Terahertz gas-phase spectroscopy: chemometrics for security and medical applications

We describe a spectrometer consisting of a vector network analyzer, a gas absorption cell, and a quasi-optical bench that acquires terahertz spectra of gaseous substances and mixtures. We tested volatile organic compounds that are medical biomarkers or chemicals which can be found on the US Environm...

Full description

Saved in:
Bibliographic Details
Published in:Analyst (London) 2015-01, Vol.14 (1), p.213-222
Main Authors: Neumaier, P. F.-X, Schmalz, K, Borngräber, J, Wylde, R, Hübers, H.-W
Format: Article
Language:English
Subjects:
Algorithms
Biomarkers - analysis
Chemometrics
Environment protection
Gases - chemistry
Least-Squares Analysis
Lists
Medical
Organic Chemicals - analysis
Principal Component Analysis
Regression
Spectrometers
Terahertz Spectroscopy
Citations: Items that this one cites
Items that cite this one
Online Access:Get full text
Tags: Add Tag
No Tags, Be the first to tag this record!
Description
Summary:We describe a spectrometer consisting of a vector network analyzer, a gas absorption cell, and a quasi-optical bench that acquires terahertz spectra of gaseous substances and mixtures. We tested volatile organic compounds that are medical biomarkers or chemicals which can be found on the US Environment Protection Agency list of harmful substances. Absorption spectra at gas pressures between 10 Pa and 5000 Pa were recorded. A subsequent multivariate data analysis demonstrated excellent qualitative and quantitative identification of pure substances and complex mixtures. The applied multivariate algorithms are principal components analysis, partial least square regression and soft independent modelling of class analogy. A THz-spectrometer based on a VNA, an absorption cell and PCA-/PLS-/SIMCA-analysis demonstrates a VOC-gas-mixture identification with 2% accuracy.
ISSN:0003-2654
1364-5528
DOI:10.1039/c4an01570c