Biomedical Engineering Reference
In-Depth Information
Table 2
Oxidant
=
Antioxidant Biomarkers in Exhaled Breath Condensate and
Their Measurements
Values in EBC
Biomarker
Analysis
Non-smoker
Smoker
COPD
Reactive
oxygen
species
Hydrogen peroxide,
mM
Spectroscopy,
fluorometry,
chemiluminescence
0.01-0.09
0.10-0.75
0.2-2.6
Reactive
nitrogen
species
Nitrite, mM
Electrometry
0.64
0.44-2.4
2.6
Nitrite and nitrate, mM Spectroscopy
20.2
20.2-29.2
—
Nitrotyrosine, ng
=
mL
ELISA
0.66-6.3
7.2
—
Nitrosothiols, mM C
=
MS, HPLC
—
0.1-0.46
0.24
Lipid peroxidation
products
TBARS, mM
Colorimetry, ELISA
—
—
0.48
Malondialdehydes,
nmol
=
L
Enzyme
immunoassay
(EIA), GC
=
MS,
HPLC
17.2-19.4
nmol
=
Lby
LC
=
MS
—
57.2 by
LC
=
MS
F
2
-Isoprostanes,
pg
=
mL
Liquid
chromatography-
tandem mass
spectrometry
(LC
=
MS)
3.9-15.8 by
EIA and
7
4by
GC
=
MS
24.0
42.5
Antioxidant
Glutathione, nM
Spectrophotometry,
HPLC, liquid
chromatography-
tandem mass
spectrometry
——
14.1
H
2
O
2
in EBC is unknown but may in part derive from the release of O
2
-
from alveolar macrophages. Smokers and patients with COPD have higher
levels of exhaled H
2
O
2
than non-smokers, and levels are even higher during
exacerbations of COPD (25-27). However, H
2
O
2
levels vary considerably in
healthy young non-smokers and smokers from 0.01 to 0.09 mM and 0.10 to
0.75 mM, respectively (28). This variation (60-80%) in H
2
O
2
concentrations
may be attributed to different storage conditions and
=
or analytical techni-
ques used for EBC H
2
O
2
assay. Thus the variability of the measurement
of exhaled H
2
O
2
due to its highly volatile nature, along with the presence
of other confounding factors, e.g., increased generation of ROS by cigarette
