DETERMINATION OF BLOOD ETHANOL LEVELS: COMPARISON OF ENZYMATIC AND GAS CHROMATOGRAPHIC METHODS

Year 2012, Volume: 26 Issue: 3, 89 - 91, 30.12.2012

Nebile Dağlıoğlu Alper Keten Ramazan Akçan Pınar Efeoğlu Necmi Çekin

https://izlik.org/JA23MG27UZ

Abstract

Objective:
Forensic and clinical laboratories
determine blood alcohol concentrations (BAC) using gas chromatography–head space, and enzymatic ethanol assay methods.
However, the use of enzymatic
ethanol assays is still controversial. Several authors have reported that increased concentrations
of lactate dehydrogenase might
cause false-positive results with
enzymatic ethanol assays. This
study was designed to compare
the Roche® enzymatic method
with the reliable conventional
gas chromatographic method.
Methods:
The blood samples collected from
20 voluntary individuals (3 females and 17 males) were analyzed
by both methods. A control group
was constituted from 10 healthy
individuals that were non-users of
alcohol.
Results:
Blood LDH levels of all participants
were varying between 294-932
U/L. A significant correlation
related with the effect of LDH
level on BAC was not detected
since the LDH levels were in
normal range. The present study
shows significant quantitative
difference in detected blood
ethanol levels of the experimental
group between the enzymatic and
gas chromatographic methods.
All samples of alcohol users
were positive and the percentage
difference between BAC obtained
by the enzymatic versus the GCHS method ranged from -166
to +17%. Nineteen (95%) in 20
positive samples showed lower
detected ethanol values with the
enzymatic method compared
to GC-HS analysis. Despite the
fact that ethanol was found to
be negative in all samples of the
control group with GC-HS method,
enzymatic method gave false
positive results for two samples
(10%) of the control group.
Conclusion:
GC-HS still remains as a specific,
accurate and reliable method for
determination of ethanol levels.

Keywords

blood alcohol concentration , enzymatic ethanol assay , gas chromatography-head space

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