High sensitivity Fourier transform ion cyclotron resonance mass spectrometry for biological analysis with nano-LC and microelectrospray ionization.
Modifications to a 7 T nano-LC micro-ESI FT-ICR mass spectrometer, including a shorter octopole, approximately 100% duty cycle, improved nano-LC micro-ESI emitter tips, and reverse-phase HPLC resins that require no ion-pairing agent, combine to achieve attomole detection limit. Three peptides in a mixture totaling 500 attomoles (amol) each in water (10 microL, 50 amol/microL) are separated and detected, demonstrating detection from a mixture at low endogenous biological concentration. Two peptides in a mixture totaling 500 amol each in artificial cerebrospinal fluid (1 microL, 500 amol/microL) are separated and detected, demonstrating detection from a mixture at a biological concentration in a biological solvent. The highest sensitivity is attained with arg8-vasotocin, in which a total of 300 amol is detected in artificial cerebrospinal fluid (1 microL, 300 amol/microL) and a total of 100 amol in water (1 microL, 100 amol/microL). Arg8-vasotocin isolated from the pineal gland of rainbow trout is detected, demonstrating the ability of FT-ICR to detect and identify a true endogenous biological analyte.
Quenzer
T L
TL
National High Magnetic Field Laboratory, Florida State University, 1800 East Paul Dirac Drive, Tallahassee, Florida 32310, USA.
Emmett
M R
MR
Hendrickson
C L
CL
Kelly
P H
PH
Marshall
A G
AG
D000818:Animals; D002851:Chromatography, High Pressure Liquid; D017357:Cyclotrons; D019075:Electrophoresis, Capillary; D005583:Fourier Analysis; D009682:Magnetic Resonance Spectroscopy; D010455:Peptides / Q000032:analysis*; D010902:Pituitary Gland / Q000737:chemistry; D021241:Spectrometry, Mass, Electrospray Ionization; D014337:Trout
D010455:Peptides