Imaging of wood tissue by ToF-SIMS: Critical evaluation and development of sample preparation techniques

Abstract

Tissue of Norway spruce wood was investigated by time-of-flight secondary-ion mass spectrometry (ToF-SIMS) and field-emission scanning electron microscopy (FE-SEM). Different sample preparation techniques (including sectioning and drying) traditionally used for SEM analysis were compared and critically evaluated. A high contamination of wood surfaces by polytetrafluoroethylene (PTFE) introduced onto the sample during sectioning was detected by ToF-SIMS. A new protocol was developed and images of wood sections dried in different ways were compared. Main location of Mg, Na, K and Ca, but no lignin in membranes of bordered pits in spruce section surfaces was detected by ToF-SIMS imaging if critical point drying (CPD) or acetone extraction followed by drying under nitrogen flow (AEND) was applied. No specific locations of wood components as well as low signals from metal ions (Mg and Na) were observed on the wood surfaces of freeze-dried (FD) or air-dried (AD) sections. It was found that extractive substances, presenting on surfaces of FD and AD wood section, were evenly distributed on the surfaces and interfered with ToF-SIMS analysis. Our results indicated that ToF-SIMS imaging was critically sensitive to the sample preparation technique and a strict protocol for characterization of metals, lignin and polysaccharides in wood was suggested. (c) 2007 Elsevier B.V. All rights reserved

Keywords

Tof-SIMS; FE-SEM; extractives; FD; wood sections; sample preparation

Published in

Applied Surface Science
2007, volume: 253, number: 18, pages: 7569-7577
Publisher: ELSEVIER SCIENCE BV

SLU Authors

• Daniel, Geoffrey

  • Department of Forest Products, Swedish University of Agricultural Sciences
    

UKÄ Subject classification

Forest Science

Publication identifier

• DOI: https://doi.org/10.1016/j.apsusc.2007.03.059

Permanent link to this page (URI)

https://res.slu.se/id/publ/15168