Ion Selective Electrodes

Ion-selective Measurements

WTW offers ...

  • Laboratory ISE Benchtop Meters
  • Portable ISE Meters
  • Ion-selective Electrodes

Ion-selective measurement is a method for determining the concentration of dissolved ions. Potassium ions, sodium ions, fluoride or chloride are examples of such cations and anions that are directly measured in solutions. Indirect methods such as titration allow the determination of aluminum, nickel ions, or sulfate.

The wide range of possible applications include the measurement of fluoride concentration according to DIN 38 405. Chloride content determination in concrete samples or nitrate concentration determination in fruit juices are further examples of the ways in which ion-selective measurement technology can be applied. An introduction to ion-selective measurement technology, as well as application reports, are available on our CD-ROM entitled “Principles of measurement technology”. 



  • precise pH/ISE benchtop meter with enhanced ISE methods for concentration measurement with ion selective electrodes.
  • Simultaneous measurements of pH, ion concentration or ORP 
  • Flexible and convenient data transfer 
  • Visualization of the optimum measuring range supports correct measurements (CMC function). 

The well-equipped and convenient WTW inoLab® pH/ION 7320 Benchtop Meter is the right meter for precision measurements and the automatic documentation as per GLP/AQA in quality labs in all industries. Upon request, also available with optional built-in printer. 

Flexible and high performance: 

  • up to 5-point calibration for pH 
  • up to 7-point calibration with ion measurement, also non-linear 
  • Blank value correction, increment methods: Known addition, known subtraction, sample addition, sample subtraction 
  • Concentration values in different units 
  • Selectable AutoRead criterion 
  • DIN or BNC version 
  • Backlit graphic display with CMC display
    Electrochemical concentration measurement with ionselective electrodes
    Ion selective electrodes for the electro-chemical concentration determination of selected ions with combined electrodes

    - Cost-effective process for low amounts of samples
    - Wide selection of electrodes for different ions
    - Easy handling by combined electrodes
    Combined ISE electrodes series 800
    The combined electrodes type 800 are excellent in their handling and offer the additional opportunity to also measure small sample volumes, as the ion selective and the reference electrodes are combined in a compact rod. Furthermore, they are convincing with their exceptionally great price/performance ratio.
    Ag/S 800 BNC: Silver/Sulphide electrode, 1 m BNC cable
    Ag/S 800 DIN: Silver/Sulphide electrode, 1 m DIN cable
    Br 800 BNC: Bromide electrode, 1 m BNC cable
    Br 800 DIN: Bromide electrode, 1 m DIN cable
    Ca 800 BNC: Calcium electrode, 1 m BNC cable
    Ca 800 DIN: Calcium electrode, 1 m DIN cable
    CA 800/AT: exchange head Calcium electrode
    Cl 800 BNC: Chloride electrode, 1 m BNC cable
    Cl 800 DIN: Chloride electrode, 1 m DIN cable
    CN 800 BNC: Cyanide electrode, 1 m BNC cable
    CN 800 DIN: Cyanide electrode, 1 m DIN cable
    Cu 800 BNC: Copper electrode, 1 m BNC-cable
    Cu 800 DIN: Copper electrode, 1 m DIN-cable
    F 800 BNC: Fluoride electrode, 1 m BNC cable
    F 800 DIN: Fluoride electrode, 1 m DIN cable
    K 800 BNC: Potassium electrode, 1 m BNC cable
    K 800 DIN: Potassium electrode, 1 m DIN cable
    K 800/AT: exchange head potassium electrode
    NO 800 BNC: Nitrate electrode, 1 m BNC-cable
    NO 800 DIN: Nitrate electrode, 1 m DIN-cable
    NO 800/AT: exchange head Nitrate electrode
    NH 500/2: Ammoniumgas sensitive electrode, S7 plug head