| abstract |
A novel electrospray interface provides high sensitivity and signal stability for mass spectrometric detection of analytes in solvents with high water content including 100% water. The electrospray capillary tip section is heated close to the boiling point of the solvent. An approximately 20 DEG C. hotter airstream is also used. Its flow is coaxial and codirectional to the electrospray. With this arrangement, the analyte signal sensitivity and stability obtained with neat water is equal to that with neat methanol. The charged state (degree of protonation) of protonated peptides sprayed from neat water and the heated spray is essentially identical to that observed with unheated spray where the solvent was 80% methanol-20% water. |