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Updated: Jun 28, 2026

Microdialysis of Ethanol During Operant Ethanol Self-administration and Ethanol Determination by Gas Chromatography
Published on: September 5, 2012
Determination of ethanol in liquor by near-infrared spectrophotometry with flow injection
P Tipparat1, S Lapanantnoppakhun, J Jakmunee
1Department of Chemistry, Faculty of Science, Chiang Mai University, Chiang Mai 50200, Thailand.
Abstract:
A simple procedure for the determination of ethanol in a liquor by near-infrared (NIR) spectrophotometry with flow injection (FI) is proposed. A liquor sample is equilibrated off-line with dried chloroform to extract ethanol into the organic phase. The extract is injected into a carrier stream of dried chloroform passing through a home-made flow through cell (1 mm path length) sitting in a NIR spectrophotometer for continuous monitoring of absorbance at 2305 or 2636 nm. The ethanol content can be evaluated from a calibration established by a plot of change in absorbance versus concentration of ethanol standard solutions. Optimization of the system will be discussed. A calibration is linear in the range of 20-50% (v/v) ethanol. A throughput of 240 injections h(-1) can be obtained. The procedure is validated by comparing the results with an analysis using gas chromatography.
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