Nanoparticle

In materials science, a nanoparticle is a member of a class of particles (or atomic clusters), which have average dimensions smaller than roughly 100 nm. They exhibit properties not normally associated with the bulk phase of materials, such as quantum optical effects. Because the optical properties of nanoparticles are a function of their sizes, mixtures of differently sized nanoparticles are being investigated for their ability to maximize energy conversion in solar panels. By using a variety of chemical functionalization and chemical etching techniques, their use as targeted delivery devices is increasingly being reported in the scientific literature. Magnetic nanoparticles, which can be precisely relocated within living tissues, have recently been used in a number of promising new medical procedures. Particles decorated with surface antibodies or aptamers targeting to cancer-specific proteins have also shown promise in early research studies.

Toxicology and environmental effects

Possible toxic effects of nanoparticles are not fully understood.

Life sciences applications

Manufactured nanoparticles can be used for drug delivery, mimicking the behavior of cellular components and acting as "intracellular reservoirs for sustained release of encapsulated therapeutic agent" Components include:

• vesicles
• liposomes
• micelles

They may be manufactured as:

• coated solid particles
• polymers
• solid lipid nanoparticles