Overview of research in chemistry

An Overview of Research in Chemistry: Application to Biological

and Medical Sciences

Contents Chemistry & Its Branches

Chemistry in Medicine & Health care

Chemistry in Food

Use of NMR & X-ray Crystallography in Structural Biology

Application of Nuclear Chemistry

Application of Inorganic Chemistry

Application of Nanotechnology

What is chemistry?

Chemistry is the science of matter, especially its chemical reactions, but also its composition, structure and properties.

Chemistry is concerned with atoms and their interactions with other atoms, and particularly with the properties of chemical bonds.

Subdisciplines of Chemistry

Major Subdisciplines of Chemistry

Analytical chemistry

Inorganic chemistry

Biochemistry

Physical chemistry

Materials chemistry

Organic chemistry

Nuclear chemistry

Pharmaceutical Chemistry

Environmental Chemistry

Chemistry in Everyday life

There is no aspect of our life that is not affected by

developments in chemistry.

Chemistry plays a very vital role in our everyday life. Our daily need of

food, clothing, shelter, potable water, medicines etc. are connected with

chemical compounds, processes and principles.

Chemistry has important contribution for giving us:

Life saving drugs

Synthetic fibers,

Synthetic detergents

Variety of cosmetics

Preservatives for our food

Fertilizers & pesticides

Paper

Glass

Plastics

Beautiful paints etc.

Application of Chemistry in biological and Medical Sciences

Chemistry in Medicines & Healthcare

Type of Drug Its Use Example

Antipyretics Lower the temperature of body Aspirin, paracetamol, phenacetin.

Analgesics used to relieve pain naproxen, diclofenac sodium.

Antiseptics used to kill or prevent the growth of micro-organisms.

furacin, soframycin

Anticancer drugs to treat cancerous growths. cisplatin

Tranquilizers treatment of stress, mild and severe mental diseases

membutal, veronal, luminal

Antihistamines diminish the actions of histamine released in the body and hence pervent allergy.

Benadryl, Avil, foristal

Antacids neutralize acid in the gastric juice and relief from acidity, heat burns

Baking soda in water, cimetidine, rantidine.

Anesthetics produce general or local insensibilty to pain and other sensations.

Chloroform, vinyl ethers

The chemical substances used for treatment of diseases and for reducing sufferings from pain are called medicines or drugs. Some of the medicinal compounds are discussed below:

Uses of Chemistry in Practice of Medicine

Principle Involved Its Role

Electrochemistry

•Na+ ion pump •Nerve conduction and action potentials. •Electrical gradient

Gas laws and diffusion •O2 and CO2 diffusion in alveoli of lungs

Solubility

•Will certain chemicals be able to diffuse through the cell membrane i.e. lipid bilayer •How will the concentration of chemicals (drugs) be distributed through body tissues.

Kinetics

•How rapidly are chemicals we give patients degraded in the body. •Half life of drugs

Metals

•Iron-Hemoglobin and O2 transport •Copper-Immune system health •Zinc-Wound healing, smell and taste

Nuclear chemistry

•Isotopes used for imaging studies-Technetium Tc99

•Isotopes used for therapy-Radioactive Iodine I131

Chemicals in Food

Many chemicals are added to the food materials for their

preservation and enhancing their appeal. These are flavourings,

sweetners, antioxidants, fortifiers, emulsifiers and antifoaming

agents.

1. Preservatives: To prevent their spoilage and retain their nutritive value for long periods. E.g. common salt, sugar, oils, sodium benzoate, butylated hyrdroxyanisole (BHA).

2. Artificial Sweetening Agents: Give sweetening effect to the food. E.g. Saccharin (300 time more sweeter than sucrose), aspartame, dihydrochalcones.

3. Antioxidants: Prevent oxidation and subsequent spoilage of food. E.g. butylated p-hydroxy toluene, esters of gallic acid (propyl gallate), lecithin.

Use of NMR and X-ray crystallography in structural biology

Structure elucidation:

• X-ray crystallography

• NMR

P. falciparum (malaria) Dihydrofolate reductase

Human HSP90 Human HIV-1 reverse transcriptase

Nuclear magnetic resonance spectroscopy of proteins

Protein NMR is a field of structural biology in which NMR spectroscopy is used to obtain information about the structure and dynamics of proteins.

Apart from 1D technique, there are 2D techniques as well:

1H-1H COSY } short-distance info

1H-1H TOCSY } short-distance info

1H-1H NOESY } long-distance info

(plus tons of other techniques – including 3D NMR)

Each technique gives complementary information.

The blue arrows represent the orientation of the N – H bond of selected peptide bonds. By determining the orientation of a sufficient amount of bonds relative to the external magnetic field, the structure of the protein can be determined.

Application of Nuclear Chemistry in Medical

Science

Brain tumour location: o Brain tumours are difficult to locate. o We label dye that are preferentially

adsorbed by cancerous cells with 131I (diiodofluorescein or rose bengal) and scan entire space around skull by special counters.

Assessing the volume of Blood in pateint: o Sometimes necessary for surgeon to know

amount of blood in patient of anemia, severe haemorrhage in an accident.

o Isotope dilution method is used, and label 1ml of pateint ‘s blood with 24Na.

Application of Inorganic Chemistry in Medical

Science

Metal complexes in medicine

Comparison to organic-based medicines, metal complexes have more

• coordination numbers

• geometries and

• oxidation/reduction states.

Targets of metal-based medicines include DNA, protein, and enzymes.

• Metal complexes targeting DNA DNA has been the primary target of metal complexes due to the ability of cationic metal interacting with the anionic backbone of DNA. The anticancer chemotherapy drug cisplatin

covalently binds to DNA, which disrupts transcription and leads to programmed cell death.

• Metal complexes targeting enzymes and proteins Metal complexes can interact with the amino acids with the highest reduction potential (histidine, cysteine, and selenocysteine).

Platinum: Along with cisplatin, platinum complexes inhibits thioredoxin reductase and

topoisomerase I.

Gold: A drug (auranofin, a gold(I) phosphine complex) has

shown value in treating parasitic disease through inhibiting thioredoxin glutathione

reductase

Ruthenium: They have anticancer activity. And are

glutathione transferase inhibitors.

Vanadium: Oxovanadium porphyrin complexes have

demonstrated HIV-1 reverse transcriptase inhibition in vitro.

METAL COMPLEXES

Application of Nanotechnology to Medical Sciences

• Drug Delivery

Nanoparticles are used to deliver drugs, heat, light or other

substances to specific types of cells (such as cancer cells).

Particles are engineered so that they are attracted to diseased

cells, which allows direct treatment of those cells.

This technique reduces damage to healthy cells in the body and allows for earlier detection of disease.

• Anti-Microbial Techniques

Nanocrystalline silver which is as an antimicrobial agent for the treatment of wounds.

A nanoparticle cream has been shown to fight staph infections. The nanoparticles contain nitric oxide gas, which is known to kill bacteria.

• Therapy Techniques Buckyballs may be used to trap free radicals

generated during an allergic reaction and block the inflammation that results from an allergic reaction.

Nanoshells may be used to concentrate the heat from infrared light to destroy cancer cells with minimal damage to surrounding healthy cells.

Nanoparticles, when activated by x-rays, that generate electrons that cause the destruction of cancer cells to which they have attached themselves.

Nanofibers can stimulate the production of cartilage in damaged joints.

Nanoparticles may be used, when inhaled, to stimulate an immune response to fight respiratory virsuses.

References

• Fundamentals of medicinal chemistry- Gareth Thomas

• Modern abc of Chemistry- Class XII

• Essentials of Nuclear Chemistry- Arnicar

• portal.acs.org/portal/PublicWebSite/education/.../research/index.htm

• www.understandingnano.com/medicine.html

• en.wikipedia.org/wiki/Medicinal_chemistry

Thank You