Spectrophotometry

Spectrophotometry is a quantitative method used in chemistry and physics to measure the absorption of a substance at different wavelengths of light. It is a key technique in the fields of biochemistry and molecular biology.

History

The concept of spectrophotometry dates back to the 19th century, when scientists began studying the absorption and emission of light by matter. The first practical spectrophotometer was developed in the early 20th century by Arnold Beckman.

Principles

Spectrophotometry is based on the principle that every substance absorbs or transmits light over a certain range of wavelength. This property is known as the absorption spectrum. The amount of light absorbed or transmitted is measured by a spectrophotometer, which produces a graph of the absorption spectrum.

Types

There are several types of spectrophotometry, including UV/Vis spectrophotometry, infrared spectrophotometry, and atomic absorption spectrophotometry. Each type uses a different range of the electromagnetic spectrum and is suited to different types of analysis.

Applications

Spectrophotometry is used in many scientific fields, including chemistry, biochemistry, molecular biology, and environmental science. It is used to measure the concentration of a substance in a solution, to study the chemical kinetics of reactions, and to identify substances by their absorption spectra.

See also

• Colorimetry
• Spectroscopy
• Absorption spectroscopy
• Fluorescence spectroscopy