國立高雄大學圖資館 |

登入

回首頁

Characterization of humic substances using high-performance size exclusion chromatography and on-the-fly fluorescence lifetime detection in capillary gel electrophoresis

紀錄類型:	書目-電子資源 : Monograph/item
正題名/作者:	Characterization of humic substances using high-performance size exclusion chromatography and on-the-fly fluorescence lifetime detection in capillary gel electrophoresis
作者:	Blomberg, Jessica Andrea LoDuca.
面頁冊數:	139 p.
附註:	Source: Dissertation Abstracts International, Volume: 65-04, Section: B, page: 1833.
附註:	Supervisor: Linda B. McGown.
Contained By:	Dissertation Abstracts International65-04B.
標題:	Chemistry, Analytical.
電子資源:	http://pqdd.sinica.edu.tw/twdaoapp/servlet/advanced?query=3129062
ISBN:	0496763229

Characterization of humic substances using high-performance size exclusion chromatography and on-the-fly fluorescence lifetime detection in capillary gel electrophoresis
Blomberg, Jessica Andrea LoDuca.

Characterization of humic substances using high-performance size exclusion chromatography and on-the-fly fluorescence lifetime detection in capillary gel electrophoresis [electronic resource] - 139 p.

Source: Dissertation Abstracts International, Volume: 65-04, Section: B, page: 1833.

Thesis (Ph.D.)--Duke University, 2003.

Humic substances (HS) are polyelectrolytic macromolecules derived from organic components in soil and water. The critical roles HS play in the environment make it necessary to improve their characterization, which is complicated by their inherently heterogeneous nature and polyfunctionality. A robust characterization method requires sensitivity to minor differences in structural composition between samples. The goal of this dissertation research is to investigate the use of chromatographic and electrophoretic techniques with absorption and fluorescence detection to provide a detailed profile of HS as a function of size.

ISBN: 0496763229Subjects--Topical Terms:

224793
Chemistry, Analytical.

Characterization of humic substances using high-performance size exclusion chromatography and on-the-fly fluorescence lifetime detection in capillary gel electrophoresis
LDR:03525nmm _2200301 _450 001 162658
005 20051017073509.5
008 230606s2003 eng d
020 $a 0496763229
035 $a 00149159
035 $a 162658
040 $a UnM $c UnM
100 0 $a Blomberg, Jessica Andrea LoDuca. $3 227802
245 1 0 $a Characterization of humic substances using high-performance size exclusion chromatography and on-the-fly fluorescence lifetime detection in capillary gel electrophoresis $h [electronic resource]
300 $a 139 p.
500 $a Source: Dissertation Abstracts International, Volume: 65-04, Section: B, page: 1833.
500 $a Supervisor: Linda B. McGown.
502 $a Thesis (Ph.D.)--Duke University, 2003.
520 # $a Humic substances (HS) are polyelectrolytic macromolecules derived from organic components in soil and water. The critical roles HS play in the environment make it necessary to improve their characterization, which is complicated by their inherently heterogeneous nature and polyfunctionality. A robust characterization method requires sensitivity to minor differences in structural composition between samples. The goal of this dissertation research is to investigate the use of chromatographic and electrophoretic techniques with absorption and fluorescence detection to provide a detailed profile of HS as a function of size.
520 # $a The first project utilizes a high-performance size exclusion (HPSEC) column, G3000PW TSKgel, to characterize by MW using poly (styrene sulfonates) as calibration size standards. The goal was to establish MW values for several IHSS HS. Separation of HS using the TSKgel column generated MW values, ranging from 2,500--10,000 Da, which are in the range reported in the literature (800--20,000 Da). Structural subunits of HS, primarily aromatic and aliphatic carboxyl, hydroxyl and phenolic groups, were tested to determine the possible role of secondary interactions, including adsorption and ion exclusion, which may affect separation. The calculated MW values for the structural subunits indicated that both secondary interactions must be considered when evaluating MWs obtained with the TSKgel column.
520 # $a The second project utilized the charged nature and intrinsic fluorescence of HS for characterization by capillary gel electrophoresis with on-the-fly fluorescence lifetime detection (CGE-OFLD). Recent studies in our group found that HS exhibits 2--3 lifetime components across the broad, humic hump in capillary zone electrophoresis (CZE). To complement these findings, this project added a poly (ethylene glycol) gel to the mobile phase and used a poly (vinyl alcohol) coated capillary, in order to decrease the mobilities of the HS and add a sieving mechanism to separation achieved with CZE. The results showed that fluorescence lifetime decreases with increasing size of the HS molecule. In addition, all HS exhibited a bi-exponential decay across the humic peak. Lifetime-resolved electropherograms of the lifetime components varied according to source (soil, peat, and aquatic). This suggests that OFLD is sensitive to the MW distribution of HS in the CGE experiment.
590 $a School code: 0066.
650 # 0 $a Chemistry, Analytical. $3 224793
650 # 0 $a Environmental Sciences. $3 212393
690 $a 0486
690 $a 0768
710 0 # $a Duke University. $3 226880
773 0 # $g 65-04B. $t Dissertation Abstracts International
790 $a 0066
790 1 0 $a McGown, Linda B., $e advisor
791 $a Ph.D.
792 $a 2003
856 4 0 $u http://libsw.nuk.edu.tw/login?url=http://pqdd.sinica.edu.tw/twdaoapp/servlet/advanced?query=3129062 $z http://pqdd.sinica.edu.tw/twdaoapp/servlet/advanced?query=3129062