In FTIR spectroscopy, infrared radio waves (IR) are passed through a sample.

• The amount of IR that is absorbed (absorption) or passes through (transmission) by the molecules present is recorded and a spectrum generated
• All molecules have different absorption and transmission properties and these molecular signatures can be used to identify the compounds in a mixture

This technique allows high-throughput screening of biological samples.

• Ideally suited for metabolic fingerprinting applications e.g. for the rapid detection and diagnosis of diseases
• However, although this technique is highly reproducible, it's sensitivity and selectivity are not as high as other methods such as NMR or Mass Spectrometry based techniques