Ionic Strength Adjustment Buffers (ISAB) are required to accurately measure ions with an ion selective electrode (ISE). Each ISAB has been specially formulated to allow the buffering of all samples and standards to the same Ionic Strength without interfering with the ion measurement. The ISABs will come in a 500ml leak-proof bottle with an inner seal. The addition of 2ml of ISAB per every 100ml of standard and sample is recommended, please get in touch with our tech support team support@Camlab.co.uk for help on your particular application.
The ionic strength of standards and samples are not the same thereby the ability of ions to freely move around varies from sample to sample. This means that the effective activity of ions will vary between these solutions. Ion selective electrodes work by sensing ion activity when ions come into contact with the sensor surface. To ensure that all ions in the solution have an equal probability of contacting the ISE the total ionic strength of all solutions should be equal (as close to as possible). This is achieved by adding a small volume of ISAB (Ionic Strength Adjustment Buffer) to a fixed volume of all standards and samples.