What laboratory instrument measures light transmitted through a sample relative to wavelength?

The spectrophotometer is the laboratory instrument that measures light transmitted through a sample relative to wavelength. This device operates on the principle of light absorption and transmission, allowing researchers to determine the concentration of a specific substance in a solution by measuring how much light is absorbed at a particular wavelength.

In various scientific fields, including biochemistry and molecular biology, spectrophotometers are essential for quantifying nucleic acids, proteins, and other biomolecules. When light passes through a sample, some wavelengths are absorbed, while others are transmitted. By analyzing the amount of light transmitted, scientists can infer properties about the sample, such as concentration and purity.

Other instruments listed, like chromatographs and mass spectrometers, serve different purposes. Chromatographs are used for separating components within a mixture, while mass spectrometers analyze the mass of particles to identify and quantify them. An ultrasonicator, on the other hand, uses sound waves to agitate particles in a sample, primarily to facilitate mixing or disruption, but not to measure light or wavelength.