Nano silver to tackle microbial contamination
In view of continued microbial contamination of bugs and super bugs that are resistant to ordinary antibiotics, it has become necessary now to kill the microbes viz, viruses, bacteria, fungi either physically or chemically.

A fungal antimicrobial coating has been developed by Singapore based Nanyang Technological University which kills about 98 per cent of the microbes as claimed by the scientists. The chemical is di-methyl desyl ammonium chitosene methacrylate. This chemical coating contains sponge like particles that are positively charged that attract the negatively charged particles in microbes. The interaction of this attracts the bacteria and in the process the bacteria are destroyed.

It is recommended in hospitals to sterilize catheters, implants etc. It can be used for domestic equipment with no danger to humans. It is claimed that this chemical can be used to replace antibiotics.

But what is important is that microbes in course of time are likely to develop resistance since it is likely to kill 98 per cent. The balance two per cent  can become resistant. Hence it is advisable not to use chemicals and the best choice is Nano silver that kills 100 per cent of microbial contaminants in bacteria, viruses, fungi etc. Nanosilver of 150 – 400 nanometres is far superior to tackle the problem of microbial resistance. Nano silver is cheaper than the chemical.

The world of nanotechnology is totally different: sitting in a chair that self adjusts to suit our posture, wearing a shirt to measure body temperature and heart rate.

Ultra hydrophobic surface coatings are produced using nano particles and poly electrolytes which are non wetting, self cleaning that can be used for car window screens, textiles and exterior surfaces.

Nano composites of polymer containing carbon nano tube can be used as shock proof and sound proof functions.

Materials containing nano particles change colour depending on the size of particle. Some composites change colour with applied voltage and are called electro-chrome materials.

Nano particles of different materials are being produced for use as coatings, catalysis and non-linear optics. Nano tubes, nano wires and nano belts have the excellent features for carrying change.

Based on bottom up approach, nanotechnology can lead to the most efficient utilization of mass and energy.

Nanotechnology is defined as the science of dealing with atoms only a few nanometers in dimension. When the size of object is scaled down to the nano-material range, the properties of materials undergo transformation that has very high potential in various spectrum of human activity, thus making it as the most potential technology which as tremendous implications in computers – a billion times more powerful than what we have achieved so far. The market is expected to cross US$ one trillion  by 2015.

Indian scenario presents considerable activity with a wide spectrum of products – MEMS, NEMS, nanostructure synthesis and characteristics, biochips or lab-on-a-chip concepts, Nano-electronics (CNT, Nano-particles), Nano-powders, and Nano composts. Most of the ongoing research works are  financed and co-ordinated by DST, MEIT and DBT and other government agencies in collaboration with the already established two centres of excellence of IISC Bangalore and IIT Mumbai.

Objectives:

• Systematic development of innovative products for application in diverse spectrum of human activity like electronics, semi conductors, medical and health and environment in a phased manner by identified technologies up-scaled for manufacture.
• Strengthening of modular aspects of nano biotechnology with special focus on the microbial synthesis of nano materials – metals – inorganic etc,
• Networking with relevant manufacturing industries in India and abroad for a symbiotic promotion.
• Collaboration with various agencies / industries of relevance.

Micro-organisms as the source for nano materials
Micro-organisms are continuously and constantly exposed to stressful situation and their survival depends upon the ability of resistance. Microbes when subjected to high metal concentrations, induction of resistance is brought in by specific mechanisms like efflux systems, alterations in solubility and toxicity changes in redox state of metal ions, extra cellular complexation or precipitation of metals.

Thus the metal microbic interactions have an important role in the commercial biotechnology applications like bioremediation and biotechnology. Materials such as metals, metal oxides or metal sulfides are widely used for the transformation of physical properties with the size reduction to nano-material range and these nano materials have a wide range of application in microelectronics, optoelectronics, magneto-electronics and biomedical systems.

Products of Nanotechnology  in various sectors of human activity spectrum covers medical and health, environment, remediation of air and water etc.

1. Medical sector:
A) Diagnostics:

• Detection of diseases
• Replacement of fluorescent dyes
• Contrasting agents
• Lab – on – a – chip system
• Detection of prostrate cancer by calcium selenide

B) Therapeutics

• Chronic lymphocyte leukemia – B Cells utilize monoclonal antibodies with Au/Ag nanos against VEGF.
• Photodynamic therapy utilizing nano gold (20 nm) coated monoclonal antibodies conjugated to Ab/peptide to get attached to cancer cells. On irradiation with infra red laser gold nanos get heated killing the cells.

C) Preventive medicine

• Human monoclonal antibodies against gp120 antigen of HIV 1 incorporated with silver nano (1-10 nm) kills the virus before entry into the body. Application usage in uterine gels.

b) Vaccines etc.,

• Nasal vaccines against HIV, Herpes and other viruses, E Coli, Salmonella, Anthrax viruses and Fungi candida albicans.
• Nano emulsions
• Nanogels agents

D) Medical textiles / hospital care:
Surgical gauze, wound dressing, surgical masks, gloves, self sterilized hospital gowns and beddings.

Wound management:
Burns, ulcers, toxic epidermal necrolysis, master skin grafts and donor sets.

• Medical devices / surgical equipment:
• Catheters, surgical implants, artificial joints, bones, pins, heart valves, endovascular stunts, urological stunts, endotracheal tubes, infusion ports, orthopaedic fixation devices and endoscopes.
• Prevention of neonatal distress syndrome in the neonates by prevention of surface tension.

4 Topical application:

• Anti -infection powders
• Nano silver emulsions e.g.: E Coli, Salmonella, Anthrax
• Herpes and HIV 1
• Fungicides: Candida albicans
• Coating on cloth, bandages, wound dressings
• Gauze Cotton, Catheter
• Anti infection powders.

Transit delivery of drugs:
Folic acid, dendromeres, pharmaceuticals, cholesterol lowering drugs, Cachexia  and anti emetic.

• Bioavailability of drugs, nano drugs, nano drug solutions, water & fat soluble nano drugs in solution.

Food supplements
Fat soluble A, D, E, K vitamins, beta carotene, coenzyme Q 10, Lutein, alpha lipoic acid, Isoflavone water insoluble items become soluble and bio-available by chemical modules.  

• Nano particles in medicine in various fields like design, manufacture, administration monitoring some of the nanos unlike macro or micro molecules exhibit properties like strength, electrical conductivity & colour etc.,  

• Drug delivery system sprays, replacing infusions.  

a)    improvement in cold storage of food (food security)  
b)   Stain resistant cloth  
c)   Drinking water sterilization (10 – 20 nm)

11. Topical  

• Ag 150 – 400 nm
• Anti-infection powder  
• Bacteriocide   
• Nasal vaccines   
• Nano-emulsion gels against E. coli, Salmonella    
• Viruses – HIV / Herpes    
• Fungi – Candida albicans, Anthrax sps.

Pharmaceuticals (Nanoceuticals): Pharmaceuticals consist of lipophilic components with poor bioavailability and poor dissolution surrounded hydrophilic surface by small nano wet particles make the components pass the unstirred water layer of intestines and absorbed without bile and pancreatic activity. These are Vitamin A, D, E, K, beta carotene, Vitamin C (citric acid), sorbic acid, benzoic acid, Tocopherol, Isoflavone, Alpha lipoic acid, Lutein solubilized Omega 3 – fatty acids, Coenzyme Q 10.

Nanotechnology is the science of building and using materials and devices at the scale of atoms and molecules. At such a minute size , materials exhibit different properties than what they are at macro scale. It is possible to shrink hard disks, develop stain – resistant clothes and improve cold storage.
Drugs fused with nano sized carriers, smaller doses can deliver better results.

Using materials  at  scale of atoms and molecules
 A nanometer is one billionth of a meter. A human hair has an average diameter of 8,000 nm. At such atomic scales the usual rules of physics and chemistry are not applicable. The characteristics are that these nano materials differ with respect to colour, conductivity, strength and reactivity. Carbon nano tubes made out of graphite carbon have been found to be 100 times stronger than steel and 1/6 of their weight.

The application spectrum is as follows:Water filters using silver and gold nano particles that are anchored on alumina to extract Endo-sulfan, Malathion and Chloropyrifos pesticides that are found in drainage water. Using nano silver (20 – 30 nm), filters can be made to make drainage water safe. Nano parts spares can be used in neonatal respiratory diseases of newborns and even in eye drops, development of new pesticides and insecticides. Work is on to develop silicon based electronic devices.

Photodynamic therapy
Gold coated nanos (AW / 20nm) conjugation to antibodies or peptide to get attached to cancer cells. After irradiation with infra-red laser, gold nano get heated to destroy the cancer cells. Folic acid can be used dendromers for transit delivery of drugs.

Smart pharmaceuticals
Production of desired chemicals by programmable molecular fabrication in pure form couple to molecular sensors leads to flawless products with required standards with exact fidelity that makes allergic reactions and side effects extinct.

Identification and quantification of drugs:
Drug documentation will become similar to protein structural base. Health care technology will become totally different.

Diagnostic technology:
Detection of drugs in saliva / sheath lining cells.
N    Food additives – antioxidant Coenzyme Q 10. Amphiphilic, lipophilic food colourants keratin in Beverages and non fat food.
N    Food supplements / dietary supplements
a) Fat-soluble vitamins A, D, E, K
b) Beta carotene
c) Coenzyme Q 10
d) Lutein, alphalipoic acid isoflavone water insoluble actives become soluble and bioavailable without any chemical modification.

3. Cosmetics:
Amphiphilic and water and fat soluble 12 Generation of electricity when fluid is passed through a nano tube act as a nano sensor to generate small amounts of electricity and flow of gases like O2, N2. Creation of small hydro electric power station by carbon nanos.

Remediation of air pollution

• Removal of volatile organic compounds from industrial smoke stacks by manganese dioxide
• Reduction of amount of platinum used in catalytic converters
• Removal of CO2 from industrial smoke stacks using carbon nano tubes
• Removal pollutants from diesel exhausts, Silver, Platinum catalysts
• Removal of air pollutants, silver nanos embedded in Manganese oxide
• Change in the composition of concrete to reduce CO2 emissions
• 100 per cent degree reduction in operating temperature for the removal of smoke stack gases with Platinum.

Small wall nano tubes (SWNT’s) are exemplary in the fields that can act of sensors of electrical resonance changes in the presence of targeted pollutant namely, nitrogen-di-oxide.

TiO2 system used at USEPA’s site programme at the Department of Energy facility in Oakridge at USA as effectively remediate the ground water contaminants with benzene, Toulene, Ethyl benzene, Xylene, Chloroform, Ethyl benzene, Nitro benzene, TCE and MTBT.

Oxidation of organic pollutants into non-toxic materials, TiO2 system is used for environmental re-mediation because of low toxicity, high photo-conductivity, high photo stability and availability at low cost. When illuminated by light with an energy level exceeding 3.2 eV, the bond gap of TiO2 translates to light with a wavelength shorter than 387.2 nm that follow in the category of UV light.

The demand for nano materials in health care sector was 85 million US$ in 2001 in  USA for the materials used such as digitalization, imaging, pharmaceuticals, implants, prosthetics etc. Then the market rose to US$ 109 million in the year 2006. The market is expected to rise to US $ 2.60 billions  by 2014 globally. USA spent US$ 1.6 billion in the year 2010.

Thus the application of nanotechnology has tremendous potential to bring enormous changes in human civilization, in various spectrum of  human activity including medicine, agriculture, energy, space science, decrease of climate warming, cleansing of water bodies, micro-electro- mechanical industry and thermodynamics.

A team of scientists led by Dr. Ray Kurtzhecil assured that with in a span of a decade we will have the means to reprogramme our bodies’ software and continue to live indefinitely with the help of nanotechnology. Our living space and our body surfaces can be kept clean from fungal infections.
We can even eliminate microbial infections from the clothes we wear.