Balls from Fury: Buckminsterfullerene (C60)

  There’s a molecule out there that can hit a stainless steel plate at 15,000 mph and just bounce back. It’s the state molecule of Texas, if that says anything. And you probably already know what it looks like. If you said the molecule is a buckyball, you’re correct. Buckyballs, specifically C60, look almost exactly like a regulation soccer ball, in order to produce extremely stable sp2 bonds throughout all 60 of the

carbons. Buckminsterfullerene, the more technical name for buckyball, was based on the domes of world famous architect Buckminster Fuller. The purported structure of C60 upon its discovery looked remarkably like many of his domes (well, more like B80but that’s another story).

Buckminsterfullerene has a density of 1.65 g/cm3. In its solid form it takes on the appearance of rather dark, needle-shaped crystals. It won’t stay that way for long, for it sublimes at around 800 K. Being that it’s made up of all carbons, it’s a nonpolar substance; it won’t dissolve in water, and it’ll barely dissolve in other nonpolar substances like benzene. When stimulated with life, it prefers to act as an electron acceptor, in the same manner as an electron-deprived alkene. Unless it’s in solution, it doesn’t prefer to be reduced, with each individual reduction from C60 to C606- being negative and approaching the penultimate -2.549 V at the final reduction at 213 K. It does prefer being oxidized, however, at very low temperatures, though past C60+ the products tend to be rather unstable. And here’s a kicker–buckyballs are the largest known molecule to exhibit wave-particle duality (at least in a diffraction grating). It’s a wonder we’ve even discovered a molecule with these properties; in fact, mostly everything about this molecule is still a wonder.

 One of the Best Accidents?

 C60 became nothing short of a chemist’s dream come true upon its discovery in 1985. Yet, it was discovered purely by accident by H.W. Kroto, J. R. Heath, S. C. O’Brien, R. F. Curl & R. E. Smalley at RICE University in Houston, Texas. The understanding of how long chains of carbon were formed in interstellar space was sought. Lasers shot at a rotating disk of graphite in concentrated helium, and… well, the researchers ended up being inevitably shocked. Sure, they found molecules containing 40 or more carbons, but most prominent was the presence of 60 carbons (followed by 70). Conventional structures did not seem to work in having a molecule of 60 carbons be stable, so they sought alternatives. One structure they noted is as follows: “the C60 molecule which results when a carbon atom is placed at each vertex of this structure has all valences satisfied by two single bonds and one double bond, has many resonance structures, and appears to be aromatic.” Even by this alone was the structure hinted at. They hypothesized that “fragments are torn from the surface as pieces of the planar graphite fused six-membered ring structure. … When these hot ring clusters are left in contact with high-density helium, the clusters equilibrate by two- and three-body collisions towards the most stable species, which appears to be a unique cluster containing 60 atoms.” They even specified the diameter of the molecule, 7 angstroms, which was enough to stick an atom inside. The rest of the chemistry world found this discovery to be nothing short of awesome, and Kroto, Curl, and Smalley were awarded the 1996 Nobel Prize in Chemistry for this.

The only issue in the discovery was that the initial method of production failed to produce substantial quantities of buckyballs. 5 years later, a technique using the evaporation of graphite electrodes in a light atmosphere of helium emerged, allowing for the mass production of buckyballs. Or, as discovered later on, one could just sublime the buckyballs out of graphite.

Possibly the Only Ball Safe for Human Consumption

    In these previous 29 years of existence buckyballs have found potential uses in this world. For instance, doping a buckyball with potassium results in a superconductor that is functional at temperatures of 18 K, which a high temperature for a superconductor. Moreover, there’s evidence to show that buckyballs can bind to the insides of the protein HIV protease, effectively inhibiting their function and not allowing the HIV virus to replicate. And they may be even useful antioxidants. Buckyballs have a tendency to act as an electron reservoir; they can give free radicals (molecules specifically desiring an electron to become stable) the extra needed electron in order to stop them from taking electrons from other molecules inside the body. Plus, C60 is known to not be toxic to human cells, and it has the ability to go inside of cells rather easily. In fact, there’s olive oil with buckyballs dissolved in it at a concentration of 45 mg/50 mL on the market.

You Might Want to Duck

 

Even when leaving the confines of Earth, buckyballs were from its discovery speculated to exist in interstellar space, specifically because it has the ability to form in some of the mostadverse conditions known to exist. One theory about its formation is that UV irradiation takes PAHs (polycyclic aromatic hydrocarbons) and converts them to graphene and then into buckyballs. This is seemingly more efficient than an alternate explanation, one in which carbon atoms clump together in the hot, dense center region of stars.

The first place that buckyballs were found in (along with hydrogen) were planetary nebulae. Three nebulae with dying stars like ours contained these buckyballs; what makes this remarkable is that these stars were in our own galaxy. (Even more so, there was a nearby star containing buckyballs in a mass of nearly 15 times larger than that of our own moon). Nebulae are emitted by dying stars; in the middle of all the layers of gas being shed there is a white dwarf holding it all together. There is a stage where the white dwarf spits out a lot of carbon. Even more astounding was the hydrogen it was found with: researchers had previously assumed that the presence of hydrogen would cause it to form the chains and rings originally sought after. And that was just in the gaseous form: in 2012 it was found in solid form. What that means is not yet clear, but it can imply that it might have been a building block of life.

You’re probably sitting there shaking your head. So what if a molecule’s been found in space? It probably isn’t of much importance, is it? All these claims are surely false. Wrong. Buckyballs have been found in meteorites. Meteors, being the huge hunks of rock they are, have the ability to house materials not seen and never before seen on a planet. When they become meteorites and slam into Earth, not only does the resulting collision cause adverse climate changes (which no organism really likes, as evidenced by mass extinctions usually brought along with them) but it can also spread those materials all over Earth.

As stated at the beginning, a buckyball can hit a stainless steel plate at 15,000 mph and just bounce back, and it can also house atoms or even molecules inside. For instance, there was anasteroid impact marking the end of the Permian period, which took out nearly all life on Earth. The meteorite has been found to contain buckyballs housing helium-3 and helium-4, with helium-3 now being present in the atmosphere.

“Buckyballs are carbon molecules in the shape of a cage and they are very tough and hard to destroy,” said Kris Sellgren, a professor of astronomy at The Ohio State University in Columbus, OH.  She noted that although life forms, let alone a single molecule of DNA, absolutely dwarf a buckyball, “single atoms or small molecules can become trapped and can survive inside the cage while the buckyball safely travels through the harsh conditions of space.”

“Buckyballs with extraterrestrial gases trapped inside them, for example, have previously been found in meteorites that have slammed into Earth. Spotting buckyballs in interstellar space also reveals that relatively big molecules can persist and maybe even form in the diffuse, unforgiving voids between the stars.” These are something your regular soccer balls can’t handle.

Will It Go ‘Round in Circles: PAHs

What are PAHs?

PAHs, short for Polycyclic Aromatic Hydrocarbons, are groups of naturally occurring or man-made chemicals that result from the incomplete burning of many fuels such as coal, oil and even gas. When drawn, they look like multiple rings of benzene bonded together to form chains or sheets or… other odd shapes. You’re probably thinking, “How are rings going to hurt me?” Yet they do. They have been linked to cancer and can even hinder reproductive health. Clearly, in our current age and society the abundance of PAHs is potentially much higher than any previous generation. It is also necessary to notice that substances which produce the most PAHs are the compounds with the most moles of Carbon. Other than messing around, PAHs have two primary uses: research and dyes. They are also used to make plastics and pesticides. 

That’s Great, but what do we actually see?

PAHs in their base forms, because they are made of only carbon and hydrogen, are organic molecules and are thus nonpolar. Thus, they barely dissolve in water if at all, but they love to dissolve in fats, oils, and other organic solvents. PAHs are all solids, but their form depends on which method is used to crystallize them–some end up forming needles or plates. Their colors vary: for instance, anthracene is colorless in its purest state, benzo(a)pyrene is pale yellow, and pyrene can be either depending on the method it is crystallized.

 

I Thought Rings Were for Marriage

You’re probably thinking, “Oh, it’s an organic molecule, right? It can’t possibly be bad for me…” Apparently, the only type of rings the body tolerates come in the form of engagement and marriage. The body really doesn’t want PAHs inside. For starters, 200 of them are found in cigarette smoke, and many of these have the ability to hinder reproduction. Then they have the ability to indirectly cause cancer.

Benzo[a]pyrene is one of the worst PAHs there are; its effects have been well documented. Chimney sweeps often found themselves getting scrotal cancer due to this compound–in the mid 19th century. In today’s world, benzo[a]pyrene has been found in cigarette smoke, being one of the molecules that could potentially cause lung cancer, among others, by binding to DNA. In doing so, they may end up interfering with DNA replication. The mechanisms by which the DNA is metabolized are far too complex to be understood here (at least at the high school level for someone who hasn’t done any research), but know this: the body metabolizes it to form its toxic forms. Not only that, but it hampers your immune system. Overall, the body metabolizes benzo[a]pyrene and many other PAHS through microsomal enzymes, forming compounds that bind to DNA and introduce mutations.

And You Might Be Wearing Them Now

Most PAHS lack practical everyday uses, barring that some of them are toxic. Most of them that are used are used for research purposes only. Yet, as previously mentioned, some could be on you right now in your clothing. They were used in the process of making the color. The PAHs that have dyeing abilities include but are not limited to anthracene, carbazole, and pyrene. Anthracene is used to make red dyes, carbazole for violet, and pyrene for fluorescence. This technology has been used for quite a while; the patent for anthracene and its process was filed in 1925. Also, while its status as a PAH is debatable, naphthalene has been found in mothballs, a critical component of clothing storage, though it has been phased out because it has a tendency to catch on fire. But in the more practical sense, PAHs show up in many things derived from coal tars, including asphalt (the stuff cars drive on) and even cosmetics (things you put on your face).

 

And in a way that could actually benefit humanity, some PAHs are implemented into dye-sensitized solar cells. Dyes are used to boost output in otherwise unfavorable conditions while also diminishing costs by eliminating some of the expensive materials used in it. These dyes are often coated on the titanium dioxide found in the solar panel. The dyes can be based off of PAHs, for they give them superb photoconducting skills. For instance, carbazole is made electron-rich due to its nitrogen atom, making it useful for the  electron transfer necessary to induce current. And a dye known as TC501, bridged by anthracene, improved the open-circuit photovoltages and short-circuit photocurrent densities of a dye-sensitized solar cell, so much so that the solar conversion efficiency jumped to 7.03%, which is a relatively remarkable number. Many of the mechanisms by which PAHs assist in photoelectric conversions are specific to that PAH, and some of them are not yet fully understood. And speaking of extraterrestrial energy…

There’s Plenty of Space for This Poison Elsewhere

Naturally, we are able to observe things specifically on the planet Earth, otherwise we need either telescopes or overactive imaginations (we recommend some of both). Using this, science can now tell us that certain molecules also occur outside in the cold, not-empty void of interstellar space. The spectra of PAHs have been found in conjunction with large molecular and dust clouds; it is speculated that they form by photoionisation, which is also what causes hydrogen clouds to form in these places. Photoionisation, as the name may suggest, involves light providing the energy to ionise molecules and cause them to form into compounds. Sounds like a great way to cook

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For those who have an inexplicable fear of deep space, there’s something for you as well. PAHs have also been found in the atmosphere of Titan. Titan, as you should probably be required to know, is Saturn’s largest moon. It’s unique because it is the only moon to maintain a substantive atmosphere. To the average flying robot, it is an orange ball. Titan is a lot closer than all interstellar space, so we can accurately detect what is in the ball of Orange. It turns out that, besides a load of nitrogen (boring), there are PAHs as well. Those that the European Space Agency found are a bit more complex than the ones our beleaguered lungs are most familiar with, but they are still the same sort of molecules. It may be worth adding here that Titan also seems to have surface lakes of hydrocarbons, which may be of similar origin. Seti, or the Search for ExtraTerrestrial Intelligence, has found indications that these molecules, besides being distributed in gas clouds, are also found in interstellar dust and locked up in water ice. These are the basic ingredients in planet formation and by extension that of more complex organic forms.

Good Poison?

You learned earlier that PAHs often result from the burning of organic or fossil-derived materials. The existence of such complex  molecules in both interstellar clouds and the atmosphere of a moon suggest that maybe the molecules related to life are not so rare as we might’ve thought, and it certainly opens some new eyes and avenues for which to explore. Scientists have been forever intrigued by the presumably unique condition of life on the planet Earth. With the discovery of new worlds beyond our solar system, and the recent insights into the conditions on some places a bit closer, perhaps we will discover that, just maybe, we are not alone.

Don’t Drink in Space

Water is great. It nourishes, relieves thirst, cools one off after a run, and is used in countless unhealthy beverages. What’s notable about those particular uses is that they are specific to Earth, for this is the only place in the universe where water is known to occur as a liquid on the surface. Now, that doesn’t preclude the other types of water, namely solid and gaseous, from being found anywhere else. It turns out that they are, and water as a molecule is extremely abundant in space and even, as you’ll find out if you don’t fall asleep, in the farthest reaches of space.

 I Always Thought Marvin Looked Like a Diver

By now, you all probably know that water ice is found on Mars. Just observing the planet, if you are lucky enough to own a telescope, reveals the white north polar ice cap, which is composed of frozen water with a lot more frozen carbon dioxide. It is thought that water once flowed on the ruddy surface of the planet but now it clearly does not. Bummer.

Water ice, however, does occur in other places, such as Europa, Ganymede, Enceladus, Triton. Pluto, Ceres, comets, and many small bodies in the outer solar system. Fortunately, water ice has a number of interesting properties that enable scientists to detect its presence and make inferences about the makeup and formation of celestial bodies.

Sinking Moons

Recent news from the Saturn system indicates that Enceladus, one of the ringed planet’s larger moons, may possess a liquid water ocean below its surface. It was the properties of water that enabled scientists to even think of presenting their findings. Enceladus’s surface is mostly water ice, which gives it a high albedo. Enceladus’ core, like almost everything else in the Solar System, is made of a dense, hard material known as rock. The different things on Enceladus obviously have different densities, with rock being very dense and the ice not being very dense at all. Note that we have not mentioned what is between the ice and core. Things settle based on their densities, as the age-old experiment with oil and water shows. Therefore, there must be some mass of substance denser than ice but less dense than water, and although Enceladus’ interior is heated it is not hot enough to melt rock, so it is not magma. The only other thing that made sense was liquid water, the necessity for known life, and that is what was sent to the presses a couple of weeks ago.

Elmer’s Ice

But now this is just talking about water in space- why not some chemistry? Research done in the past few decades and years indicates that water is found abundantly in the interstellar medium, including in dust clouds. Water has theall-important quality of being polar, and so it can use that property to hold things together. It turns out that water, in its ice form probably, acts as a glue to hold dust grains together. Dust grains are probably one of the most common things in interstellar space and in the appropriately named dust clouds, which also contain interesting things such as organic compounds and sometimes metals. A lot of dust grains held together can form bodies, which under the force of gravity become round and turn into things like planets and their moons. So, we see the very real power of water as being partly responsible for planetary formation (with gravity).

Water Factories in Space

Although one does not realize this frequently, the water found on Earth was not made here. It came from space. This of course leads to the question of how was such an abundant amount of water made in space, when we can barely detect water in space? Well first off, this process takes a very long time to complete, therefore is not noticeable at any moment. It first started with the Big Bang, after which Hydrogen (one of the most abundant elements in the Universe) was created. The Oxygen was produced at the centers of massive stars and dispersed into space by stellar winds or supernova explosions. The Hydrogen eventually reacted with the Oxygen to form water. However, this reaction cannot take place anywhere. The ideal conditions for said reaction are found in places such as star-forming regions, for example, the Orion Nebula. Some of these newly formed water molecules start to travel out into the cold of interstellar space, where they form ice grains. As stated earlier, they will end up in comets or in planets like our own.

It is interesting to note that, the Orion Nebula is also the site of creation of stars. Although, the distance between our own planet and Orion makes it hard to study it, spectroscopy let scientists deduce many properties of the objects emitting the light, even if they can’t see them clearly. This is how the vapors and other elements in the nebula were discovered.

Cloudy With a Chance of Quasars

 The oxygen that is in water is also very important; as it is a very reactive element. It has the ability to form numerous molecules even considering the makeup of molecular clouds, which are mostly hydrogen but with quite a bit of oxygen and some carbon, so we find that the most common simple compounds are water and carbon monoxide/carbon dioxide. It’s not as if water is even a recent development in the very long history of our universe. Scientists have detected enormous clouds of water vapor around quasars, also known as those tiny little galaxy-things that pre-date galaxies and that were present around 12 billion years ago, or less than 2 billion years after the Big Bang. This means water was already coalescing in huge amounts in less time than it took multicellular life to evolve. There also appears to be a black hole involved, to make things more interesting. What’s more, the cloud is relatively hot (as are quasars in general) but not very dense. This provides more evidence for the role of water in the basic formation of familiar matter objects in the universe, meaning it is extremely pervasive. In the search for life elsewhere, this is helpful information.

Chemistry of the Brain: Neurotransmitters

           Our brain performs numerous functions throughout the day which lends itself the question, ‘how are these functions carried out?’ What processes or chemicals facilitate these functions. The biochemicals responsible for this are called neurotransmitters. The process for information to be transferred begins at the neurons in our brain. Chemicals, called neurotransmitters, are passed between neurons through gaps called synapses. Essentially, the neurotransmitter is passed from one neuron to the next where it may be accepted at the neuron receptor. At the receptor the action potential of the neurotransmitter is either likely to happen or unlikely. Some of these neurotransmitters are epinephrine, serotonin, and histamine.

Epinephrine

Epinephrine is a neurotransmitter that is very prevalent in our lives. More commonly known as adrenaline, epinephrine is responsible for the ‘Fight or Flight’ response in our brain. With a C9H13NO3 molecular formula and a 183.20 molar mass, epinephrine is actually secreted by the medulla in the adrenal gland in the kidney. For this reason, epinephrine is considered both as a hormone and a neurotransmitter by many chemists. Although its secretion site is different from the other neurotransmitters, epinephrine’s creation in the medulla makes sense because the medulla is responsible for maintaining homeostasis in the blood between blood, salt and water. It seems logical for a chemical revolving around ‘Flight or Fight’ because during times of high pressure and stress, epinephrine is secreted which then stimulates the heart thereby changing the blood pressure. The increased

blood pressure increases the rate of the heartbeat, thereby increasing the flow of O2 into the bloodstream and to the tissues. The respiratory passages becomes dilated, thereby increasing the input of O2. The increased heartbeat and blood pressure increases reaction time in the animal thereby keeping it more alert during the time of stress. In addition, epinephrine also gets sent to the muscles and lungs for a quick burst of energy.

 Serotonin

           Serotonin is a neurotransmitter, but you’d be surprised where it is: ninety percent of it is not anywhere in your nervous system. Eighty percent of it is in your stomach, regulating intestinal movements. Another ten percent is in your blood platelets, where it regulates hemostasis and clots the blood. The last ten percent is in your central nervous system. Serotonin has a molecular formula of C10H12N2O and a molecular weight of 176.25 g/mol. But what is this relatively simple molecule (in comparison to monsters such as hemoglobin) doing in your intestines? Serotonin is proven to have control over smooth muscle, which controls involuntary

movement of muscles;  it just so happens that your intestine is made up of smooth muscle. But serotonin is also a regulator, which is why it is located in the nervous system. The two brain structures where it resides are the hypothalamus, which deals with regulation of homeostasis in general, and the basal ganglia, dealing with movement and thinking.

            If you’re suffering from sleep deprivation, a good portion of the problems you experience are blamed on serotonin. Studies have shown that a limited amount of serotonin has led to depression, insomnia and a strong desire to consume food. Ever wake up in the middle of the night and get a midnight snack? Serotonin regulates insulin and IGF, critical in the maintenance of blood sugar levels. In addition to controlling food, serotonin (along with melatonin) is involved in regulating our sleep and wake cycle (also called a circadian rhythm): high levels of serotonin are associated with wakefulness and lower levels with sleep. Thus, when you’re sleepy, you might also get hungry. Also, since serotonin controls and regulates our thoughts so that they flow in a orderly manner, as one sleeps their serotonin levels decrease and our thoughts become able to run wild to the point where our brain is able to create its own images, also known as dreams, during REM sleep. In a medicinal sense, anti-depressants often work as selective serotonin reuptake inhibitors (SSRIs), where they block a neuron from taking back the serotonin for later use, allowing the desired emotion to continue being perceived (in this case, usually pleasant experiences).

Histamine

         Compared to other neurotransmitters, histamine is a relatively small compound; its molecular weight: 111.15 g/mol. Histamine is an amine, being based off of a nitrogenous compound. Most everyday discussion and recognition of histamine revolves around its function in the immunological response to allergens. This is what creates the classic systems of an allergic response; the runny nose, watery eyes, and endless sneezing that characterize this event. Many of you who happen upon this may sympathize and roll your eyes when the calendar hits April.

           Besides its well known role in the allergic response cycle, it is responsible for the physiological regulation of the gut and is important as a neurotransmitter. It causes capillaries to increase in their permeability to white blood cells in order to counteract invaders, and is found in essentially all animal cells. Histamine is formed by the removal of a carboxyl group from a molecule of the amino acid histidine. This reaction occurs in things called mast cells, although it has also been found produced in the white blood cells in lungs that produce pus. Besides that, histamine can be found in the brain and acts a neurotransmitter.

           It was only recently, within the past two or three decades, that histamine’s role as an important neurotransmitter was discovered. In this form and function, it originates from the posterior hypothalamus and is relevant in most of the brain beyond that. As a neurotransmitter, it is most closely linked with arousal, pituitary secretions, and waking, as well as suppression of eating. It has been found that low levels of this molecule correspond with convulsions and seizures, and also sufferers of Alzheimer’s disease. Conversely, high levels of histamine are recorded in patients with Parkinson’s disease and those with schizophrenia. Histamine also seems to be involved in recovery from brain injuries involving the neurons. It is also known to be vital to maintaining the sleep-wake cycle. particularly in maintaining wakefulness. This information is particularly valuable to constantly sleepy students.

Conclusion

          And so, neurotransmitters are what get information from your brain out towards wherever it needs to go. Here, three of those neurotransmitters are covered. Epinephrine runs rampant when your family decides to pull a practical prank on you. Serotonin is heavily dependent on sleep; it helps you maintain some of your sanity. Histamine makes sure you don’t die when you eat that lobster. As time goes on, each one of these will take you on an adventure, leading to the end goal of making you aware of what’s going on in your body (not anatomically, chemically) and as to why you should probably get some sleep. So until next time, try and get some sleep, your body (and its neurotransmitters) will thank you for it.