Titrators are used to determine the concentration of a substance (analyte), which is dissolved in a sample. A reagent (titrant) is added gradually in a known volume to the sample until a chemical reaction reaches its endpoint, which is detected by a sensor.

How titrators work step-by-step:

1. Sample addition: The sample is added to a vessel, often with a stirrer to ensure homogeneity.
2. Titrant addition: The titrant is added manually or automatically in controlled volumes.
3. Measurement & monitoring: Sensors continuously monitor the reaction. The titrator tracks changes in solution properties (e.g., voltage, color, conductivity) to detect the equivalence point.
4. Endpoint detection: The endpoint is the moment when the reaction is complete.
5. Result calculation & reporting: The titrator calculates the concentration of the analyte based on the volume of titrant used and generates a digital report.

Various sensors are available to monitor the reaction depending on the type of titration you are performing. Metrohm offers sensors for photometric, thermometric, redox, precipitation, complexometric, surfactant, aqueous or non-aqueous acid-base titration.

Check out our Webinar Center and our blog to learn more about titration:

Webinar: Basics of titration

Blog: Titration – definition and principles

Blog: Best practices for electrodes in titration

In summary, the main benefits of an autotitrator are:

• Speed and throughput: Faster analysis and higher sample throughput
• Accuracy and reproducibility: Automated dosing and endpoint detection minimize human error
• Efficiency: Frees lab personnel from repetitive tasks
• Safety: Minimizes chemical exposure
• Data management: Digital reports and integration with LIMS/ERP systems
• Scalability: Modular accessories and automation options adapt to changing workloads

Learn more about autotitrators:

White Paper: Manual vs. Automated Titration: Benefits and Advantages to Switching

Webinar: The benefits of automating your titration applications

Blog: Why consider automation – even for simple titrations

Blog: How to transfer manual titration to autotitration

Choosing the right titrator depends on your sample type, analytical goals, and lab environment. Here are the key factors to consider:

Our titration experts are happy to assist you with your questions:

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The most common indication methods for automated titrations are potentiometric and photometric endpoint (EP) determination.

In potentiometric EP determination, the difference in potential is measured: The concentration-dependent potential of a solution is measured using an indicator electrode against a reference potential, which is measured using a reference electrode. Combined sensors including both indicator and reference electrode are also available.

In photometric EP determination, a photometric sensor, such as the Optrode from Metrohm, is used to determine the change in intensity at a particular wavelength of a light beam passing through a solution.

Another kind of titration that is less well known is thermometric titration. Thermometric EP determination relies on detecting temperature changes during the titration reaction. A highly sensitive temperature sensor monitors the solution, and the endpoint is identified by a sudden change in temperature, which occurs due to the exothermic or endothermic nature of the reaction. This method is especially useful for titrations where no suitable electrode or photometric indicator is available.

Learn more about potentiometric, photometric, and thermometric endpoint determination in our blog:

Blog: Recognition of endpoints (EP)

Blog: Thermometric titration – the missing piece of the puzzle

Webinar: Thermometric titration

Yes, entry-level Metrohm titrators (i.e., Eco Titrators) deliver reliable accuracy when paired with proper electrodes and validated methods.

The accuracy of titrations does not only depend on the instrument, it is the sum of several factors that contribute to it:

• Choice of a suitable electrode or indication method
• Choice of a suitable cylinder volume
• Choice of a suitable titration mode
• Accuracy of sample size (weighing/pipetting)
• Homogenization of the sample
• Electrode cleaning and maintenance
• Burette maintenance
• Other factors, depending on the specific titration method

An overview on how to get correct and accurate titration results can be found here:

Blog: How to avoid titration errors in your lab

Blog: Validation of  titration methods

Webinar: Avoid titration mistakes through best practice sensor handling

Webinar: Troubleshooting titration: essential know-how for quality results

Metrohm’s Ti-Touch and OMNIS titrators offer audit trails, user management, and secure data handling for full regulatory compliance to 21 CFR Part 11.

Stand-alone titrators (without PC software): Ti-Touch

Software-controlled titrators: OMNIS

Validating a titration method ensures that the procedure delivers accurate, reproducible, and reliable results – especially when transitioning from manual to automated titration. Metrohm recommends following the validation framework outlined in USP General Chapter <1225> Validation of Compendial Procedures and ICH Guidance Q2(R1) Validation of Analytical Procedures: Text and Methodology, which includes the following key steps:

• Perform standardization of the titrant using a primary standard or a pre-standardized solution
• Assess the accuracy and precision of the titration results by performing reference measurements
• Verify the linearity of your results, i.e., that the titration results are proportional to the analyte concentration across the expected range
• Demonstrate specificity, i.e., that the method can accurately measure the analyte without interference from impurities, excipients, or degradation products.

Find more information:

Blog: Validation of titration methods

White paper: Recommendations for titration methods validation

Modern titration systems offer various data formats for transferring titration data to an external software (LIMS / ERP / ELN). The most common formats are:

• PC/LIMS report
• XML report
• PDF
• CSV

Any Metrohm titrator offers at least one of these options, either by transferring the corresponding data in a corresponding file to a USB memory stick or directly to a computer/network directory.

The OMNIS Software offers a convenient and secure data exchange between OMNIS and any 3^rd party software (e.g., LIMS, ERP, ELN) by direct transfer based on the REST software architecture.