nanograms

A nanogram (ng) is a unit of mass in the metric system, equal to one billionth of a gram (10^-9 g). It is a derived metric unit formed from the gram using the nano- prefix, and the SI base unit of mass is the kilogram.

In practical terms, 1 ng equals 10^-12 kilograms, and 1 microgram (µg) equals 1000 ng, while 1 nanogram equals 1000 picograms (pg).

Nanograms are used to express very small quantities in chemistry, biology, medicine, and environmental science. They are common in measurements of DNA, RNA, proteins, trace drugs or toxins, and nanoparticles, where precision is essential.

Measuring such small masses requires high-sensitivity equipment, including analytical balances, microbalances, or mass spectrometers. In routine practice, mass measurements at the ng scale are supplemented by concentration measurements and calibration to ensure accuracy.

The nano- prefix denotes a factor of one billionth. The term nanogram has been in use since the 20th century with the growth of nanotechnology and molecular biology.