Ion Meters

An ion meter measures the concentration of specific ions in a solution. It uses an ion-selective electrode that responds selectively to a particular ion in the solution being measured. The electrode generates a small electrical potential in response to the target ion's concentration in the solution.

An ion meter can measure the concentration of various ions, such as calcium, chloride, fluoride, nitrate, potassium, sodium, and others. They are essential tools in various fields, such as water quality testing, environmental monitoring, medical research, and the food and beverage industry to maintain the quality of products and the safety of consumers.

Ion measurement using ion-selective electrodes (ISEs) is primarily intended for liquid samples, as the samples need to be in solution to measure ion concentrations accurately.

However, there are methods to extract ions from solid samples into a liquid phase for measurement. For example, in the case of soil samples, an extraction process can be employed to dissolve the ions of interest into a liquid solution for subsequent ion measurement using ISEs.

Ion meters are generally very accurate measuring devices. The accuracy of the SevenExcellence meter for measuring the ion concentration is ±0.5%. However, it is important to note that the accuracy of meters may vary depending on the instrument, the specific ion being measured, and other factors, such as the quality of the reference solutions used for calibration and the stability of the electrode over time.

It is recommended to regularly calibrate and maintain the electrode to ensure the most accurate results. For more details, refer to the respective manuals and product brochures.

To calibrate an ion meter, you should follow these general steps:

1. Take a defined volume of samples and standards and add the appropriate amount of ISA solution to all of them.
   
2. Stir the samples and calibration standards uniformly, using gentle stirring to avoid air bubbles. A strong vortex should be avoided as it can cause air bubbles to form.
3. Immerse the ISE properly, making sure that the reference junction is completely immersed in the solution.
4. Always rinse the electrode with deionized water between measurements to prevent sample carryover.
5. Shake the electrode gently to remove the rinsing water and dab it dry with a low-lint tissue. Do not wipe or rub the electrode sensing element.
6. Verify the electrode calibration every two hours by placing the electrode in a fresh aliquot of the least concentrated standard used for calibration.
7. Recalibrate the electrode if the value changes more than 2% (for solid-state membrane ISE) or 4% (for polymer membrane ISE).

For more information, refer to our ISE theory guide.

When choosing the right ion meter for your needs, consider the application, accuracy, measurement range, calibration, temperature compensation, durability, and price. Choose an ion meter that meets your needs and budget without sacrificing accuracy or quality.

METTLER TOLEDO's Good Electrochemistry Practice is a complimentary document that can help you find the ideal system, including ion meters, sensors, buffers, and suitable services based on your specific requirements.

An ion meter offers several benefits that make it a valuable tool in various industries, including environmental science, pharmaceutical research, food and beverage production, agriculture, water treatment, and many others.

Ion measurement is a selective technique designed to measure specific ions. It provides relatively faster and more accurate measurements and is a non-destructive sample. Ion meters are easy to operate and can measure a wide range of concentrations.

Ion meters are designed to measure the concentration of various ions in a solution. Some common types of ions that can be measured with an ion meter include:

• Hydrogen ion (H+)
• Hydroxide ion (OH-)
• Sodium ion (Na+)
• Potassium ion (K+)
• Calcium ion (Ca2+)
• Magnesium ion (Mg2+)
• Chloride ion (Cl-)
• Nitrate ion (NO3-)
• Sulfate ion (SO42-)
• Ammonium ion (NH4+)

These ions are commonly found in various solutions, including soil, water, biological fluids, and industrial process streams. To know different types of sensors that are available, please visit our page: Ion-Selective Electrode: For a Wide Range of ISE Applications (mt.com)

You can purchase ion meters from various scientific and laboratory equipment suppliers, as well as online retailers.

METTLER TOLEDO offers a variety of intuitive and user-friendly ion meters that can accurately measure ion concentration, pH, conductivity, ORP/redox, and dissolved oxygen. Our ion meter range caters to diverse applications.

To find the right ion meter for your needs, browse our selection online and contact our sales team for a personalized quote. Our team is committed to helping you find the best solution for your specific requirements.