breath analysis by cavity ring down spectroscopy joseph guss department of physical chemistry...
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Breath Analysis by Cavity Ring Down Spectroscopy
Joseph GussDepartment of Physical ChemistryUniversity of Helsinki
Diagnosis
Cavity ring down spectroscopy
Breath transferred to cell
Patient
Diseases
Overall Schematic
Biomarkers
Lab photo
Scanning range
6350 – 6575 cm-1
1520 – 1575 nm
Sensitivity 5 10-10 cm-1Hz-1/2
Breath Spectrum
K. Stamyr, O. Vaittinen, J. Jaakola, J. Guss, M. Metsälä, G. Johanson, and L. Halonen, Biomarkers, in press as of April 2009.
Breath gas Formula Average fraction
methane CH4 2-10carbon monoxide CO 1-10
acetone (CH3)2CO 0-1
ammonia NH3 50-800
isoprene C5H8 50-200nitric oxide NO 10-50
nitrous oxide NO2 1-20
ethane C2H6 0-10
pentane C5H12 0-10carbonyl sulfide OCS 0-10
Endogenous trace gases in breath
ppm
ppb
Diseases
Disease Biomarker
schizophrenia pentane, CS2 [1]
angina pectoris CO
hyperbilirubinemia CO [2]
diabetes (type 2) acetone
asthma NO
liver diseases OCS, NH3
lung cancer VOCs
Helicobacter pyloriinfection
CO2 (urea breath test)
Diseases and biomarkers in breath
1. Journal of Clinical Pathology (1994) September, 47(9), 870.2. Pediatrics International (2001) 43, 329–333
• Has been shown to cause stomach ulcers
• 2005 Nobel Prize in medicine: Warren and Marshall
Helicobacterpylori
© The Nobel Prize committee for Physiology
or Medicine
Possibility of direct measurement of ammonia
(NH2)2CO + H2O CO2 + 2NH3
urease
Helicobacter pylori
13C urea breath test
Ammonia in raw breath samples
-80 -55 -30 -5 20 45 70 95 120 145 1700
1
2
3
4
5N
um
ber
of
sam
ple
s
%[NH3]
Positive Negative
Change in ammonia concentration after ingestion of 13C urea
Thanks
€ Emil Aaltosen Säätiö
Helsinki» Dr Florian Schmidt» Dr Olavi Vaittinen» Janne Jaakola» Prof. Lauri Halonen» Markus Metsälä
Stockholm» Kristin Stamyr» Gunnar Johanson
Tampere» Tapani Ahola» Mika Kähönen» Terho Lehtimäki