Separation and Characterization of Soil HA Fluorescent and Non- fluorescent Fractions by Ultrafiltration in 7M Urea Followed by PAGE Coupled with Transilluminator Technique

摘要

It is well known that soil HAs are fluorescent compounds with fluorescence arising from many different fluorophores present in humic compounds. However, due to the chemical complexity and molecular size (MS) polydispersity of soil HA, the separation of soil HA in different fluorescent and non-fluorescent fractions have not yet been carried out. In this work we describe the results of soil HA separation on non-fluorescent and different fluorescence units using ultrafiltration (UF) in the presence of 7 M urea as a denaturating agent. All the UF fractions have been assayed by polyacrylamide gel electrophoresis (PAGE) coupled with transilluminator technique for rapid fluorescence detection. Using PAGE with detection in UV and white lights on transilluminator is a quite routine methodology for study of proteins and DNA. However, we are no aware of any literature data using this set-up in HS research. Further the H-NMR spectroscopy and thermochemolysis with subsequent identification of products by gas chromatography-mass spectrometry technique were used for the UF fluorescence and non-fluorescent fractions characterization.