A novel cadmium-containing wastewater treatment method: Bio-immobilization by microalgae cell and their mechanism

J Hazard Mater. 2019 Jul 15:374:420-427. doi: 10.1016/j.jhazmat.2019.04.072. Epub 2019 Apr 22.

Abstract

Heavy metal cadmium (Cd) has drawn tremendous comcern due to its rigorous environmental and health hazards. Herein, we have presented an efficient and economical strategy for the removal and recycling of hazardous Cd ions using microalgae cells as the bioreactors. Remarkably, the green bio-platform for the bioproduction of CdSe nanoparticles (NPs) was developed depending on their orderly regulated and sustainable cellular environment. The biofabricated CdSe NPs manifested favorable photoluminescence properties, and presented well monodispersed spherical morphology and certain crystallinity structure with mean size of smaller than 7 nm. Especially, the fluorescence "turn off" sensing system based on the CdSe NPs was established to detect Hg2+. The nanosensor enables the quantitative analyses of Hg2+ with a linear range of 0-2.0 μM and a detection limit of 0.021 μM. Furthermore, it was preliminarily speculated that the reducing biomolecules in the algae cells could be involved in the formation of CdSe NPs. This work not only provides new insights into the removal and recycling of hazardous Cd ions, but also brings a promising route for biosynthesis of CdSe NPs.

Keywords: Biofabrication; CdSe NPs; Hg(2+) sensor; Mechanism; Microalgae cells.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Biodegradation, Environmental
  • Bioreactors
  • Cadmium / analysis*
  • Cadmium Compounds / analysis
  • Fluorescent Dyes / analysis
  • Ions / analysis
  • Limit of Detection
  • Mercury / analysis
  • Metal Nanoparticles / analysis
  • Metals, Heavy / analysis
  • Microalgae / metabolism*
  • Selenium Compounds / analysis
  • Waste Disposal, Fluid / methods*
  • Wastewater / analysis
  • Water Purification / methods*

Substances

  • Cadmium Compounds
  • Fluorescent Dyes
  • Ions
  • Metals, Heavy
  • Selenium Compounds
  • Waste Water
  • Cadmium
  • Mercury