop a serious infection or bleeding.

Garbage bug may help lower the cost of biofuel

One reason that biofuels are expensive to make is that the organisms used to ferment the biomass cannot make effective use of hemicellulose, the next most abundant cell wall component after cellulose. They convert only the glucose in the cellulose, thus using less than half of the available plant material.

“Here at the EBI and other places in the biofuel world, people are trying to engineer microbes that can use both,” said University of Illinois microbiologist Isaac Cann. “Most of the time what they do is they take genes from different locations and try and stitch all of them together to create a pathway that will allow that microbe to use the other sugar.”

Cann and Rod Mackie, also a U of I microbiologist, have been doing research at the Energy Biosciences Institute on an organism that they think could be used to solve this problem.

Specifically, the bacterium contains all of the proteins and enzymes needed to break down xylan, which is the most common hemicellulose, and then to transport the fragments into the cell and metabolize them. All of the genes are located in a single cluster on the microbe’s genome.

“So instead of taking a piece from here and from there and stitching them together, we can just take this part of the gene,” Cann explained. “You can cut this and put it into another microbe.”

On the surface of the cell, there is an enzyme that cuts the xylan into small pieces and a protein that binds to the pieces and brings them inside the cell. Enzymes within the cell metabolize the sugar.

The reason that this microbe, unlike most others used to make biofuels, is able to degrade xylan is that it has evolved an enzyme that allows it to remove the side chains, or decorations, that are part of xylan’s structure. They hinder the degradation process by preventing complete accessibility of the enzymes to the sugar chain.

Having the enzymes next to each other on the genome is convenient for scientists who are working on engineering microbes that can degrade both cellulose and hemicellulose. The cluster could be designed as a cassette and put into a microbe that normally degrades only cellulose.

Moreover, being next to each other allows them to work efficiently. “You have a set of enzymes that have co-evolved,” Cann explained. “If they have co-evolved over millions of years, it means they have been fine-tuned to work together.”