BI-ZTU Automatic Titration System for Zeta Potential Instrumentation

Brookhaven Instruments offers the BI-ZTU Automatic Titration System option for the NanoBrook benchtop particle characterization instruments that have the zeta potential measurement option. The autotitrator has been designed for the automatic determination of the isoelectric point (IEP) in colloidal materials and the determination of optimal dosage for coagulation with a flocculent. The BI-ZTU can also be used for studying the influence of ionic strength of a salt solution on the zeta potential of particles.

The BI-ZTU incorporates four precision-controlled, dosing pumps that are made of chemically resistant materials allowing the flexibility to use wide variety of titrants.  For an acid/base titration the BI-ZTU utilizes a combination pH electrode for tracking of zeta potential at different pH values. Two of the four dosing pumps are used for an acid and the other two for a caustic. The use of two dosing pumps allows for different concentration of titrants to be used.

Example of pH Titration Measurement Results

Example of pH titration versus zeta potential. Image Credit: Brookhaven Instrument Corporation

The BI-ZTU Autotitrator can also be used to determine the optimal dosage of a flocculent for the coagulation of particles in the treatment of surface drinking water to reduce turbidity to permitted levels. Traditionally jar testing is done and is subjective. With the BI-ZTU it is possible to determine the amount flocculent to add to obtain a zeta potential between 0 and -10 mV.  Within in this range the addition of flocculent achieves the targeted reduction in turbidity. Zeta potential greater than 0 mV will have a marginal impact on turbidity reduction.

Features at a Glance

•Four metering pumps for precision dosing to selected pH endpoints
•pH electrode input for potentiometric titrations
•Flow through cell with zeta potential electrode for continuous measurements

Integrated, Simple Software

•The titrator command will show up in the main menu bar of Particle Solutions software when the BI-ZTU is connected to a NanoBrook compatible instrument that has the zeta potential measurement option. The user is automatically guided through an auto-titration experiment by the software. Step-wise guidance is provided for inexperienced users through an easy-to-use dialog box.


  • Range  pH 2 to pH 12
  • Flow Cell  Supplied with BI-ZELF-B plastic flow cell that fits into instrument   square sample cell holder. Optional BI-ZPS flow cell and   90PFC quartz flow cell for particle sizing.
  • Tubing  1.00 mm (0.040″) I.D. Teflon, PEEK, and EPDM.
  • External Fittings  Luer Lock
  • Size   310 x 180 x 290 mm
  • Power  110/115/220/240 VAC, 60/60 Hz, 25 Watts
  • Certifications  CE Marked
  • Compatibility  NanoBrook 90Plus Zeta, 90Plus PALS, ZetaPlus, ZetaPALS, and Omni.
  • Ordering Information: BI-ZTU is supplied with BI-ZTU-B plastic sample cups, BI-ZELF plastic electrode assembly, BI-ZELF-B plastic flow cell to be used with BI-ZELF, BI-ZTUpH combination pH electrode, and (4) 100 ml screw-cap titrant reservoir bottles.

Other Equipment by this Supplier

While we only use edited and approved content for Azthena answers, it may on occasions provide incorrect responses. Please confirm any data provided with the related suppliers or authors. We do not provide medical advice, if you search for medical information you must always consult a medical professional before acting on any information provided.

Your questions, but not your email details will be shared with OpenAI and retained for 30 days in accordance with their privacy principles.

Please do not ask questions that use sensitive or confidential information.

Read the full Terms & Conditions.