Nanotechnology: working at the scale of atoms

Nanotechnology works with materials at the scale of nanometres, billionths of a metre, where materials can behave differently from their bulk forms: stronger, more reactive, or able to carry drugs to particular cells. A nanoparticle of a familiar material may have a far larger surface area for its size, which changes how it reacts chemically and how it moves through the body or the environment. That change in behaviour is the scientific reason the field attracts both excitement and caution.

India's Nano Mission, launched by the Department of Science and Technology in 2007, funded research centres, training and infrastructure for nanoscale science. Its work spans nanoelectronics, nanomaterials, nanomedicine and water treatment, among other applications. In medicine, researchers explore nanoparticles that deliver drugs more precisely or improve imaging; in energy, nanomaterials are studied for batteries, solar cells and catalysts; in water, nano-filters are tested for removing contaminants.

The promise has to be weighed against measurement and safety problems. Nanoparticles are hard to detect and track in the environment, and their toxicity can depend on size, shape, coating and dose, not only on chemical composition. A material that is safe in bulk form cannot automatically be assumed safe as a nanoparticle, and a nanoparticle that works in a laboratory may behave differently in soil, water or the human body. Regulators therefore face a moving target: the same novelty that creates new uses also creates new uncertainties.

Commercial use is still uneven. Many nano-enabled products, such as coatings, sunscreens and composites, are already on the market, while more ambitious applications, such as targeted cancer therapy or large-scale water purification, remain largely at research or trial stages. The gap between laboratory demonstration and affordable product is familiar from other technologies, and it is widened by the need for specialised fabrication and testing facilities.

For civil studies, nanotechnology is a good example of an emerging technology where governance must run ahead of harm without strangling research: fund the science, build measurement and safety capacity, require clear labelling and risk assessment for products that reach people, and keep public discussion open about uses that affect health and the environment.