Gold nanoparticles when assembled in large supercrystals could detect sensitivity for chemicals in explosives or drugs.
Researchers at Sandia National Laboratories have artfully combined the principles of nanotechnology and basic chemistry to develop large supercrystals promising superior sensors. According to lead Sandia researcher, Hongyou Fan, “the supercrystals have more sensing capability than regular spectroscopy instruments currently in use, just like a dog’s nose has more sensing capabilities than a human’s.”
The benchtop sensors, recently reported in Nature Communications, also are surprisingly inexpensive, Fan says. The supercrystals comprises of a minimal amount of gold element, roughly 0.012 grams to form a sensor, thus making it cost effective. Prior researches reported the micron range development of gold supercrystals which was unfit for commercial production owing to the small quantity of its production and also the submillimeter supercrystals could be coerced with industrial tools of the macroworld.
The researchers at Sandia University formed the Sandia supercrystals by self-assembling millions of gold nanoparticles in a neat arrangement. The nanoparticles were seen to develop facets because of the pressure given during its self-assembling. These facets are responsible for recognizing and transmitting signals. The main principle for transmitting and receiving signals is based on electromagnetism.
Initially the crystals are formed by dispersing the gold particulates about 5 nanometers in diameter into a solvent, toluene. A number of other processes follows making the particles supersaturate, precipitate, and finally crystallize as small seeds. The growth of facets makes them available to respond to a wide variety of incoming chemical odors or light band frequencies. The total procedure may take a week to complete.