The 19F NMR spectra are an analytical technique used to identify fluorine-containing compounds. 19F is 100% naturally abundant and with a spin quantum number of 1/2. It has the highest NMR sensitivity of the naturally occurring nuclides except for 1H. In addition, 19F NMR spectra have wide chemical shift dispersion and lack of background. Thus 19F NMR spectra are widely used in a large number of publications and reviews. This is one of the most important nuclei for NMR spectroscopy due to analysis of many biopharmaceutical products containing C-F bonds. The 19F NMR also can be used to verify the removal of trifluoroacetic acid (TFA) in the final products of synthetic peptides.
Inherent sensitivity of the chemical shift to the local environment of fluorine may contribute a lot to 19F NMR spectra. The position of a 19F resonance correlates well with burial in proteins. What’s more, even slight differences in the dielectric properties of H2O and D2O manifest as different 19F chemical shifts for water exposed 19F probes. Both fluoroaliphatic and fluoroaromatic probes provide the large range of chemical shift in proteins. Generally the range of chemical shift of 19F is about 100 times larger than 1H, providing a sensitive method for conformational change without combined with 2D NMR. This unique characteristic is also useful in the dynamics analysis because the great extent of frequencies makes it easier to monitor the weak change.
Figure 19F-nuclear magnetic resonance (NMR) spectra [1]
Creative Proteomics with its scientists are experienced in 19F NMR and can provide professional services for structural information of proteins, peptides and metabolites of biological pharmaceuticals, as well as other related analysis service.
[1] Conformational and thermodynamic properties modulate the nucleotide excision repair of 2-aminofluorene and 2-acetylaminofluorene dG adducts in the NarI sequence. Jain V, Nucleic Acids Res., 2012, 40(9).
