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Article: Research findings from University of the Pacific update understanding of physical chemistry.
- Article from:
- Chemicals & Chemistry
- Article date:
- November 13, 2009
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According to a study from the United States, "The gas-phase acidities of four cysteine-polyalanine peptides, A(3,4)CSH and HSCA(3,4), were determined using the extended Cooks kinetic method with full entropy analysis. A triple-quadrupole mass spectrometer with an electrospray interface was employed for the experimental study."
"The ion activation was achieved via collision-induced dissociation (CID) experiments. The deprotonation enthalpies (Delta H-acid) of the peptides were determined to be 332.2 +/- 2.0 kcal/mol (A(3)CSH), 325.9 +/- 2.0 kcal/mol (A(4)CSH), 319.3 +/- 3.0 kcal/mol (HSCA(3)), and 319.2 +/- 4.0 kcal/mol (HSCA(4)). The deprotonation entropies ...