Chemiluminescence detection for Cu (II) based on 1,10-Phenanthroline-hydrogen peroxide reaction on a PDMS microfluidic chip

Abstract

A simple, rapid and effective method for the determination of copper (II) in water on a PDMS microfluidic chip with chemiluminescence (CL) detection is presented. The CL reaction was based on oxidation of 1,10-phenanthroline by hydrogen peroxide in basic aqueous solution. Polydimethylsiloxane (PDMS) was chosen as material for fabricating the microfluidic chip with two steps lithography method. Optimized reagents conditions were found to be 6.0 × 10−5 mol/L 1,10-phenanthroline, 1.2 × 10−3 mol/L hydrogen peroxide, 6.5 × 10−2 mol/L sodium hydroxide and 2.0 × 10−3 mol/L Hexadecyl trimethyl ammonium Bromide (CTMAB). In the continuous flow injection mode the system can perform fully automated detection with a reagent consumption of only 3.4 μL each time. The linear range of the Cu (II) ions concentration was 1.0 × 10−8 mol/L to 1.0 × 10−4 mol/L, and the detection limit was 9.2 × 10−9 mol/L with the S/N ratio of 3. The relative standard deviation was 2.8 % for 1.0 × 10−6 mol/L Cu (II) ions (n = 8). The most notable features of the detection method are simple operation, rapid detection and easy fabrication of the microfluidic chip.