Sensitive Detection of Sulfide Ions in Aqueous Systems

The accurate measurement of sulfide ions (S²–) in water is critical for environmental monitoring, industrial process control and public health. Sensitive detection methods must overcome challenges such as interference from other ions, rapid oxidation of sulfide and the need for in situ or real-time measurement in complex matrices. Advances in sensor design have leveraged electrochemical, optical and chromatographic techniques to achieve low detection limits, wide dynamic ranges and robust performance in freshwater, seawater, wastewater and biological fluids. Key trends include the integration of nanostructured materials to enhance signal transduction, the development of ratiometric and multi-modal platforms for improved selectivity, and the refinement of sampling protocols to minimise artefacts. Together, these efforts are driving towards field-deployable devices capable of rapid, reliable and cost-effective monitoring of sulfide levels across diverse aqueous environments.

Research from Nature Portfolio

Studies have demonstrated that an amperometric inhibitive biosensor constructed with nanoporous gold and horseradish peroxidase can sensitively quantify sulfide by exploiting competitive inhibition of enzymatic activity. The bioelectrode exhibits a wide linear response over sub-micromolar to tens of micromolar concentrations, with a detection limit in the low nanomolar range. Reversibility of the inhibition allows rapid regeneration of the sensor surface, enabling repeated measurements with minimal loss of activity. Application to environmental samples has confirmed accurate sulfide determination in complex media, highlighting the promise of enzyme-based electrochemical platforms for real-time monitoring.

Sensitive Detection of Sulfide Ions in Aqueous Systems publication trend

The graph below shows the total number of articles in sensitive detection of sulfide ions in aqueous systems across all publications each year (not limited to Nature Index journals).

Technical terms

Amperometric biosensor: An electrochemical device that measures current changes resulting from enzymatic reactions inhibited or catalysed by target analytes.

Nanoporous gold (NPG): A high-surface-area metal scaffold produced by selective dealloying, used to immobilise enzymes and enhance electron transfer in sensors.

Limit of detection (LOD): The lowest concentration of analyte that can be distinguished from background noise with defined confidence.

Graphene quantum dots (GQDs): Nanoscale fragments of graphene exhibiting size-dependent fluorescence, used as optical reporters in chemical sensing.

Ion chromatographic pulsed amperometric detection (IC-PAD): A separation technique coupled with time-resolved amperometric measurement, enabling selective detection of ionic species in complex mixtures.

References

1. Amperometric inhibitive biosensor based on horseradish peroxidase-nanoporous gold for sulfide determination. Scientific Reports (2016).
2. Microsensor for total dissolved sulfide (TDS). Chemosphere (2023).
3. Sensitive Detection of Sulfide Ion Based on Fluorescent Ionic Liquid–Graphene Quantum Dots Nanocomposite. Frontiers in Chemistry (2021).
4. Use of ion chromatographic pulsed amperometric method (IC-PAD) for measuring aqueous sulfide in synthetic and real domestic wastewater. Chemosphere (2022).