Fluorescent labeling affected the structural/conformational properties of arabinoxylans

Carbohydr Polym. 2021 Aug 1:265:118064. doi: 10.1016/j.carbpol.2021.118064. Epub 2021 Apr 17.

Abstract

Three fluorescent-labeling methods, including DMSO/DBTD, reductive amination and fluoresceinamine (FA), were applied to label arabinoxylan (AX). The conjugates were named AF, ATF and ACF, respectively. Compared to AX, the water solubility of AF significantly decreased while that of ATF significantly increased (p < 0.05); both showed decreased solubility with increasing degree of substitution (DS). However, AX was not successfully labeled by the FA method due to poor solubility. The structural and conformational properties of the AF and ATF conjugates under different DS were compared. Results showed that fluorochrome (FITC) was successfully grafted onto AX molecule by using the DMSO/DBTD and reductive amination methods. A slight increased Mw was noticed for both AF and ATF. AF existed in a more compact conformation, while the chain conformation of ATF was more elongated at a lower DS (1.15 %) and more compact at a higher DS (1.34 %).

Keywords: Arabinoxylan; Conformation; Fluorescent labeling; Solubility; Structure.

MeSH terms

  • Carbohydrate Conformation
  • Dimethyl Sulfoxide / chemistry
  • Fluorescent Dyes / chemistry*
  • Molecular Structure
  • Organotin Compounds / chemistry
  • Solubility
  • Spectrometry, Fluorescence / methods
  • Spectroscopy, Fourier Transform Infrared / methods
  • Staining and Labeling
  • Xylans / chemistry*

Substances

  • Fluorescent Dyes
  • Organotin Compounds
  • Xylans
  • arabinoxylan
  • dibutyltin dilaurate
  • Dimethyl Sulfoxide