Abstract

A whole cell based biosensor is prepared by immobilizing Chlorella sp. microbes over glassy carbon electrode. The proposed biosensor is optimized for characteristics like; substrate concentration, pH, response time, durability, etc. The electrode responds linearly in concentration range of 10-14 M to 10-6 M for zinc, copper, cadmium, cobalt and nickel ions. Relative selectivity of the metal ions can be ordered in following sequence: Zn2+ >> Cu2+ ≈ Cd2+ > Co2+ > Ni2+. The biosensor has a life time of 14 days, after which, its analytical properties do not remain stable.

Keywords: Atomic absorbtion spectrometry, biosensor, bovine serum albumin, Chlorella sp., chronoamperometry, glutaraldehyde, glassy carbon electrode, heavy metal ions, immobilization, interference, real life samples, ultra- trace level measurement