Measurement of acetaldehyde in exhaled breath using a laser absorption spectrometer.
A high-resolution liquid-nitrogen-free mid-infrared tunable diode laser absorption spectroscopy (TDLAS) system was used to perform real-time measurement of acetaldehyde concentrations in human exhaled breath following ingestion of an alcoholic beverage. Acetaldehyde absorption features were measured near 5.79 mum (1727 cm(-1)) using a IV-VI semiconductor laser, a 100 m long path optical gas cell, and second- harmonic detection coupled with wavelength modulation. Acetaldehyde levels were measured with a minimum detection limit of 80 ppb for 5 s integration time. The variations in exhaled acetaldehyde levels over time were analyzed prior to and following ingestion of two different amounts of white wine. A method to calibrate acetaldehyde measurements internally using water vapor absorption lines was investigated to eliminate the need for system calibration with gas standards. The potential of a TDLAS system to be used as a noninvasive clinical tool for measurements of large volatile compounds with possible applications in cancer detection is demonstrated.
Kamat
Pratyuma C
PC
Ekips Technologies, Incorporated, Norman, Oklahoma 73069, USA.
Roller
Chad B
CB
Namjou
Khosrow
K
Jeffers
James D
JD
Faramarzalian
Ali
A
Salas
Rodolfo
R
McCann
Patrick J
PJ
D000042:Absorption; D000079:Acetaldehyde / Q000032:analysis* / Q000737:chemistry; D001944:Breath Tests; D002138:Calibration; D005740:Gases; D006801:Humans; D007834:Lasers; D008962:Models, Theoretical; D055095:Optics and Photonics; D013053:Spectrophotometry; D013055:Spectrophotometry, Infrared; D013997:Time Factors; D014867:Water / Q000737:chemistry
D005740:Gases; D014867:Water; D000079:Acetaldehyde