How It’s Made: the Drug Discovery Edition

Medicine, drugs, remedies–whatever you call them, they are a necessary part of 21st century society, and each and every one of them has been discovered or synthesized through a series of reaction. Previously, we have talked about specific drugs, specific structures, and what they did individually, and now, we’re going to tell you why it all works.

Many of the drugs that you take on a daily basis are not naturally occurring, and so they have to be synthesized in a lab through a series of reactions.Many of these reactions include the creation of chemical structures through the combination of molecules at certain places. But I can hear you asking, “Why does it bond together?” Here’s why…

Organic Chemistry and Thermodynamics and Kinetics

This image shows the structures of diamond and graphite.In chemistry, molecules bond with each other if the conditions are thermodynamically favorable, or in other words, if the change in Gibb’s free energy is negative and the reaction is therefore spontaneous. When talking about synthesis for reaction that are spontaneous, it is also extremely important in pharmacology to consider the kinetics of the reaction. There may be a way to create a life-saving drug through one, spontaneous reaction, however if the reaction is kinetically extremely slow, there will never be enough to create a viable amount of the drug. Thus, in drug synthesis, it is important to consider variables that will increase the rate of reaction such as temperature, pressure, and using catalysts. To help visualize this, think of diamonds: the reaction of the crystal turning into graphite is spontaneous, because graphite is a more stable state, but it happens so slowly that you never notice it happening to your own jewelry. So, when creating a drug, developing a reaction is not all that there is to think about.

However, that step is also very important, especially when thinking about how much energy is needed to create the compound, whether or not it would form properly, and if the reverse reaction would be spontaneous if the forward reaction is not. In addition, when considering the reaction itself, it is necessary to consider the chemical structure of the compounds, and how they would bond together. For this, it is necessary to consider their organic chemistry of the compounds, and how they would bond to create the lowest possible energy state for the highest stability. Thus can be done by considering resonance structure, orbitals, bonds, and electron configurations. This is significant because the molecules will form the most stable compound with the lowest potential energy, which in some cases may not be the intended structure.

This shows the reaction for the synthesis of the Quinoline Ring, indicating the structure with the lowest potential energy and thus the most stability.

Intermolecular Forces and Kinetics

When talking about drugs, it is imperative to consider the human body, or whatever body the drug is going into, and the molecules that are in that body. The first main thing to consider is the intermolecular forces between the molecules in the drug and the the molecules in the body. As there will always be London Dispersion forces, and those are dependent on size, it is not as significant as Hydrogen bonding and Dipole-Dipole forces. These forces may impact how the  drugs spread throughout the body, especially with certain enzymes and proteins. Kinetics within the body is also extremely important, because aspects such as the rate of reaction with a certain molecule or organism is important to how concentrated the drug will be, the dosage, and how fast it This is a graph for the half life of a compound, showing the relative time and amount of substance.is intended to work. Also, with kinetics, the half-life of drugs is very important to the parameters of the drug, because depending on the drug, it could be able to stay in the body for weeks or longer because of a very long half life, or have been processed by the body within a matter of hours. One example where this is important is with antiretroviral medications given to patients with HIV. These medications must be taken very often because they have very short half lives and are digested by the body at a very high rate, so in response researchers are trying to develop a drug with a much longer half life so that the drug can be taken much less often and will become a sustainable solution.

Electrochemistry

Electrochemistry is very important in the development of drugs, both for synthesis and for gathering information on different parameters and properties. Some specific examples where electrochemistry is used in research is the investigation of reactive oxygen species, the biooxidative and bioreductive activation of pro-drugs, and DNA alkylation. As for the synthesis, electrochemistry is a widely known and widely used method to create certain physiologically active compounds.

The StruggleThese statistics show the increasing costs of creating new drugs.

The struggle in the synthesis of new drugs is forming an initial reaction that would actually occur. This takes place even before the laboratory, by chemists who research different molecules and how they can be broken and form new bonds with other molecules. In many cases, certain molecules with key structures such
as those mentioned before (beta-lactam ring and quinoline ring) must first have certain bonds broken in order to bond with another molecule at another place. The second task is to find a reaction such that the formation or breaking of bonds at certain places is thermodynamically viable so that the reaction will occur. The next part of this is done in a lab, to test the reaction, to measure its kinetic properties, and to see if the creating of the therapeutic molecule is capable of commercial viability. From there, there are countless reactions that were not planned for which may cause fatal reactions in animal models which make the drug unsuitable for human consumption.

According to recent statistics, only 1 out of 5,000 drugs which are initially created in a preclinical setting are approved by the Food and Drug Administration to come onto the market, making the cost of creating new drugs astronomically high. Not only does this hinder the drug companies, but also the people who buy these expensive medicines. That, is the pharmacological struggle.
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The Future of Medicine: Drug Designing

Using C-F Bonds to Slow Drug Metabolism and Increase Potency

 There is a lot of chemistry that can be discussed about established medicine currently on the market. However, one of the most interesting topics to look into is how new drugs are being developed. With the advanced technology we have today and the vast knowledge of both chemistry and biology that we possess, there is a lot that is done to manipulate chemicals to get the best drugs we can for the purposes we need them for. This is the exciting field of drug synthesis.

Illustration of the various components of a good medicine: the best possible activity, solubility, bioavailability, half-life, and metabolic profile

Of course, there is so much that can be delved into just for this one topic. There are so many factors that make a drug a “medicine.”  The characteristics of a particular molecule are important, and even necessary, to how it functions. Now, what the pharmaceutical industry is trying to figure out how to make these drugs in the most efficient way possible, create more of them with new techniques, and to find those which are most effective in the human body.

Redox Chemistry and Hydrogen Bonding

One of the most studied and crucial characteristics of a drug to know about is how it is metabolized in the body. Most basically, drug metabolismdescribes how a drug is processed and excreted from the body. The metabolism of a certain drug effects how long it will stay in the body, which in turn affects how long effective concentrations of the drug will be able to perform their functions. Of course, therefore, drug metabolism is of interest to many people, particularly to pharmaceutical companies creating new medicines. Luckily, drug metabolism  is largely affected by the chemical interactions of the the drug molecules, which is something that we can control by manipulating chemical structure. Two things in particular, the oxidation of the drugs as well as hydrogen bonding are often taken into consideration.

Here is a quick overview of redox reactions to go over:

Here is a quick overview of hydrogen bonding.

The Carbon-Fluorine Bond

Let us regress for a second, and establish a basis for what we shall talk about. Naturally there are no carbon-fluorine bonds in the human body. Why? They simply do not occur in nature and hence do not show up in the human body. (Usually in nature there are carbon-hydrogen bonds instead.) Yet, strangely enough, looking at the chemical structures of many drugs, many of them do contain carbon-fluorine bonds. This helps the body more effectively process the drugs, since the body does not know how to digest these molecules and they remain in the body longer. This is because of the particular nature of the bonds, namely that it is polar. The fluorine atom is more electronegative than carbon atoms, and therefore pulls electrons towards itself. The fluorine side of the bond is therefore pseudo-negative whereas the carbon side is pseudo-positive. In a drug molecule, polarity hence also pulls the electrons aways from the rest of the molecule. Recall that redox reactions involve the transfer of electrons. An electron poor molecule therefore will not oxidize easily.

Some examples of the incorporation of C-F bonds can be seen below. Cipro is an antibiotic drug, Paxil is an antidepressant drug, and Sitagliptin is an anti-diabetic drug.

 blog 5.JPG

Benefits of Being Harder to Oxidize – Solubility

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The above picture shows a Cyp enzyme bound to the  anticoagulant drug warfarin.

Drugs are metabolized through a redox reactions with two enzymes in the liver, P450 and Cyp. An enzyme is a natural protein that catalyzes chemical reactions in the body. To briefly go over the kinetics, this means means that it is present as a reactant in the first elementary step of a chemical reaction, but also present as a product in the last elementary step. How an enzyme works is heavily tied to kinetics. The two enzymes mentioned work by oxidizing small molecules, which of course includes all drugs. This oxidation make the molecules more polar as the electron distribution in the molecule changes. In every redox reaction there is an oxidizing agent that gains electrons and a reducing agent that loses electrons. In the case of the chemical reactions taking place in the liver, the liver enzymes take electrons away from all the molecules that pass through the system. Often, these extra electrons are transferred and used in many other reactions throughout the body.

 The redox reaction makes the drug molecules more water-soluble which leads to the drug’s secretion from the body. They are more soluble because they are then polar. Recall that water is also a polar molecule. Two polar molecules are often very soluble in one another due to their attraction to each other. Because of this timeless saying, “like dissolves like” the drug is able to dissolve much more easily in the body and spread through the body. Again, the goal going towards the future is to create drugs whose dissolution is more thermodynamically favorable due to a more negative deltaH3, and thus will occur at a faster rate and with more consistent results. Additionally, because it makes the dissolving of the drug spontaneous, with a negative change in Gibb’s free energy. (Overall the change is enthalpy would be negative and change in entropy would be positive, resulting in negative change in free energy.)

A drug that is easily oxidized will be cleared from the body more quickly than one that is difficult to oxidize. Recall that C-F bonds make a molecule electron-poor. Since the drug molecules are the reducing agent in the redox reaction (they are oxidized and hence give electrons,) they are therefore not as reactive with liver enzymes with a C-F bond as they would be if they had a C-H bond instead. Overall, thus, C-F bonds make drug molecules more metabolically stable.

blog 5b.JPGFluorine as a Hydrogen Bond Acceptor

There are more reasons that medicinal chemists replace C-H bonds in drug molecules with C-F bonds. This is because the fluorine atoms, which, as mentioned before, are very electronegative, can be hydrogen-bond acceptors. In other words, hydrogen atoms can be attracted to them. To understand why this is important, it is important to understand how drugs work. Many drugs work by binding to and inhibiting the activity of a target enzyme. How tightly a drug binds to a specific binding pocket of an enzyme determines how potent, specific, and effective a drug is. The more tightly it can bind, the better drug it is. Fluorine increased the potential hydrogen bonding interactions interactions between the drug and its target. In other words, it increases the intermolecular forces

blog 5c.JPG

It has been proven that C-F bonds increase the potency of a drug. One specific example is the drug Januvia, shown below. This is a drug that is used to treat Type II Diabetes. It is composed of six C-F bonds, three of which are in an aromatic ring. While the drug was being developed, the researchers found that even just one fluorine in the aromatic ring increased the potency of the drug three-fold. Three fluorines increased potency 25-fold.

The Future of Drugs (We Hope!)

 The goal for the future is to be able to create drugs more easily and effectively. That would mean being able to make reactions go forward, and find ways to incorporate certain bonds in the structure that would metabolize better in vivo. In addition, creating new reactions, both with the help of redox reactions and with many different synthesis applications such as electrochemistry and the organic chemistry of electron movement is very important for the creating of new drugs. Finding ways to do this that work effectively and efficiently, or in other words are thermodynamically favorable and thus spontaneous, is also a necessary step of the future. Being able to test drugs in a non-animal environment, yet still being able to predict its effects on the body is also a substantial step that needs to be taken, so fewer ineffective drugs will have to go through clinical trials unnecessarily. Overall, the chemists who work in the pharmaceutical industry have a far way to go, and a bright future to go into.

 

They’re Rare from Earth and Metals

The name “Rare Earth Metals” has a special ring to it, branding the set of 17 elements on the periodic table as exclusive and elusive.  However, as we will soon see, this is misleading, and does not show the whole picture.  Much like helium, the rare earth metals are actually quite plentiful in the Earth’s crust.  For instance, cerium is the 25th most abundant element in the earth’s crust. But what exactly are the rare earth elements (REE)? REE are the elements in the lanthanides series as well as Yttrium and Scandium that share unique magnetic, phosphorescent and catalytic properties that make them so essential to our modern technologies. However, currently the major supplier of rare earth metals to the rest of the world is China and they have been restricting their trade.  Since rare earth metals are used in a myriad of applications ranging from hybrid cars to portable electronics, there is a desperate demand for them that is not being filled.

Rare Earth Metals are produced through several different processes usually involving high temperatures and a series of reactions. In the case of Lanthanum which will be the focus of this post, a derivation of what is called the Ames process is used to purify and create the REE. Lanthanum is generally found in its most stable state:, La2O3 and can be readily found in the earth’s crust at around 32 parts per million (ppm). The shortage, as mentioned before, arises because most of the deposits are not economically viable for extraction. This rare metal oxide then has to be reduced to a pure solid so that it can be used for its various purposes. There are even variations of the Ames process for Lanthanum, but an example will be provided and explained as well as a video with a slightly different reaction.

One reaction is the one below:

La2O3 + 6HF → 2 LaF3 + 3H2O

LaCl3 + 3Li → La + 3LiCl

In the first step of this reaction Lanthanum is fluoridated to become LaF3. However in the second reaction Lanthanum is reduced from an oxidation state of +3 to 0, while Lithium is oxidized from 0 to +1. This reaction does a disservice in understanding just how complicated the process is, which takes many steps, and manipulations of temperature. A very similar Ames process and the steps necessary are further explained in the second half of below video.

 

One important application of rare earth metals is in hybrid cars.  Lanthanum is used to make nickel-metal hydride batteries which are used in most hybrid vehicles.  A battery for a Toyota Prius required 10 to 15 kg of Lanthanum; a significant amount of Lanthanum is clearly needed for hybrid cars to expand in use.  The electrochemistry of nickel-metal hydride batteries is as follows.  The battery contains a positive electrode of nickel oxyhydroxide (NiOOH) and a negative electrode of a hydrogen-absorbing alloy.  The discharge reaction on the negative electrode is as follows:

OH− + MH is in equilibrium with H2O + M + e−

As you can see the M, which stands for an intermetallic compound that will be discussed shortly, is being oxidized into MH.  The reaction on the positive electrode is as follows:

NiO(OH) + H2O + e−is in equilibrium with Ni(OH)2 + OH−

In this half-reaction, the Ni is reduced from an oxidation state of +3 to one of +2.  The overall discharge reaction is as follows:

Ni(OH)2 + M is in equilibrium with NiO(OH) + MH

During the overall discharge, the hydrogen ion moves from the negative electrode to the positive electrode which is the principle behind the reaction.  The M in the negative electrode reaction is usually a compound written as AB5 in which A is a mixture of rare earth metals, including lanthanum and B is a mixture of nickel and cobalt, among other metals.  This compound of rare earth metals is of vital importance in forming the metal hydride compound necessary for the reaction to take place.

Now that we exploited the useful properties of rare earth metals, there’s no turning back; rare earth metals are too widely used to be abandoned.  Although they are non-renewable resources, they are relatively abundant in our earth.  Another country needs to step up to take the near monopoly away from China.  This is an unnecessary shortage, and certainty a solvable one.

The Principle Behind OLEDS

Throughout our exciting journey together, we have explored the wonderfully innovative and unpredictable OLED industry in depth all across the spectrum.  We first focused on the bare bones of the basic layers of an organic light emitting diode.  Subsequently, took a figurative trip to the factories, where we learned about the tedious methods of production that were necessary to create such a complex technology.  This led to a discussion on the current research focuses within OLEDs and the possibilities of the future of OLED being introduced to the everyday household.  Subsequently, we delved into the industry itself, and highlighted a few notable products and applications that the OLED industry is involved in.  Now, we will finally take a close look at what makes an OLED what it is and the underlying principle that allows it to emit light.  After all, we’re interested in just how it identifies itself as a light emitting diode.  In this post, we will explain just how an OLED generates light and makes it such a potential powerhouse technology that we will no doubt look forward to in the future.

The placement of the heterojunction within an OLED

As we stated earlier, the typical OLED structure is composed of layers of organic material between two electrodes which are all deposited on a substrate.  The layers of organic material are considered semiconductors.  This is due to the delocalization of electrons and the structure of the organic molecules; they are electrically conductive throughout the molecule.  What results are levels of conductivity ranging from insulators to conductors.  Like all other molecules, organic material is full of unoccupied molecular orbitals.  In this case, the highest occupied molecular orbital (HOMO) and the lowest unoccupied molecular orbital (LUMO) are two orbitals most similar in energy.  The energy difference between the HOMO and LUMO is known as the HOMO-LUMO gap and allows electrons to move freely within the diode.

 The first OLED was devised by J.H. Burroughes in 1990.  It consisted of a single organic layer of polyphenylene vinylene, a popular conducting polymer.  However, as OLED technology began to evolve, it became clear that a single layer did not provide the efficiency desired.  Thus, contemporary OLEDs now contain two or more layers, usually a conductive layer with an emissive layer.  Further information about this specific structure and the materials used in its production can be found in Blog 2.  The most recent levels OLED efficiency (19%) was achieved by utilizing a graded heterojunction.  A heterojunction is an interface between two layers of semiconductor, such as the organic material being used in the OLED.  The unequal HOMO-LUMO band gaps of a heterojunction allows for greater operating frequencies as well as a high forward gain.  Additionally, the heterojunction structure allows for the hole and electron-transport materials to vary within the emissive layer.  This improves charge injection and balances charge transport at the same time.

In blog 2, we briefly mentioned the purpose of the anode and cathode within the structure of the OLED.  When a voltage is applied across the OLED, a current of electrons begins to flow through the device from the cathode to the anode.  During this process, electrons are injected into the LUMO of the cathode and ejected from the HOMO of the anode.  This can also be described as the injection of electron holes into the HOMO.  As described earlier, an electron hole is the theoretical opposite of an electron and describes a local where an electron can exist.  The ejected electron from the anode is now an electron hole.  Afterwards, electrostatic forces within the OLED bring the electrons and the electron holes together to form anexciton near the emissive layer.  An exciton is considered condensed matter that is able to transport energy without affecting the net electrical charge.  Electrons and electron holes are both fermions with half integer spin.  When they combine to form an exciton, it can be in a singlet or triplet state.  The decay of the singlet state exciton produces the light we see.

A graphical representation of how OLEDs emit light

As mentioned in blog 2, indium tin oxide (ITO) is a popular anode because it is transparent to visible light, high work function, and electrical conductivity.  This reduces the energy required for hole injection within the HOMO.  On the cathode side, barium and calcium are often used due to their low work functions which allows for an easier injection of electrons into the LUMO.  The materials chosen for the anode and cathode for an OLED are fundamental in reaching high efficiency, performance and extension of lifetime.  Thus, it is vital to produce as smooth as possible anode surface to increase adhesion, decrease electrical resistance and reduce dark spots.  While procedures to decrease anode surface roughness have been developed, potential alternate substances for the anode/cathode are also being researched.  Current candidates include single crystal sapphire substrates treated with gold.

The process in which the OLED emits light is the essence of why they exist. This method is simply unrivaled and and absolutely original in regards to anything else in the technology sector, and it brings such a unique and supreme performance experience that the OLED market is predicted to soar to unimaginable heights. It would be unwise to hazard a guess at what holds for the future for such a limitless concept. Over the course of our series covering the OLED technology, we have touched hands with all corners of chemistry, ranging from electrochemistry to organic chemistry and even ventured slightly into materials science.  We hope that by covering such an integral part of the evolving nature of the industry, we have sparked your interest in the technology revolution that has taken over the world. The current rate of innovation requires constant learning in order to stay up to date with each modification.   As Arthur C. Clarke once said, “Any sufficiently advanced technology is indistinguishable from magic.”  OLED technology has the potential to become that magic.

The Rise of Nanotechnology in Modern Lithium-ion Powered Devices

With the plethora of electronic devices being used today, the problem of battery conservation is a hot topic. People have become extremely reliant on their electronics, particularly their mobile phones. Mobile devices are easy to carry around, but charging them when they run out of battery is not always very convenient. Especially for people that move around every day for work or school, it is often difficult to find a reliable power source. Even for those that are at home all day, a short battery life can be disadvantageous. As a result, companies always work towards extending the battery life of their electronic products. It is also an important piece of information that consumers always look out for when purchasing electronics.

Many innovative advancements have already been made towards creating better and more efficient batteries. Cell phones use lithium ion batteries, so it is important to focus on improving them. Recently, a Silicon Valley-based tech company called Amprius developed a new lithium-ion battery that stores 20% more energy than batteries that are currently on the market. Amprius has already started shipping these batteries to smartphone companies, and has also secured $30 million to develop the next wave of batteries that could potentially store 50% more energy than existing batteries.

The lithium-ion batteries developed by Amprius have a silicon anode instead of the standard graphite material. Silicon anodes open new doors in terms of energy density; only four lithium ions are needed to bond with a silicon ion, while six carbon atoms are required to bond to a lithium ion. Unfortunately, creation of silicon-based batteries is currently difficult because the silicon expands and contracts from lithium ion flow with every charge/discharge cycle, thereby destroying the anode very quickly. To get around this, Amprius has developed a carbon-coated silicon nanoparticle cathode (diagram on right). Although this silicon-carbon cathode does not have the energy density that pure silicon has, but it still significantly improves battery life and can be produced with existing equipment, which is a big concern in the tech industry. These batteries will retain 80% of their charge after 500 cycles, which is more than sufficient for mobile devices.

At the Lawrence Berkeley National Laboratory, researchers have developed a new lithium/sulfur cell that boasts better energy storage, power, recharge speed, and survivability. Li/S batteries have high energy capacity because two electrons are produced every time the battery’s chemical reaction occurs.

A basic Li/S battery cell contains a lithium anode, a carbon-sulfur cathode, and an electrolyte that lets lithium ions pass through. The discharge reaction converts lithium metal in the anode into Li2S at the cathode. The flow of the two lithium ions is balanced by the flow of two electrons between the battery contacts, which deliver double the current of those in a typical lithium-ion battery.

However, there are also many issues involved in the chemistry of lithium/sulfur batteries. When the sulfur in the cathode absorbs lithium ions, the Li2S has double the volume of the original sulfur. This creates mechanical stress and deterioration, reduces electrical contact between the carbon and the sulfur, and prevents lithium ions from flowing to the surface. In addition, lithium and sulfur generally do not directly form Li2S, and require a series of intermediate species.

In response to these problems, the Lawrence Berkeley research team has developed a sulfur-graphene oxide nanocomposite cathode that is held together with an elastic polymer binder. Thin flakes of graphene oxide are coated with a layer of sulfur a few nanometers in thickness, and then a layer of protective surfactant. The electrolyte was also modified to produce an overall balanced combination that has the features for efficient Li/S cell operation.

There are a large variety of possibilities in the field of lithium ion battery improvement. Research has already produced very efficient models, such as combinations with silicon and sulfur. Lithium ion batteries are the future, and they will only get better.

Pons, Fleishmann, and their Cold Fusion Success

After the completion of their cold fusion success, Pons and Fleishmann went to the United States department of Energy to request more funding for further research. However, they were denied because others who had attempted to replicate their results had not been successful. Cold fusion, they concluded, was impossible and the experiment carried out by the two electrochemists was flawed. In the last blog post we discussed the details of the experiment, and today we will explain some theories as to why these false results were obtained.

A research team at the California Institute of Technology extensively attempted to reproduce the results of Pons and Fleishmanns experiment to no avail. They then attempted to implement different experimental errors to see if they could reproduce the same results. When the Caltech team did not put a stirrer in the tester cell, temperature differences within the cell led to false temperature recordings, which led to data that was similar to that of Pons and Fleishmanns data. These researchers at Caltech also suggested that the helium neutrons which suggested to Pons and Fleishmann that there was nuclear fusion transpiring could have simply been atmospheric traces of helium which are natural.

Some researchers also believe that Dr. Pons’ son, who helped by watching over the lab some days, might have turned off the electrical current briefly. This, Dr. Lewis of Caltech says, will cause the chemical reaction on the surface of the palladium to cease, and the excess deuterium to “bubble out” causing a fire hazard and thus, exhibited a pseudo-raise in the temperature of the cell.

Many even suggested that Pons and Fleishmann outright lied about their data. There was a great deal of mystery surrounding the experimental set-up, and the two electrochemists purposely shielded their experiment from testing and criticism by the scientific community. If you want to see for yourself how suspicious (or innocent) Dr. Pons and Dr. Fleishmann were, you can watch this video of the electrochemists at a press conference, addressing their critics. Notice how well they avoid the questions — it’s more like politics than science.

Chemistry of War: Stun Guns and Tasers

Continuing the topic of items used to incapacitate the enemy without killing them is with electricity rather than chemically. However, the proper functioning of a Taser is a direct result of the chemical properties of its materialistic components.  The word Taser and stun gun are used interchangeably. However, there are different types of stun guns or Tasers.  Some Tasers utilize properties of projectiles and therefore are more suited when an attacker is out of a victim’s arm reach. Taser is more often used for these types since it is actually an acronym for “Tomas A. Swift’s Electric Rifle”.

A typical Taser requires a 9 volt battery but the Tase Chemistry of War: Stun Guns and Tasers

The proper functioning of a Taser is a direct result of the chemical properties of its materialistic components.  The word Taser and stun gun are often used interchangeably.  However, there are different types of stun guns or Tasers.  Some Tasers utilize properties of projectiles and therefore are more suited when an attacker is out of a victim’s arm reach. Taser is the more commonly used word for these weapons. The word Taser is actually an acronym for “Thomas A. Swift’s Electric Rifle”.

A typical Taser requires a 9 volt battery but the Taser itself is still labeled as several 100kV. The increase in voltage is due to amplifiers and transformers in the Taser’s housing.  A battery is a cell that can convert stored chemical energy into useful energy. The amount of energy is calculated through two types of equations: reduction and oxidation. Reduction consists of an atom gaining electrons and oxidation is an atom losing electrons. Together the transfer of electrons produces a current. Tasers are able to have high voltages through the help of transformers to amplify the low 9 volts but voltages as high as 100kV.  However 100kV is not needed in most cases of authoritative force.

Common lithium battery is made up of -LiCO2(Lithium Cobalt Oxide) and LiC6

The reduction potential equations are:

Li+ +C6 +e– = LiC6      CoO2 + Li+ + e = LiCoO2

A high voltage does not determine how much damage a Taser can do.  Instead, it depends on the amount of current.

Tasers are effective in incapacitating the target by forcing their muscles to contract and release rapidly, causing twitching and convulsions. The human body is controlled by the brain through the use of electrical signals.  An electrical impulse can cause a muscle or group of muscles to contract or expand as necessary.  A Taser injects a foreign electrical impulse into the body and this debilitates a person temporarily (for as long as the Taser is being implemented). The act of a Taser’s current entering a human body is a result of the electron flow.  A Taser includes two parallel electrodes and two smaller test electrodes as shown in the diagram below.  When someone thinks about a Taser, the small test electrodes are probably what their minds first refer to.

As seen in the diagram, the battery offers a current that is amplified by the transformers found in the amplifier circuit.  Near the end of the Taser there are two parallel electrodes, a positively charged electrode and a negatively charged one.  These electrodes are made from a conductive metal plate.  Since these electrodes are placed along the curcuit, there is a high voltage difference between them.  Electrons want to flow between these electrodes, but they are placed too far apart, there is a gap in the circuit.  In comparison, the test electrodes are much closer together.  These smaller electrodes are used by the Taser wielder to see if the Taser is functioning.  If current is flowing through the Taser, then a small bluish, spark will jump between the test electrodes. The crackling spark is composed of air atoms that have been ionized by the electrical energy derived from the battery.  This noisy bright, crackling spark is an image that is normally associated with Tasers.  The parallel electrodes are two far apart to create a such a spark.  A Taser can inflict temporary damage on a person if their body is used to complete the circuit, or to fill the circuit gap between the two main electrodes.  Due to the potential difference in these electrodes, if a conductive object is placed between them, a large current flows.

 Additionally, there are flying Tasers that also use electrodes and a 9 volt batteries.  The main difference in the flying Taser is shown by the diagram below.  The electrodes fly out of the Taser as a projectile.  The electrodes are launched when the trigger is pulled.  The trigger opens a compressed gas cartridge and the electrodes are launched towards an attacker.

 The main risk in using a taser is found when it is used on someone who has heart complications.   Like any other muscle in the body, the heart contracts and expands due to electrical impulses, and a taser interferes with those interactions.  If someone has a weak heart, it is possible for them to die after being tased.  Tasers are weapons and, especially when used near water, can be lethal.  In 2010 a man in Hempstead died after being tased while wearing rain drenched clothing.

Due to the risk of Tasers, authoritative figures are required to use Tasers responsibly.  Here is an article describing how the some departments of the military are beginning to increase their use of Tasers. There is also a branch of authority called the Military Police.  Members of the Military police enforce the laws and regulations of the military.  In order to enforce such regulations members of the Military Police use nonlethal weaponry such as Tasers.  However, in order to encourage humane usage, military police officers are required to be hit with a Taser so they understand

Figure 5:  A picture of a military police officer being hit with a flying Taser gun.  This must be endured in order to earn the authority

r itself is still labeled as several 100kV. A battery is a cell that can convert stored chemical energy into useful energy. The amount of energy is calculated through two types of equations: reduction and oxidation. Reduction consists of an atom gaining electrons and oxidation is an atom losing electrons. Together the transfer of electrons produce a current. Tasers are able to have high voltages through the help of transformers to amplify the low 9 volts but voltages as high as 100kV are not needed in most cases.

Common lithium battery is made up of -LiCO2(Lithium Cobalt Oxide) and LiC6

The reduction potential equations are:

Li+ +C6 +e– = LiC6      CoO2 + Li+ + e = LiCoO2

Tasers function through two launching two prongs into the target. The farther apart the two prongs are, the more voltage is needed to complete the circuit. However a high voltage does not determine how much damage it does, instead it depends on the amount of current. Contact stun guns do not need a large voltage since the distance between the charge electrodes is fixed.

Tasers are effective in incapacitating the target by forcing their muscles to contract and release rapidly, causing twitching and convulsions. The human body is controlled by the brain through the use of electrical signals.  An electrical impulse can cause a muscle or group of muscles to contract or expand as necessary.  A Taser injects a foreign electrical impulses into the body and this debilitates a person temporarily (for as long as the Taser is being implemented). The act of a Taser’s current entering a human body is a result of the electron flow.  A Taser includes two electrodes and two smaller test electrodes as shown in the diagram below.  When someone thinks about a Taser, the small test electrodes are probably what their minds first refer to.

As seen in the diagram, the battery offers a current that is amplified by the transformers found in the amplifier circuit.  Near the end of the Taser there are two parallel electrodes a positively charged electrode and a negatively charged one.  These electrodes are made from a conductive metal plate.  Since these electrodes are placed along the surface, there is a high voltage difference between them.  Electrons want to flow between these electrodes, but they are placed too far apart, there is a gap in the circuit.  In comparison, the test electrodes are much closer together.  These smaller electrodes are used by the Taser wielder to see if the Taser is functioning.  If current is flowing through the Taser, then a small bluish, spark will jump between the test electrodes. The crackling spark is composed of air atoms that have been ionized by the electrical energy derived from the battery.  This crackling spark is an image that is normally associated with Tasers.  The parallel electrodes are two far apart to create a spark.  A Taser can inflict temporary damage on a person if their body is used to fill the circuit gap between the two main electrodes.  Due to the potential difference in these electrodes if a conductive object is placed between them, a large current flows.

Additionally, there are flying Tasers that also use electrodes and a 9 volt battery.  The main difference in the flying Taser is sown by the diagram below.  The electrodes fly out of the Taser as a projectile.  The electrodes are launched when the trigger is pulled.  The trigger opens a compressed gas cartridge and the electrodes are launched towards an attacker.

The main risk in using a stun gun is if the target already had heart problems and the shock is applied near the chest which can lead to cardiac arrest and/or death.

Here is an article of the military more recently starting to use stun guns. There is also a branch of authority called the Military Police.  Members of the Military police enforce the laws and regulations of the military.  In order to enforce such regulations members of the Military Police use nonlethal weaponry such as Tasers.  However, in order to encourage humane usage, military police officers are required to be hit with a Taser so they understand.