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LAAN-A-GC-E051

Application Gas Chromatography

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Analysis of Carbon Monoxide in Blood
No. G286

Carbon monoxide (CO) is known as a toxic gas
produced from the incomplete combustion of organic 9-mL vial
compounds. Since CO is responsible for many cases of
poisoning, the carboxyhemoglobin saturation level is
measured to be used as an index to determine whether 0.25 mL of blood sample
poisoning by carbon monoxide has occurred. Gas
chromatography thermal conductivity detectors (GC- 0.5 mL of water
TCD) employ an indirect measurement method that 0.25 mL of oxidizing agent *
isolates carbon monoxide in blood for analysis, but
sensitivity is not very high. On the other hand, barrier
discharge ionization detectors (BID) are able to detect
Heated to 30 °C for 90 minutes
most compounds, with the exception of helium and
neon, at high sensitivity compared to TCD. BID analysis
is useful because measuring at higher sensitivities
allows the volume of a blood sample used in testing to
be reduced, enabling any remaining blood in the Injection of 0.1 mL of gas into the GC using a gas-tight syringe
sample to be used in other tests. This article introduces * Oxidizing agent composition: Aqueous solution comprising
an example of measuring carbon monoxide in blood 20 % K3[Fe(CN)6] and 5 % saponin
using GC-BID.
S. Uchiyama
Example of Sample Pretreatment

„ Analysis Method
The pretreatment method was performed as follows by „ Measurement of Blood Sample Saturated with
referencing "Quantitative Testing 1-2 (2)" under "II-1 Carbon Monoxide
Toxic Gas Testing Methods" in "Testing Methods and A blood sample saturated with carbon monoxide was
Annotation for Toxic Pharmaceuticals 2006". created by bubbling 10 mL of CO through a 25 mL
1. Preparation of potassium ferricyanide aqueous blood sample and mixing, and this process was
solution (oxidizing agent) repeated nine times. An untreated blood sample and
20 g of potassium ferricyanide and 5 g of saponin the blood sample saturated with carbon monoxide
were dissolved in distilled water to precisely obtain were analyzed according to steps 2 and 3 of the
a volume of 100 mL. analysis method and the resulting chromatograms are
shown in Fig. 2.
2. Preparation of sample solution
0.25 mL of blood sample, 0.5 mL of distilled water,
and 0.25 mL of oxidizing agent were added to a
9-mL vial and the vial was sealed immediately. CO
3. Measurement
The blood sample was kept warm at 30 °C for
90 minutes and then measurement was performed
by injecting 0.1 mL of headspace gas into the GC
using a gas-tight syringe. The Rt-Msieve 5A column
was used.
Blood sample saturated
with carbon monoxide
Table 1 Analysis Conditions
Model : Tracera (GC-2010 Plus + BID-2010 Plus)
Column : RESTEK Rt-Msieve 5A Untreated blood sample
(30 m × 0.53 mm I.D., df = 50 μm)
with Particle Trap 2.5 m
Column Temp. : 100 °C
Inj. Mode : Split 1:7 1.75 2.00 2.25 2.50 2.75 3.00 3.25 3.50 min
Inj.Temp : 250 °C
Carrier Gas : He 45 cm/sec (constant linear velocity mode)
Det. Temp. : 280 °C Comparison of Untreated Blood Sample and Blood
Discharge Gas : 50 mL/min (He) Sample Saturated with Carbon Monoxide
Inj. Volume : 0.1 mL