Metal–biomass interactions: a comparison of visualisation techniques available in South Africa

  • B. A. Moore Institute ofWater Research, Rhodes University, P.O.Box 94,Grahamstown 6139, South Africa. Formerly:Department of Biochemistry, Microbiology and Biotechnology, Rhodes University.
  • C. Mack Golder and Associates, P.O. Box 6001, Halfway House 1685, South Africa. Formerly:Department of Biochemistry, Microbiology and Biotechnology, Rhodes University.
  • J. R. Duncan Dean of Research, Rhodes University, P.O.Box 94, Grahamstown 6139, South Africa.
  • J. E. Burgess Water Research Commission, Private Bag X03, Gezina 0031, South Africa. Formerly:Department of Biochemistry, Microbiology and Biotechnology, Rhodes University.

Abstract

The interaction of metals and biological materials is of interest for reasons such as metal recovery, toxicity and production of high-value products such as gold and platinum nanoparticles. Understanding the way in which metals interact with the biomass surface and intracellular components provides insights into the biosorption and bioaccumulation processes and increases the potential for process optimisation. Three technologies are available for the qualitative visualisation of metal–biomass interactions in South Africa, namely, micro-PIXE, transmission electron microscopy and scanning electron microscopy coupled with energy-dispersive analysis of X-rays. Each technique provides unique information and has specific shortcomings which should be taken into account when selecting the appropriate technology. This paper focuses on evaluating the various techniques.