As the core component of electrochemical sensors, the performance of ion selective electrodes (ISE) directly determines the accuracy and reliability of analysis results. When making a purchase, it is necessary to comprehensively consider multiple factors such as detection targets, application scenarios, technical parameters, and supporting conditions. The following are the key points explained in detail:

1、 Clearly define detection requirements and target ions

Single ion specificity: Prioritize confirming the type of ion to be tested (such as Na ⁺, K ⁺, Cl ⁻, NH ₄, etc.), and select electrodes with high selectivity. For example, the fluoride ion electrode uses LaF3 crystal film, which has high specificity for F ⁻; And pH glass electrodes only respond to H ⁺ activity.

Cross interference assessment: If the sample contains high concentrations of coexisting ions (such as Mg ² ⁺ when measuring Ca ² ⁺), attention should be paid to the electrode selection coefficient (Kij), and low interference models with Kij<0.1% should be prioritized.

Multi parameter synchronous detection: If multiple ions need to be measured simultaneously, composite electrodes or multi-channel systems can be used, but attention should be paid to potential interference between each electrode.

2、 Physical characteristics and environmental adaptability

Sensitive membrane material: Solid film (such as PVC film) resistant to high-pressure sterilization, suitable for biological samples; Liquid film (including filling liquid) has high sensitivity but is prone to leakage.

Electrode diameter and shape: Microelectrodes (Φ<1mm) are suitable for micro sampling, while conventional electrodes (Φ 5-8mm) balance stability and versatility.

Temperature and pressure resistance: Special models with titanium alloy shells and high-temperature resistant cables should be selected for high temperature and high pressure environments (such as oil and gas field exploration).

Corrosion resistant design: Platinum/iridium alloy interface should be selected for strong acid-base or organic solvent systems to avoid corrosion of ordinary metals.

3、 Compatibility of supporting systems

Reference electrode matching: Double salt bridge reference electrode can isolate redox substances in the sample, extending its service life; The flow cell system needs to integrate online reference electrodes.

Unified interface protocol: Confirm that the electrode connector type (BNC/SMA/Swagelok) is compatible with existing instruments, and that digital electrodes support Bluetooth/USB direct connection to computers, preferably.

Calibration solution kit: Standard stock solution and dilution plan should be included with the purchase to facilitate on-site preparation of calibration curves.

4、 Brand and technical service guarantee

Original factory technical support: Priority should be given to brands that provide on-site installation and commissioning, annual preventive maintenance, and customized non-standard electrodes are recommended for complex working conditions.

Consumables supply cycle: Consumables such as membranes and electrolytes need to ensure long-term stable supply, and imported electrodes need to verify domestic agency qualifications.

Data traceability capability: The intelligent electrode with RFID chip can automatically record calibration history, in compliance with GLP/ISO specifications.