Determination of bismuth and copper using adsorptive stripping voltammetry couple with continuous wavelet transform

Area of Science:

• Analytical Chemistry
• Electrochemistry
• Environmental Science

Background:

• Accurate determination of bismuth and copper is crucial for environmental and health monitoring.
• Overlapping voltammograms of Bi(III) and Cu(II) pose a significant challenge in simultaneous analysis.
• Existing methods may struggle with interference and matrix effects in complex samples.

Purpose of the Study:

• To develop a new method for the simultaneous determination of bismuth and copper.
• To overcome the challenge of overlapping voltammograms using advanced signal processing.
• To achieve low detection limits and reliable quantification in real samples.

Main Methods:

• Adsorptive stripping voltammetry using a hanging mercury drop electrode (HMDE).
• Complexation of Bi(III) and Cu(II) with chromazur-S.
• Application of Continuous Wavelet Transform (CWT) with Symlet4 (Sym4) wavelet filter for signal separation.
• Optimization of wavelet parameters (dilation, filter) for enhanced resolution.
• Utilizing the standard addition method to address matrix effects for Bi(III) determination.
• Employing a calibration curve with CWT coefficients for Cu(II) determination.

Main Results:

• Successful separation of overlapping Bi(III) and Cu(II) voltammograms using CWT.
• Achieved low detection limits: 0.10 ng/mL for bismuth and 0.05 ng/mL for copper.
• Established linear dynamic ranges: 0.1-30.0 ng/mL for bismuth and 0.1-32.0 ng/mL for copper.
• Demonstrated the effectiveness of the standard addition method for matrix effects on Bi(III).
• Validated the method's applicability to real samples, including water and human hair.

Conclusions:

• The proposed CWT-assisted adsorptive stripping voltammetry method provides a sensitive and selective approach for simultaneous Bi and Cu determination.
• The method effectively resolves spectral interferences and mitigates matrix effects, offering accurate quantification.
• This technique shows significant potential for routine analysis of bismuth and copper in diverse environmental and biological matrices.