JMSSJ On-line, Vol. 52 (2004) No. 1, pp. 29-32
Molecular Weight Characterization of Humic Substances by MALDI-TOF-MS
>> Full Text PDF
>> References
    Toshiyuki SHINOZUKA,*a) Mitsuhiro SHIBATA,a) and Tatsuaki YAMAGUCHIa)

    *a) Corresponding author. Tel.: +81-47-478-0420; fax: +81-47-478-0439 E-mail address: cityamag@pf.it-chiba.ac.jp Department of Life and Environmental Sciences, Chiba Institute of Technology (2-17-1 Tsudanuma, Narashino, Chiba 275-0016, Japan)
This study involved the use of matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF-MS) to determine the molecular weight distribution of the humic substances, humic acid (HA), and fulvic acid (FA), extracted from peat and soil. The results of MALDI-TOF-MS were compared with the conventional method of high performance size exclusion chromatography (HPSEC) for determining the molecular size distribution of the humic substances. The number-average molecular weight (Mn) of peat-based HA, peat-based FA, soil-based HA, and soil-based FA evaluated by MALDI-TOF-MS were 3,700, 2,900, 10,500, and 9,700, respectively. These results indicate that FA has a lower molecular weight than HA in samples of the same origin, and peat-based HA and FA have considerably lower molecular weights than soil-based HA and FA.
Key words: Humic substance, Humic acid, Fulvic acid, Molecular weight, MALDI-TOF-MS, HPSEC
[ Full Text PDF ]    [ References ]
© COPYRIGHT by The Mass Spectrometry Society of Japan. All Rights Reserved.