Formation of (M-H)+ Ions under Fast Atom Bombardment Conditions: Trolox and .ALPHA.-Tocopherol.

Fast - atom - bombardment mass spectrometry

A detailed study of the mass spectra of peptides produced by the new technique of fast-atom bombardment is reported. Molecular weights of unmodified peptides containing up to 21 amino acids have been determined. In favourable cases, the molecular-weight determination may be made on as little as 0.1 nmol of sample. Positive-ion and negative-ion spectra are obtained with equal facility. With samp...

Fast Atom Bombardment (FAB)-MS

FAST ATOM BOMBARDMENT MASS SPECTROMETRY (FABMS) ANALYSIS OF AN N- TERMINAL - BLOCKED PEPTIDE

FABMS analysis of T-lb peptide before and after one cycle of Edman degradation indicated an unblocked N-terminal Thr residue for this tryptic peptide. In contrast , our data showed a molecular protonated ion, MH + for T- la peptide at 655 mass units (mu) which is 42 mu higher than the MH ion of T- 1b peptide. In addition, T- la peptide was not amenable to one cycle of manual Edman degrada...

Continuous-flow fast atom bombardment mass spectrometry.

The continuous-flow fast atom bombardment probe performs equally well with or without a high-performance liquid chromatography column producing clean spectra containing little or no background noise. Its function as a liquid chromatography-mass spectrometry interface for labile and involatile samples has been illustrated with reference to dansylated amino acids. The versatility of the new probe...

Fast atom bombardment-induced condensation of glycerol with ammonium surfactants. I: Regioselectivity of the adduct formation.

Fast atom bombardment promotes condensation between trimethyl tetradecyl ammonium cations and the glycerol matrix. Bond formation at both the head and tail of the surfactant is demonstrated by low energy collision-induced dissociation (ClD) of deuterium-labeled precursors, with a preponderance of the reaction apparently occurring at the tail. Two distinct ClD pathways are identified for each ki...