Design of wireless sensor node based on a novel hybrid chemical sensor for heavy metal monitoring

A wireless sensor node based on a novel hybrid chemical sensor was designed for heavy metal monitoring. The node consisted of four units that were the transducer unit, the processor unit, the communication unit and the power unit. The hybrid chemical sensor combining microelectrode arrays (MEA) and light-addressable potentiometric sensors (LAPS) on the same silicon chip was used to get redundant data about the concentrations of heavy metal and hydrogen ions in water environment. Multiple linear regression (MLR) with peak currents of Zn²⁺, Pb²⁺ and Cu²⁺ from MEA and equilibrium potentials of Zn²⁺, Pb²⁺, Cu²⁺ and H+ from LAPS as the explanatory variables and the concentrations of Zn²⁺, Pb²⁺ and Cu²⁺ as the response variables was modeled to improve the anti-interference ability.

1. INTRODUCTION

As the world's population soars, coastal ecosystems are increasingly threatened by anthropogenic impacts. A great amount of pollutions are drained into oceans and lakes. Heavy metals are of considerable environmental concern due to their toxicity and cumulative behaviors [1].