TY - JOUR
T1 - Applications of Hadamard transform to gas chromatography/mass spectrometry and liquid chromatography/mass spectrometry
AU - Lin, Cheng Huang
AU - Kaneta, Takashi
AU - Chen, Hung Ming
AU - Chen, Wen Xiong
AU - Chang, Hung Wei
AU - Liu, Ju Tsung
PY - 2008/8/1
Y1 - 2008/8/1
N2 - Successful application of the Hadamard transform (HT) technique to gas chromatography/mass spectrometry (GC/MS) and liquid chromatography/mass spectrometry (LC/MS) is described. Novel sample injection devices were developed to achieve multiple sample injections in both GC and LC instruments. Air pressure was controlled by an electromagnetic valve in GC, while a syringe pump and Tee connector were employed for the injection device in LC. Two well-known, abused drugs, 3,4-methylene-dioxy-N-methylamphetamine (MDMA) and N,N-dimethyltryptamine (DMT), were employed as model samples. Both of the injection devices permitted precise successive injections, resulting in clearly modulated chromatograms encoded by Hadamard matrices. After inverse Hadamard transformation of the encoded chromatogram, the signal-to-noise (S/N) ratios of the signals were substantially improved compared with those expected from theoretical values. The S/N ratios were enhanced ∼10-fold in HT-GC/MS and 6.8 in HT-LC/MS, using the matrices of 1023 and 511, respectively. The HT-GC/MS was successfully applied to the determination of MDMA in the urine sample of a suspect.
AB - Successful application of the Hadamard transform (HT) technique to gas chromatography/mass spectrometry (GC/MS) and liquid chromatography/mass spectrometry (LC/MS) is described. Novel sample injection devices were developed to achieve multiple sample injections in both GC and LC instruments. Air pressure was controlled by an electromagnetic valve in GC, while a syringe pump and Tee connector were employed for the injection device in LC. Two well-known, abused drugs, 3,4-methylene-dioxy-N-methylamphetamine (MDMA) and N,N-dimethyltryptamine (DMT), were employed as model samples. Both of the injection devices permitted precise successive injections, resulting in clearly modulated chromatograms encoded by Hadamard matrices. After inverse Hadamard transformation of the encoded chromatogram, the signal-to-noise (S/N) ratios of the signals were substantially improved compared with those expected from theoretical values. The S/N ratios were enhanced ∼10-fold in HT-GC/MS and 6.8 in HT-LC/MS, using the matrices of 1023 and 511, respectively. The HT-GC/MS was successfully applied to the determination of MDMA in the urine sample of a suspect.
UR - http://www.scopus.com/inward/record.url?scp=49449104168&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=49449104168&partnerID=8YFLogxK
U2 - 10.1021/ac800201r
DO - 10.1021/ac800201r
M3 - Article
AN - SCOPUS:49449104168
SN - 0003-2700
VL - 80
SP - 5755
EP - 5759
JO - Analytical Chemistry
JF - Analytical Chemistry
IS - 15
ER -