Enzyme Method-Based Microfluidic Chip for the Rapid Detection of Copper Ions

Metal ions in high concentrations can pollute the marine environment. Human activities and industrial pollution are the causes of Cu2+ contamination. Here, we report our discovery of an enzyme method-based microfluidic that can be used to rapidly detect Cu2+ in seawater. In this method, Cu2+ is reduced to Cu+ to inhibit horseradish peroxidase (HRP) activity, which then results in the color distortion of the reaction solution. The chip provides both naked eye and spectrophotometer modalities. Cu2+ concentrations have an ideal linear relationship, with absorbance values ranging from 3.91 nM to 256 mu M. The proposed enzyme method-based microfluidic chip detects Cu2+ with a limit of detection (LOD) of 0.87 nM. Other common metal ions do not affect the operation of the chip. The successful detection of Cu2+ was achieved using three real seawater samples, verifying the ability of the chip in practical applications. Furthermore, the chip realizes the functions of two AND gates in series and has potential practical implementations in biochemical detection and biological computing.

Automated summary

The study explores a method for rapid detection of Cu2+ in seawater using an enzyme-based microfluidic technology, which is efficient and shows a linear relationship with Cu2+ concentrations ranging from 3.91 nM to 256 mu M, with a detection limit of 0.87 nM. Successful detection in real seawater samples indicates practical applicability, and the chip also has the potential for practical implementations in biochemical detection and biological computing.