東華大學圖書館 |

Language: English

Help

回圖書館首頁

手機版館藏查詢

Back to Search results for [ null ]

Switch To: Labeled | MARC Mode | ISBD

Synthesis of isotope-labelled methox...

Chen, Xiaonan.

Linked to FindBook

Google Book

Amazon

博客來

Synthesis of isotope-labelled methoxypyrazine compounds as internal standards, and, Quantitative determination of aroma methoxypyrazines in water and wines by solid-phase extraction with isotope dilution-GC-MS.

Record Type:	Electronic resources : Monograph/item
Title/Author:	Synthesis of isotope-labelled methoxypyrazine compounds as internal standards, and, Quantitative determination of aroma methoxypyrazines in water and wines by solid-phase extraction with isotope dilution-GC-MS./
Author:	Chen, Xiaonan.
Description:	77 p.
Notes:	Source: Masters Abstracts International, Volume: 44-04, page: 1837.
Contained By:	Masters Abstracts International44-04.
Subject:	Chemistry, Analytical. -
Online resource:	http://pqdd.sinica.edu.tw/twdaoapp/servlet/advanced?query=MR10708
ISBN:	9780494107089

Synthesis of isotope-labelled methoxypyrazine compounds as internal standards, and, Quantitative determination of aroma methoxypyrazines in water and wines by solid-phase extraction with isotope dilution-GC-MS.
Chen, Xiaonan.

Synthesis of isotope-labelled methoxypyrazine compounds as internal standards, and, Quantitative determination of aroma methoxypyrazines in water and wines by solid-phase extraction with isotope dilution-GC-MS. - 77 p.

Source: Masters Abstracts International, Volume: 44-04, page: 1837.

Thesis (M.Sc.)--Brock University (Canada), 2005.

An efficient way of synthesizing the deuterium labelled analogues of three methoxypyrazine compounds: 2-d3-methoxy-3-isopropylpyrazine, 2-d3-methoxy-3-isobutylpyrazine, and 2-d3-methoxy-3-secbutylpyrazine, has been developed. To confirm that the deuterium labels had been incorporated into the expected positions in the molecules synthesized, the relevant characterization by NMR, HRMS and GC/MS analysis was conducted. Another part of this work involved quantitative determination of methoxypyrazines in water and wines. Solid-phase extraction (SPE) proved to be a suitable means for the sample separation and concentration prior to GC/MS analysis. Such factors as the presence of ethanol, salt, and acid have been investigated which can influence the recovery by SPE for the pyrazines from the water matrix. Significantly, in this work comparatively simple fractional distillation was attempted to replace the conventional steam distillation for pre-concentrating a sample with a relatively large volume prior to SPE. Finally, a real wine sample spiked with the relevant isotope-labelled methoxypyrazines was quantitatively analyzed, revealing that the wine with 10 beetles per litre contained 138 ppt of 2-methoxy-3-isopropylpyrazine. Interestingly, we have also found that 2-methoxy-3-secbutylpyrazine exhibits an extremely low detection limit in GC/MS analysis compared with the detection limit of the other two methoxypyrazines: 2-methoxy-3-isopropylpyrazine and 2-methoxy-3-isobutylpyrazine.

ISBN: 9780494107089Subjects--Topical Terms:

586156
Chemistry, Analytical.

Synthesis of isotope-labelled methoxypyrazine compounds as internal standards, and, Quantitative determination of aroma methoxypyrazines in water and wines by solid-phase extraction with isotope dilution-GC-MS.
LDR:02414nmm 2200253 4500 001 1830185
005 20070423122859.5
008 130610s2005 eng d
020 $a 9780494107089
035 $a (UnM)AAIMR10708
035 $a AAIMR10708
040 $a UnM $c UnM
100 1 $a Chen, Xiaonan. $3 1030501
245 1 0 $a Synthesis of isotope-labelled methoxypyrazine compounds as internal standards, and, Quantitative determination of aroma methoxypyrazines in water and wines by solid-phase extraction with isotope dilution-GC-MS.
300 $a 77 p.
500 $a Source: Masters Abstracts International, Volume: 44-04, page: 1837.
502 $a Thesis (M.Sc.)--Brock University (Canada), 2005.
520 $a An efficient way of synthesizing the deuterium labelled analogues of three methoxypyrazine compounds: 2-d3-methoxy-3-isopropylpyrazine, 2-d3-methoxy-3-isobutylpyrazine, and 2-d3-methoxy-3-secbutylpyrazine, has been developed. To confirm that the deuterium labels had been incorporated into the expected positions in the molecules synthesized, the relevant characterization by NMR, HRMS and GC/MS analysis was conducted. Another part of this work involved quantitative determination of methoxypyrazines in water and wines. Solid-phase extraction (SPE) proved to be a suitable means for the sample separation and concentration prior to GC/MS analysis. Such factors as the presence of ethanol, salt, and acid have been investigated which can influence the recovery by SPE for the pyrazines from the water matrix. Significantly, in this work comparatively simple fractional distillation was attempted to replace the conventional steam distillation for pre-concentrating a sample with a relatively large volume prior to SPE. Finally, a real wine sample spiked with the relevant isotope-labelled methoxypyrazines was quantitatively analyzed, revealing that the wine with 10 beetles per litre contained 138 ppt of 2-methoxy-3-isopropylpyrazine. Interestingly, we have also found that 2-methoxy-3-secbutylpyrazine exhibits an extremely low detection limit in GC/MS analysis compared with the detection limit of the other two methoxypyrazines: 2-methoxy-3-isopropylpyrazine and 2-methoxy-3-isobutylpyrazine.
590 $a School code: 1476.
650 4 $a Chemistry, Analytical. $3 586156
650 4 $a Chemistry, Agricultural. $3 1021829
690 $a 0486
690 $a 0749
710 2 0 $a Brock University (Canada). $3 1018667
773 0 $t Masters Abstracts International $g 44-04.
790 $a 1476
791 $a M.Sc.
792 $a 2005
856 4 0 $u http://pqdd.sinica.edu.tw/twdaoapp/servlet/advanced?query=MR10708