THE SORPTION OF HG(II) ONTO SINGLE-WALL CARBON NANOTUBES EVALUATED WITH ESCHERICHIA COLI pMerR ':: LUX BIOSENSOR

Issue: 
12
Year: 
2017

D.G. Deryabin
Dr.Sc. (Med.), Professor, MD, Professor, Chief Research Scientist, Laboratory of Microbiology,
All-Russian Research Institute of Beef Cattle Breeding (Orenburg)
E-mail: dgderyabin@yandex.ru
K.S. Inchagova
Junior Research Scientist, Department of Feeding, All-Russian Research Institute of Beef Cattle Breeding;
Post-graduate Student, Department of Biochemistry and Microbiology, Orenburg State University
E.A. Stroganova
Senior Lecturer, Department of Chemistry, Orenburg State University
I.V. Manukhov
Dr.Sc. (Biol.), Professor, Head of the Laboratory of Molecular Genetics,
Moscow Engineering Physics Institute (State University) (Dolgoprudny)

Background. Carbon allotropes are traditionally used as polyvalent physicochemical antidotes, and carbon-based nanomaterials are investigated extensively now. Aim. The goal of this study is to evaluate the sorption of mercury ions on single-wall carbon nanotubes (SWCNTs) that was done according by bacterial lux-biosensor reaction. Methods. SWCNTs functionalized with F or NH2 groups were used to investigate the removal of Hg(II) ions from aqueous solutions. The recombinant luminescent strain Escherichia coli K12 MG1655, carrying the hybrid plasmid pMerR ':: lux with the Photorhabdus luminescens luxCDABE-genes cassette cloned under inducible mer-operon promoter was used for residual Hg(II) quantitative detection. Results. The high sorption capacity qE = (2 ± 0.2) x10- 6 mg / mg of the F-SWCNT was shown, while Hg (II) retention on the NH2-SWCNT was very low. The adsorption isotherm data for FSWCNT could be well described by the Temkin equations (sorption on inhomogeneous surface involving activated cites). X-ray phase analysis indicated the mercury ions stabilization in the sorbent matrix in HgF2, Hg2OCl, Hg4OCl2, and Hg2Cl2 forms. Discussion. The primary interaction between mercury ions and modifying groups on F-SWCNT surface may be due to the electrostatic forces, while final Hg stabilization in the sorbent matrix suggests additional hydrodysis and recovery reactions. These data has shown possibilities of F-SWCNT and other halogenated nanotubes as effective Hg (II) sorbents as well as analytical capabilities of the bacterial luminescent biosensor E. coli pMerR ':: lux for sorption evaluation.

Keywords: 
Key words: lux-biosensors
mer-operon
mercury
carbon nanotubes
sorption.