Detection

Peak finding

Locate the peaks in a voltammogram and report their potential, current, and charge.

The position of a voltammetric peak identifies the species and its height measures the amount. Peak finding in Studio reads both from the scan and integrates the charge under each peak at the same time.

The same routine works on CV, DPV, and SWV.

When to use it

Quantitative analysis: ip scales with concentration, and the peak charge scales with the amount of material reacted.
Scan-rate studies: plotting ip against √ν gives the Randles–Ševčík diffusion coefficient.
Reversibility: the separation of the anodic and cathodic peaks (ΔEp) and the ratio of their currents.
Calibration series: running Pk on each scan and passing the peak currents to a calibration curve in the Publication Workbench.

How it works

Studio scans the voltammogram for local maxima (anodic peaks) and minima (cathodic peaks), places a marker at each one, and records the potential and current.

For each peak it also finds the inflection points on either side, draws a baseline between them, and integrates the area between the trace and the baseline to give the charge Q.

Parameters

Detection

Automatic. Anodic and cathodic peaks are found without any threshold to set.

Baseline

Drawn automatically between the inflection points on either side of the peak. The endpoints are shown on the plot and can be moved in the Pk window.

Example

Quantify dopamine from a DPV calibration series

Load the DPV scans (five concentrations) into Studio.
Click the Pk badge on each scan. Studio reports Ep, ip, and Q for every peak.
Open the Publication Workbench and start a calibration from the five scans. The peak currents fill the Signal column.
Type in the concentrations. The fit reports slope, intercept, R², and the limit of detection.

Result. A calibration slope, intercept, R², and limit of detection, with every peak current traceable to its scan.

In Sensitify Studio

Peak finding opens from the Pk badge next to any voltammetry experiment in the right sidebar. The detected peaks are marked on the plot and their values appear in the peak tooltip.

Step-by-step instructions: Find peaks