The Types and Uses of Absorption Spectroscopy

In absorption spectroscopy, the quantity of energy absorbed by a sample is calculated as a function of the frequency or wavelength of the incident radiation. The absorption spectroscopy method determines a sample’s chemical composition because different substances absorb electromagnetic radiation at different frequencies. 

Researchers use Agilent absorption spectroscopy instruments to analyze molecules in chemistry, biology, food science, and pharmaceuticals to understand their structure and function. There are various kinds of absorption spectroscopy, and each of these methods detects various kinds of chemical bonds and functional groups by utilizing a distinct region of the electromagnetic spectrum.

Ultraviolet-Visible Spectroscopy

UV-visible (UV-vis) spectroscopy uses ultraviolet (UV) and visible light to evaluate the chemical makeup of a sample. Due to its sensitivity to molecular electronic transitions, UV-vis spectroscopy is a helpful tool for researching compounds with conjugated double-bond systems.

In UV-vis spectroscopy, a specimen is exposed to UV or visible light, and the radiation’s absorption is calculated as a function of the radiation’s wavelength or frequency. 

The wavelengths at which various chemical bonds and functional groups absorb visible light can be used to determine the kinds and numbers of molecules in a sample by looking at its absorption spectra.

UV-vis spectroscopy includes studying organic molecules, finding functional groups in unidentified substances, and determining specimen quality. Chemical, biological, materials, and pharmaceutical industries use UV-vis spectroscopy extensively. Using this analytical tool, scientists investigate the makeup and behavior of molecules in a sample.

Nuclear Magnetic Resonance Spectroscopy

Nuclear magnetic resonance (NMR) spectroscopy uses the magnetic characteristics of certain atomic nuclei when studying the structure and dynamics of molecules. NMR spectroscopy is based on the idea that some atomic nuclei, such as those of hydrogen, carbon, and nitrogen, have magnetic moments and can align with or against an external magnetic field.

NMR spectroscopy involves exposing a sample to radiofrequency (RF) pulses while held in a powerful magnetic field. As a function of the frequency of the incident radiation, the sample nuclei are assessed for their RF radiation absorption.

NMR spectroscopy is a potent analytical method that enables researchers to examine molecules’ dynamics, relationships, and structure in a sample. NMR spectroscopy has various uses, including examining organic compounds, finding functional groups in unidentified substances, and determining the purity of a sampling. 

Infrared Spectroscopy

Infrared (IR) spectroscopy analyzes the molecular structure of a material using infrared radiation. Infrared radiation is electromagnetic radiation with wavelengths longer than visible light but shorter than microwaves. IR spectroscopy electromagnetic spectrum range is between 750 nanometers and one millimeter.

In IR spectroscopy, a sample is exposed to infrared radiation, and the absorption of the radiation is measured to determine the wavelength or frequency of the incident radiation. 

The absorption spectrum of a specimen can be used to determine the kinds and numbers of molecules present in the sampling because different kinds of chemical bonds and functional groups absorb infrared radiation at particular wavelengths.

IR spectroscopy is an effective analytical method that enables researchers to examine the composition and behavior of molecules in a sampling. The use of IR spectroscopy allows the identification of functional groups in unknown compounds, analyzing organic molecules, and measuring a material’s purity.

The Uses of Absorption Spectroscopy

Absorption spectroscopy is one of the most frequently used technologies to determine the levels of absorbing species in solutions. Biochemists, biologists, and increasingly systems biologists employ this nondestructive method to measure the characteristics of functioning molecules and the constituent parts of cells.

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