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ID 115578
著者
Tanikami, Yuki Tokushima University
キーワード
L-Ascorbic acid
Acid dissociation constants
Capillary zone electrophoresis
資料タイプ
学術雑誌論文
抄録
Two-steps acid dissociation constants of L-ascorbic acid (AA) were determined through the changes in the effective electrophoretic mobility in capillary zone electrophoresis. Although ascorbic acid is oxidatively degradable in an aqueous solution, especially in alkaline conditions, the effective electrophoretic mobility of AA was successfully measured in the pH range between 1.87 and 11.97. In the analysis of the first-step acid dissociation constant (pKa1) at weakly acidic pH conditions, a coated capillary with 1,3-propanesultone and a pressure-assist were utilized to detect anionic AA. In the analysis of the second-step acid dissociation constant (pKa2) at weakly alkaline pH conditions, AA was successfully detected at the pH range up to 11.97 with the help of Cu catalyst to remove the dissolved oxygen in the separation buffer. Acid dissociation constants were independently determined as pKa1 = 4.15±0.01 and pKa2 = 12.07±0.04 by non-linear least-squares analyses. AA did not fully dissociate at the weakly alkaline pH range, and the effective electrophoretic mobility of the dianion form of AA was extrapolated for the analysis.
掲載誌名
Chromatography
ISSN
13483315
13428284
cat書誌ID
AA1137755X
出版者
The Society for Chromatographic Sciences
42
1
開始ページ
49
終了ページ
54
発行日
2021-01-27
EDB ID
出版社版DOI
出版社版URL
フルテキストファイル
言語
eng
著者版フラグ
著者版
部局
理工学系