The History of Nanotechnology
Synthesis, Chemical–Physical Applications
to Nanomedicine

• The prefix "nano" is a Greek prefix meaning "dwarf" or something very small, depicting one billionth of a meter 10⁻⁹ m.
• They possess unique properties like finite size, specific surface area, catalytic properties, and remarkable optical & magnetic features.
• World is shrinking and there is deep and relatively unexplored world beyond what an human eye can see. This microscopic world is truly alien and very fascinating.

Richard
Feynman

1918 - 1988  ◆  American Physicist  ◆  Nobel Laureate

• Introduced the concept of Nanotechnology in 1959.
• At the American Physical Society meeting he presented his landmark lecture "There's Plenty of Room at the Bottom" at the California Institute of Technology.
• He posed a question that would change science: "Why can’t we write the entire 24 volume of encyclopaedia at the tip of a pin?" - and envisioned machines building smaller machines down to the molecular level.
• His idea was proven correct and thus he is considered the Father of modern Nanotechnology.

• 4^th century - The Lycurgus Cup: an ancient Roman cup that shifts colour with the light - green in daylight, red when illuminated from within all thanks to Au & Ag nanoparticles 50–100 nm in a 7:3 ratio.
• Medieval church windows shine luminous red and yellow due to Au & Ag nanoparticles fused into the glass.
• Ancient Egypt: hair-dye paste of lime and lead oxide formed lead sulphide (PbS) nanoparticles - reacting with keratin sulphur for steady black dye.
• 9^th–17^th centuries: glittering "luster" ceramic glazes of the Islamic world; Italian Renaissance pottery of the 16^th century.
• 1857, Michael Faraday studied the preparation and properties of colloidal suspensions of "Ruby" gold.

After Feynman opened this new field, two approaches emerged for synthesizing nanostructures - differing in quality, speed and cost.

• Top-Down Approach: Breaking down large pieces of material to generate the required nanostructures.
• Bottom-Up Approach: Assembling single atoms and molecules into larger nanostructures.

Nano Devices

• Nanotechnology centres on opportunities for improving the efficiency, sustainability and speed of already existing devices and processors.
• It uses less material - a large proportion of which is already in a more reactive state.
• In electronics and sensors it enables components that are faster, more sensitive, use less power, and can be packed at much higher densities.
• Countless nanotechnology-based goods are already making their way from the market to end users and consumers.

Computers

• Nanotechnology has been pivotal in advancing computers leading to faster, smarter, more portable systems.
• Today it is normal for a computer to be carried in a hand although 40 years ago a computer was infinitely slower and the size of a room.
• Miniaturisation of World of microprocessors.
  Transistor size shrank from
  250 nm · 2000 to 1 nm · 2016.
• This revolution in transistor size has enabled the memory of an entire computer to be stored in a single chip.

Computing at the Nanoscale

• Hewlett Packard (HP) memory devices use nanowires coated with titanium dioxide - higher memory density than flash chips.
• Magnetic nanowires of nickel and iron alloy create dense memory devices.
• Intel moved from 65-45 nm chips to 22 nm - itself a milestone.
• Magnetic tunnel junctions enable quick, effective data transfer and efficient save-on-shutdown.
• Nanorods in displays reduce electricity consumption and heat emission.

Mobiles

• In making OLED screens, nanotechnology is extremely important - packed with nanoparticle coatings to guard against environmental deterioration.
• Nanowires as electrodes enable larger, more flexible OLED screens - flexible phones that can coil around the wrist like a bracelet.
• Nanotubes reduce panel energy consumption, weight, and thickness.
• Longer battery life, ultimate display protection, and a more powerful phone experience.

Energy

• Nanomaterials are being used to build a new generation of solar cells, hydrogen fuel cells, and novel hydrogen storage systems.
• Titanium dioxide (TiO₂) and Zinc oxide (ZnO) nanomaterials act as efficient photocatalysts for hydrogen production through water splitting.
• Nanotechnology is being used in many ways to improve energy efficiency and the use of renewable energy sources.

Fabrics

• Manufacturers are adding nano-sized components to conventional materials to improve performance.
• Water and stain repellent clothing uses nano-sized whiskers that cause water to bead up on the surface.
• Used in the manufacturing of bulletproof jackets.
• Spill-proof, dirt-resistant, antimicrobial, antibacterial, antiviral fabrics.

Nano-Bio
Technology

• Nanoparticles as therapeutics can be delivered to targeted sites - including locations not easily reached by standard drugs.
• Nanodentistry offers significant advantages in natural tooth maintenance.
• In agriculture - crop health, fertilisers, pest control, food safety, drought stress, plant breeding, photosynthesis.
• In food science - processing, packaging, functional food, safety, pathogen detection, shelf-life extension.
• In tissue engineering - nanofibers, nanopatterned surfaces to control cell behaviour, regulated release of bioactive growth factors.

Cosmetics

• Nanoparticles are used in a range of cosmetic products - face cream, face pack or mask, body lotion, perfumes, anti-wrinkle lotions, and more.
• Cosmetic manufacturers use nanosized ingredients to improve UV protection, skin penetration, colour, fragrance release, finish quality, anti-aging effect, and a variety of other properties.

Environment
Conservation

• Landfills contain plastics that take ~250 years to decompose naturally.
• Nanotechnology offers a solution - cellulose, an abundantly occurring natural polymer, yields nanocellulose - eco-friendly and sustainable.
• Used to clean outdoor air pollution - removing toxic gases and protecting people from harmful contaminants.
• Precise molecular-level sensors detect pollutants before they accumulate.

Biomedicine

• Revolutionized drug delivery - effective, targeted delivery, minimised side effects, and increased therapeutic efficacy.
• Uses minuscule materials and devices for precise drug delivery, advanced disease detection, and innovative treatments.
• Many potential benefits for cancer detection, diagnosis, and treatment.
• Nanoparticle vehicles activate the immune system to suppress cancer and induce tumour cell death - increasing neo-antigen release.
• Improve antigen presentation and T-cell activation.