DEATH BY OXALIC ACID

Anant Babu Marahatta
Tohoku University, Japan

Oxalic acid is a constituent of many house hold products. It is found in many disinfectants, household bleach, metal cleaning liquids, antirust products and furniture polishes. Oxalic acid is a crystalline, colorless substance and is efflorescent. This means it tends to become powdery on account of loss of water of crystallization. It has got its name from the Greek word Oxalis, which means sorrel. It occurs in sorrel plant and because of this the French chemist Lavoiser in 1787 named it as Oxalic acid. It occurs in the leaves and young stalk of Rhubarb, Spinach and even Cabbage. Sorrel is succulent acid herb used in salads.

Accidental poisoning has been known to occur after a hearty meal of rhubarb or sorrel. Food rich in oxalate can also lead to kidney stones because kidney stones are generally made up of oxalates. Crystals of oxalic acid are similar in appearance to those of magnesium sulphate (Epsom salt) and zinc sulphate. Because of this similarity, cases of accidental poisoning have occurred. Magnesium sulphate in doses of 15g is used as a laxative (to facilitate the evacuation of Bowels) and is non toxic. Since oxalic acid, a dangerous poison is so similar looking to Epsom salt-a commonly used drug as laxative medicine-it is necessary to be able to differentiate between the two. If the doctor or nurse fails to differentiate between the two, accidental poisonings may occur. Two patients at the mental hospital in Scotland had died in 1956 after receiving doses of oxalic acid which was mistaken for Epsom salts. Similarly zinc sulphate is also commonly used drug and looks very similar to the dangerous poison, oxalic acid. Thus in order to remain in the safe side, it is very much essential to be able to differentiate between them.

HOW DO DOCTORS DIFFERENTIATE BETWEEN THE TWO?

Computational Chemistry

Anant　Babu Marahatta

Ph.D. student in chemistry
Tohoku University
Japan












Perspectives:

In the real world, “A Digital Laboratory could eventually mean that most chemical experiments are conducted inside the silicon chips instead of the glassware of laboratories. Turn off that Bunsen burner; it will not be wanted in ten years.” This intension of the “1998 Chemistry Nobel Prize Awardees” directed the computational procedures for conducting cutting-edge research. In the present condition, computational procedures have become a “superstar”. 

Overview: Computational chemistry is a branch of chemistry that uses principles of computer science to assist in solving chemical problems. It is simply the application of chemical, mathematical and computing skills to the solution of interesting chemical problems.

It uses computers to generate information such as properties of molecules, simulated experimental results, displays almost all the information with the chemical visualization package developed by considering the results of the theoretical chemistry.

Computational chemistry has become a useful way to investigate materials that are too difficult to find or too expensive to purchase. It also helps chemists to make predictions before running the actual experiments so that they can be better prepared for making observations.

Similarly, it can predict unobserved chemical phenomena of the macro molecules like amino acids, protein, DNA, enzymes etc. in the visual form. The following animation has explained about the preliminary processes of molecule modeling, electron density tracing and some prerequisites of the computational chemistry.

To calculate the structures and properties of molecules and solids computationally, several computer software have been developed. Some of the common software includes,

• Gaussian xx, Gaussian 09 currently [Gauss. Inc. USA]
• GAMESS [Gordon research group, Iwa state Univ.]
• MolPro, 2010.1 currently [H.-J. Werner and P. J. Knowles]
• DFTB+ [Bremen Center for Computational Materials Science]
• MOPAC [Stewart Computational Chemistry ]
• Spartan [Spartan Chemical Company, Inc.]
• Sybyl [Tripos, a Certara company]
• SIESTA[Spanish Initiative for Electronic Simulations with Thousands of Atoms]

The employed computational methods rely on the software installed and can cover both static and dynamic situations. In all cases, the computational time and other resources (such as memory and disk space) increase rapidly with the size of the system being studied. That system can be a single molecule, a group of molecules, or a solid. In order to perform the calculation in an efficient way with extremely low computational cost, proper selection of the computational method is mandatory.