・High sensitivity CV measurement
・Very small sample quantity for EC measurement
・Small and integrated
・Fast response
・Conductivity measurement

Application example

・HPLC measurement electrode
・Electrochemical measurement electrode
・Bio-sensor and chemical sensor electrode
・Chemically modified electrode
・Chemical reaction parameter monitoring electrode

CV measurement using Interdigitated Array Electrodes

IDA Electrode is a pair of band electrode combined and meshes with each other as a generator electrode and collector electrode, therefore it is possible to make an electrochemical redox cycle upon the electrode as showed in figure.
By occurring the redox cycle on electrode increasing electrolysis current to raise measurement sensitivity. In experiment using common electrodes to analyze a small quantity of sample solution, the sample will consumed and exhausted due to electrolysis. However using this Interdigitated array electrode, the oxidation-reduction reaction occur repeatedly so the sample solution will not exhausted.

keyword is diffusion and concentration slope Substance to be oxidized/reduced into the sample solution is transported by diffusion to the electrode surface. Diffusion is the physical phenomenon of the molecular species transport from high to low concentrated region. Interdigitated 65 pairs of generator/collector electrodes set off electrochemical RedOx cycling continuously as shown in Fig.1. This reaction significantly boosts sensitivity of the electrode. Furthermore, samples are preserved when Dual (Red-Ox) Mode is chosen - Not like as Single Mode eats up samples at measurements. In single mode, the decrease of current response become very small　because of the samples substance consumption due to the electrolysis.
Compared with single mode, dual mode measurement has increased in 30 times the current value.	Zoom

The voltammograms of ferrocene samples ((a),(c): 10 µL , (b),(d): 0.2 µL) using IDA electrode ((a),(b): Dual mode; (c),(d): Single Mode) are shown below. As they indicate, measuring mode makes obvious difference on their responses. Dual mode (a),(b) reinforce reduction current at collector electrodes with increase of oxidation current at generator electrodes, in addition, the current value is not affected by the sample volume, only depends on the concentration of the sample. At the measurement (d), comparing with (ｃ), the current response is scarcely obtained, because the sample was consumed during the experiment, indicating that electrode response current of single mode is greatly dependent on the amount of sample solution.

	substrate dimension
	width	12.0±0.1 mm
	length	20.0±0.1 mm
	thickness	0.5 mm
	electrode thickness
	Au	90 nm
	Pt
	C	1.2±0.1 μm
	ITO	100 nm
	adhesive layer - passivation membrane thickness
	Ti	approximately 10 nm （∗only for Au and Pt）
	passivation membrane	about 1 μm

IDA electrode expanded diagram

∗ For Au and Pt, the thickness of the titanium adhesive layer is about 10 nm, resulting in a total thickness of 100 nm.

The handling of until measurement

For the high-sensitivity detection by redox cycle using IDA electrode, dual potentiostat is required.
In addition, CS-3A Cell stand to reduce the noise, and the coating of the reference electrode portion to have the stable reference potential, applying such as silver-silver chloride ink, are recommended.

Handling precautions of IDA electrode

The IDA electrode is a very sensitive product. Here, some advice for the preservation and handling of IDA electrode will be described.

Attention for receiving the product

After receiving the product, it is recommended to test the insulation between the working electrodes using a tester.

Attention for opening the package

Attention for cleaning before use

Attention in measurement

Attention in storage

If long-term storage, put the electrode in the case. Store the case in clean space such as desiccator, away from heat and moisture.

CAUTION

Any defects in the appearance (ex: pinhole on lead area, burr of glass) without any influence to the measurement, are not covered under warranty.