1. Hydrogen and it’s applications
in biological system,
pharmaceuticals and others.
Prepared By:
Nahid Hasan
ID:1310690646
North South University
Bangladesh.
2. Hydrogen
Hydrogen is a colorless, odorless gas that burns and can form an explosive mixture
with air. It is currently manufactured from methane gas, but is also produced by the
electrolysis of water and aqueous salts. The gas is used to make such key materials as
ammonia, cyclohexane and methanol, which are intermediates in the production of
fertilisers, plastics and pharmaceuticals. Some see hydrogen gas as the clean fuel of
the future - generated from water and returning to water when it is oxidized. Hydrogen-
powered fuel cells are increasingly being seen as pollution-free sources of energy.
History:
In the early 1500s the alchemist Paracelsus noted that the bubbles given off when iron
filings were added to sulfuric acid were flammable. In 1671 Robert Boyle made the
same observation. Neither followed up their discovery of hydrogen, and so Henry
Cavendish gets the credit. In 1766 he collected the bubbles and showed that they were
different from other gases. He later showed that when hydrogen burns it forms water,
thereby ending the belief that water was an element. The gas was given its name hydro-
gen, meaning water-former, by Antoine Lavoisier.
In 1931, Harold Urey and his colleagues at Columbia University in the US detected a
second, rarer, form of hydrogen. This has twice the mass of normal hydrogen, and they
named it deuterium.
3. Natural abundance:
Hydrogen is found in the sun and most of the stars, and is easily the most abundant
element in the universe. The planet Jupiter is composed mostly of hydrogen, and there
is a theory that in the interior of the planet the pressure is so great that metallic
hydrogen is formed from solid molecular hydrogen. On Earth, hydrogen is found in the
greatest quantities in water, but is present in the atmosphere only in small amounts -
less than 1 part per million by volume. Hydrogen is prepared commercially by several
methods; manufactured from methane gas, electrolysis of water and aqueous salts.
4. Some basic information about hydrogen are mentioned in the table
below:
Origin of the name The name is derived from the Greek 'hydro' and 'genes'
meaning water forming.
Allotropes H2
Group 1
Period 1
Block s
Atomic number 1
State at room
temperature
Gas
Electron configuration 1s1
Melting point -259.1 o
C, -434.38 o
F, 14.05 K
Boiling point -252.879 o
C, -423.182 o
F, 20.271 K
Density (kg m-3
) 89 (6 K)
Relative atomic mass 1.008
Atomic radius, non-
bonded (Å)
1.100
Covalent radius (Å) 0.32
Electron affinity (kJ
mol-1
)
72.743
Electronegativity
(Pauling scale)
2.200
Ionization energies
(kJ mol-1
)
1st
-1312.049
5. Electronic configuration of Hydrogen:
1s1
Isotopes of hydrogen:
Isotopes Name Atomic mass Natural
abundance
(%)
Half life
1
H Protium 1.008 99.988 -
2
H Deuterium 2.014 0.012 -
3
H Tritium 3.016 - 12.31y
6. Importance of hydrogen bonding:
Hydrogen bonding is important in many chemical processes. Hydrogen bonding is
responsible for water's unique solvent capabilities. Hydrogen bonds hold
complementary strands of DNA together, and they are responsible for determining the
three-dimensional structure of folded proteins including enzymes and antibodies.
Water:
A simple way to explain hydrogen bonds is with water. The water molecule consists of
two hydrogens covalently bound to an oxygen. Since oxygen is more electronegative
than hydrogen, oxygen pulls the shared electrons more closely to itself. This gives the
oxygen atom a slightly more negative charge than either of the hydrogen atoms. This
imbalance is called a dipole, causing the water molecule to have a positive and negative
side, almost like a tiny magnet. Water molecules align so the hydrogen on one molecule
will face the oxygen on another molecule. This gives water a greater viscosity and also
allows water to dissolve other molecules that have either a slightly positive or negative
charge.
7. Protein Folding:
Protein structure is partially determined by hydrogen bonding. Hydrogen bonds can
occur between a hydrogen on an amine and an electronegative element, such as
oxygen on another residue. As a protein folds into place, a series of hydrogen bond
"zips" the molecule together, holding it in a specific three-dimensional form that gives
the protein its particular function.
DNA:
Hydrogen bonds hold complementary strands of DNA together. Nucleotides pair
precisely based on the position of available hydrogen bond donors (available, slightly
positive hydrogens) and hydrogen bond acceptors (electronegative oxygens). The
nucleotide thymine has one donor and one acceptor site that pairs perfectly with the
nucleotide adenine's complementary acceptor and donor site. Cytosine pairs perfectly
with guanine through three hydrogen bonds.
Antibodies:
Antibodies are folded protein structures that precisely target and fit a specific antigen.
Once the antibody is produced and attains its three-dimensional shape (aided by
hydrogen bonding), the antibody will conform like a key in a lock to its specific antigen.
The antibody will lock onto the antigen through a series of interactions including
8. hydrogen bonds. The human body has the capacity to produce over ten billion different
types of antibodies in an immunity reaction.
Chelating:
While individual hydrogen bonds are not very strong, a series of hydrogen bonds is very
secure. When one molecule hydrogen bonds through two or more sites with another
molecule, a ring structure known as a chelate is formed. Chelating compounds are
useful for removing or mobilizing molecules and atoms such as metals.
Biological importance of Water (a hydrogen containing
molecule):
Water, the most abundant compound on the planet, is a material which is essential
for all living organisms. Its uses in all living things cover a huge variety of everyday
functions which are immeasurably important to the continuity of the organism. The fact
that water makes up between 60 and 95 percent of all living organisms speaks for itself
on the incredible biological importance of this compound.
One of the major functions of water in living organism is its use as a solvent. Because
water is slightly ionised, other polar molecules such as salts, sugars and amino acids
will dissolve readily in water. This allows water to be used for the transportation of such
substances (notably in the bloodstream of animals and the xylem and phloem vessels
9. found in plants). Water can be used in this way to transport many substances: nutrients,
excretory products (eg urea, ammonia), hormones and digestive juices can all be
transported by using water as a solvent. Molecules such as starch and glycogen which
are hydrophobic are not soluble and therefore are ideal for storage.
In the digestive system many polymers and dimmers need to be broken down into
smaller molecules by the process of hydrolysis. Water is used in hydrolysis reactions to
separate the larger molecules into smaller ones (eg proteins into amino acids). Water is
produced in respiration and this water can be very useful for organisms living in dry
habitats. The process of photosynthesis requires water in order to create glucose.
The fact that water has an unusually high specific heat capacity makes it a very
useful substance for living organisms. Water does not change temperature very easily
and therefore minimizes fluctuations in temperature in cells and creates a remarkably
constant sea temperature for aquatic organisms.
Water has a high latent heat of vaporisation which means that when animals sweat
and plants transpire water, takes energy from the organism when it evaporates and as a
result cools the organism.
10. Ice is less dense than water and so in cold conditions, ice will float on bodies of
water. This insulates the water below and allows aquatic life to live in subzero
conditions.
Because water is a polar molecule, molecules of water stick together with hydrogen
bonds. This allows long chains of water molecules to stick together – this is useful both
for sucking up water through tall trees by transpiration and for creating surface tension
which allows many animals to walk on water.
Water is essential for support in plants. By the process of osmosis, plant cells take
water in which causes an increase in the pressure against the rigid cell wall – the cell
enters a state of turgor. This allows herbaceous plants to remain upright.
In conclusion, water has uses in all organisms – from plants to animals and can offer
a great many things from transport to support. This substance is absolutely essential to
the existence of every living organism on this planet.
11. Hydrogen containing pharmaceutical preparations and their
uses:
Hydrogen peroxide (H2O2):
Preparation: Hydrogen peroxide solution U.S.P. contains, in each 100 ml, not less than
2.5 g and not more than 3.5 g of H2O2.
Uses: According to the Centers for Disease Control and Prevention, hydrogen peroxide
can be used as a disinfectant to clean wounds. This can reduce the risk of contracting a
bacterial infection. Hydrogen peroxide also stops small vessel wound bleeding, and it
can be used in oral hygiene as well.
Sodium bicarbonate (NaHCO3):
Preparation: Sodium bicarbonate U.S.P. is a highly water soluble antacid with a very
rapid onset of action but relatively short duration. It causes a sharp increase in gastric
pH up to above pH 7.
Uses: According to the GI Care website, hydrogen is also a key ingredient in sodium
bicarbonate. Sodium bicarbonate is found in both salt and baking soda. However, it is
also used as a method of treating certain conditions due to its power to neutralize
acidity. For example, sodium bicarbonate is used to treat medical conditions such as
ulcers, hyper-acidity in the digestive track, kidney stones, swelling of the face or any
other part of the body, high blood pressure and heart disease
12. Boric acid (H3BO3):
Preparation: It is produced from borax by reacting with hydrochloric or sulfuric acid.
Uses: A buffer and a very weak germicide. Its nonirritating properties make its solutions
suitable for application to such delicate structures as the cornea of the eye. Aqueous
solutions are employed as an eye wash, mouth wash, and for irrigation of the bladder.
Hydrochloric acid (HCl):
Preparation: By the interaction of NaCl and H2SO4 or by combing chloride with
hydrogen.
Uses: Officially classified as a pharmaceutical aid that is used as an acidifying agent .
Used in achlorohydria.
Phosphoric acid (H3PO5):
Preparation: Phosphorus is converted to P2O5 by exposing it to a current of warm air,
then the P2O5 is treated with water to form the phosphoric acid.
Uses:
To make dilute acid and as a weak acid in various pharmaceutical preparations.
Industrially, it is used in dental cements and in beverages as an acidulant.
13. Hydrogen sulfide:
Uses: According to Physorg.com, hydrogen sulfide is frequently used in emergency
medicine. When hydrogen sulfide is administered to patients who are undergoing
cardiac surgery, it helps aid in healing and can reduce the effects of some heart
problems. During a medical emergency such as myocardial infarction, a patient may be
administered hydrogen sulfide directly into the heart during the surgery. Patients who
are administered this shot experience an increased oxygen supply to the heart, which
helps resuscitate it. Hydrogen sulfide can also help the heart by reversing the ill effects
of reperfusion. Reperfusion is an undesirable byproduct of the process by which blood
flow is restored into the heart. Reperfusion occurs when, after a period of inactivity
during which the heart isn't receiving significant blood flow, a sudden return of blood
causes inflammation and excess stress.
Deuterium:
Uses: Deuterium oxide (D2O) has been used as a research tool in biological and
pharmacological investigations. Use of deuterium oxide for drinking purposes has
caused retardation or stunted growth in experimental mammals. It is available
commercially and finds use as a moderator in nuclear reactors and as a solvent in
nuclear magnetic resonance studies.
14. Tritium:
Uses: According to the Better Health website, tritium is one of the isotopes of hydrogen.
This substance is used as a marker in the medical industry. A "marker" is a term that
refers to test results that act as diagnostic tools. For example, a tumor marker refers to
the levels of certain chemicals in the blood that doctor's use to determine how large a
tumor is. Tritium, a highly radioactive material, is used extensively in X-rays and other
kinds of medical imaging, to identify these tumor markers. As a result, it is one of the
core ingredients in nuclear medicine.
Other uses of hydrogen:
Fertilizer: The most important use of hydrogen is the ammonia (NH3) synthesis. This is
used to make fertilizers.
Petroleum:
Hydrogen gas is used in the processing of petroleum products to break down crude oil
into fuel oil, gasoline and such.
Rockets:
Since hydrogen is highly flammable, especially when mixed with pure oxygen, it is used
as a fuel in rockets. Usually, they combine liquid hydrogen with liquid oxygen to make
an explosive mixture.
15. Unfortunately, in 1986, the U.S. Space Shuttle Challenger exploded when a flame
accidentally ignited the liquid hydrogen in an external fuel tank. This again showed that
the gas can be dangerous and cause a disaster in some situations.
Clean fuel for cars:
Hydrogen is one of the cleanest fuels because when it burns, the result is simple water.
That is why there are efforts to create engines that can power automobiles on hydrogen.
This would greatly help to reduce the air pollution and global warming problems.
Hydrogen the lightest of all elements but very much useful for all the life forms in the
world. The biological importances of hydrogen bond and water have been described
above. Various forms and derivatives of hydrogen are used for many purposes in
medicine. Some of them have mentioned. There are many more uses that we have
discussed. The smallest but an amazing element of periodic table.
16. References:
1.Book: Remington:The science and practice of Pharmacy, Edition-20th
,Author-Alfonso R
Gennaro, Ara H Der Mardersian, Glen R Hanson, Thomas Medwick, Nicholas G popovich,
Roger L Schnaare, H Steve White, Publisher-Lippincott Williams & Wilkins.
2.Book: Inorganic Medicinal and Pharmaceutical Chemistry, Edition-1st
, Author-John H. Block,
Edward B.Roche, Taito O.Soine, Charles O. Wilson. Publisher-Varghese Publishing House.
3. http://classroom.synonym.com/importance-hydrogen-bonding-2514.html .Date-22/11/13
4. http://www.ehow.com/list_6019214_medicinal-uses-hydrogen.html.Date-22/11/13
5. http://www.rsc.org/periodic-
table/element/1/hydrogen?gclid=CNnMipei3roCFeE34godUx8ALQ.Date-22/11/13
6. http://www.school-for-champions.com/chemistry/hydrogen_uses.htm#.UpFudcQy0so.Date-
22/11/13