Real-time Monitoring technology of Mass spectrometry Speaker

Real-time Monitoring technology
of Mass spectrometry
Speaker : Achong

Outline
IMS
PTR-MS
SIFT-MS
Application of IMS
IMS-TOF
IMS-IMS-TOF
Application of PTR-MS
PIT-MS

Real-time Monitoring Mass spectrometry
Environmental science
Biochemical and medical diagnosis
Workplace safety
Security check

EI source
Analysis of atmospheric air is especially
challenging using electron ionization mass
spectrometry, because the gas loading of the
ion source by N2 and O2 (as well as water
vapor) can be excessive.
70 ev

Real-time Monitoring MS
Soft chemical ionization

Measurement in Real-Time
Without pre-concentration system

I. IMS (ion mobility spectrometer)
Ion mobility mass spectrometry (Eiceman,1991; Baumbach, 2001)
Analytical Chemistry, A390-A397, November 1, 2004

Ion mobility (K)
Journal of Bimolecular Technique, Vol.13, Issue 2, June, 2002

Ion Mobility-Mass Spectroscopy
Witt & Bowers: JACS. 2000, 122, 3458.

Ion mobility mass spectrometry
Advantages:
Multiform ion source could be applied.
Some isomer could be separated.
Real-time measurement
Disadvantages:
Lower mass resolution
Lower sensitivity to allow accurate analysis of
complex mixtures.
Standard is requisite

II. PTR-MS (proton-transfer reaction)
Proton-transfer reaction-mass spectrometry (Lagg A,
Taucher J, Hansel A, Lindinger W. 1994.)
/>
proton-transfer reaction
H

3
O
+
+ R → RH
+
+ H
2
0
[RH
+
]
= [H
3
O
+
]
o
(1 - e
-k[R]t
)
= [H
3
0
+
]
o
[R]kt
J. Mass Spectrom Ion Processes, 173 (1998) 191-241

J. Mass Spectrom Ion Processes, 173 (1998) 191-241

J. Mass Spectrom Ion Processes, 173 (1998) 191-241

PTR mass spectrometry
Advantages:
Soft ionization and low matrix effect
Real-time measurement
Low limit of detection (0.5 ppbv for 1-min measurements)
Disadvantages:
A large number of VOCs could not be identified and
quantified.

III. SIFT-MS (selected ion flow tube)
/>Adams NG, Smith D. 1976.
Spanel P ,Smith D. 1995.


SIFT mass spectrometry
Advantages:
application of multiple reagent ions (H3O
+
, NO
+
and O2
+
)
quantification in real-time
discriminate isomers in Real-Time
Disadvantages:
The kinetic parameters of the reagent ion and the analyte

ion must be known.
Selected ion flow tube mass spectrometry for no-line trace gas analysis
David Smith and Patrik Spanel
Reference : Mass Spectrometry Reviews, 2005, 24, 661– 700

Application of IMS
IMS/TOF
IMS/IMS/TOF

Ion Mobility/TOFMS
Anal. Chem. 2003, 75,6202-6208

Pulse sequence of IMS & TOF
Anal. Chem. 2003, 75,6202-6208

example spectrum
Analytical Chemistry, 1998 Vol. 70, No. 11, June 1,

Anal. Chem. 2003, 75,6202-6208

collision-induced dissociation
/>
IMS/IMS/TOF
Anal. Chem. 2006, 78,4161-4174

operational mode A
Anal. Chem. 2006, 78,4161-4174