Heavy metals detection in river water with cantilever nanobiosensor

Abstract

Heavy metals can be highly toxic depending on the dose and the chemical form. In this context, sensing devices such as nanobiosensors have been presented as a promising tool to monitor contaminants at micro and nanoscale. In this work, cantilever nanobiosensors with phosphatase alkaline were developed and applied to detect heavy metals (Pb, Ni, Cd, Zn, Co, and Al) in river water. The nanobiosensor surface was functionalized by the self-assembled monolayers (SAM) technique using 16-mercaptohexadecanoic acid, N-(3-dimethylaminopropyl)-N′-ethylcarbodiimide (EDC) and N- hydroxysuccinimide (NHS), and phosphatase alkaline enzyme. The sensing layer deposited on the cantilever surface presented a uniform morphology, at nanoscale, with 80 nm of thickness. The nanobiosensor showed a detection limit in the ppb range and high sensitivity, with a stability of fifteen days. The developed cantilever nanobiosensor is a simple tool, suitable for the direct detection of contaminants in river water.

Keywords:

• Self-assembled monolayers (SAM)
• surface
• detection limit
• phosphatase alkaline
• water

Acknowledgements

The authors would like to thank National Council for Scientific and Technological Development (Cnpq), Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (Capes) - Finance Code 001, Fundação de Amparo à Pesquisa do Estado do Rio Grande do Sul (Fapergs),Financiadora de Estudos e Projetos (Finep), URI and Embrapa for their financial and structure support.

Disclosure statement

There are no conflicts to declare.