Femtogram

Femtogram (fg) is a unit of mass in the International System of Units (SI) equal to 10^-15 grams. It is a submultiple of the gram, which is the base unit of mass in the SI system. The femtogram is used in fields that require measurement of extremely small masses, such as biochemistry, pharmacology, and nanotechnology.

Definition

A femtogram is defined as one quadrillionth (10^-15) of a gram. The prefix "femto-" is derived from the Danish word "femten," meaning fifteen, and was adopted into the SI system to denote a factor of 10^-15.

Applications

Femtograms are commonly used in scientific disciplines that deal with very small quantities of material. For example:

• In biochemistry, femtograms are used to measure the mass of biomolecules such as proteins and nucleic acids.
• In pharmacology, the femtogram is used to quantify the amount of a drug in a given sample.
• In nanotechnology, femtograms are used to measure the mass of nanoparticles and other nanoscale materials.

Measurement Techniques

Measuring masses in femtograms requires highly sensitive instruments. Some of the techniques used include:

• Mass spectrometry, which can measure the mass of molecules with high precision.
• Atomic force microscopy, which can be used to measure the mass of individual atoms and molecules.
• Quartz crystal microbalance, which can detect minute changes in mass at the femtogram level.

Related Units

Other units of mass in the SI system include:

• Gram (g)
• Milligram (mg)
• Microgram (µg)
• Nanogram (ng)
• Picogram (pg)

See Also

• International System of Units
• Mass spectrometry
• Nanotechnology
• Biochemistry
• Pharmacology