Mass Spec Sensitivity to 480 Molecules Reported

For some time, the sensitivity of Mass Spectrometry has been represented by a lower detection limit in the region of tens of thousands of molecules. Now, a recent report of a soft ionization method developed by Gary Siuzdak and co-workers at Scripps Research Institute allows the extension of detection capability to a limit of 500 molecules or less. A series of dilution experiments involving a peptide (des-Arg⁹-bradykinin) commonly used as a sensitivity standard demonstrated a lower detection limit of 800x10^-24 moles. The technique appears to allow extraction of minute amounts of analyte from complex matrices containing salts and other contaminants that can compromise Mass Spec analysis [Anal. Chem., 76, 4484 (2004)].