Zeta Potential Analyzer with Autotitrator

What is the Zeta Potential Analyzer with Autotitrator?

A zeta potential system integrated with a multi-purpose autotitrator that adjusts pH, conductivity or additive concentration between measurements. It automates isoelectric point, stability window and surfactant or polymer dosing studies, replacing manual pH series that are slow and prone to error.

Overview

This variant combines an electrophoretic or PALS measuring cell with one to three titrant pumps, a magnetic-stirred vessel, pH and optionally conductivity probes, and a peristaltic or syringe pump that circulates the sample through the cell. Software runs programmed pH series, typically from pH 2 to 12, and records zeta potential and size at each point, plotting curves and reporting isoelectric points. Autotitration improves reproducibility and reduces sample consumption compared with preparing individual vials. Typical sample volume is 10 to 50 mL. Titrant concentrations of 0.01 to 0.25 M acid and base are common, and the third channel can dose surfactant or salt for conductivity scans. Probe calibration with buffers and careful flushing between steps are required to prevent carry-over and bubble formation.

How does it work?

Charged particles in a liquid are surrounded by an electrical double layer. The zeta potential is the potential at the slipping plane of this layer, and cannot be measured directly. Electrophoretic light scattering applies an electric field and measures particle velocity from the Doppler shift of scattered laser light; electrophoretic mobility is then converted to zeta potential by the Smoluchowski or Hückel approximation, or the Henry function for intermediate cases. Phase analysis light scattering improves sensitivity by measuring phase rather than frequency shift. Streaming potential instruments force electrolyte through a capillary or plug and measure the generated potential difference for solids. Electroacoustic methods detect sound waves generated by an applied alternating field in concentrated suspensions. Key components include the laser, electrodes and cell, temperature control and often a titrator.

What are the key features?

• One to three titrant channels for acid, base and additive
• Integrated pH and conductivity probes with automatic compensation
• Sample circulation pump with bubble trap
• Programmable pH, conductivity and concentration scans
• Automatic curve plotting and isoelectric point calculation
• Cleaning and flushing routines between titration steps

What are the technical specifications?

A typical zeta potential analyzer with autotitrator configuration offers titrant channels of 1–3, pH range of 2–12 (probe dependent), pH accuracy of ± 0.02 after calibration, sample volume of 10–50 mL, dispensing resolution of ≥ 1 µL step and titrant concentration of 0.01–0.25 M. Values are indicative of the product class; the exact figures for each configuration are confirmed on the quotation and the calibration documents supplied with the instrument.

Which applications is it used for?

The Zeta Potential Analyzer with Autotitrator is used in isoelectric point determination of oxides and polymers, flocculant and coagulant dose optimisation, surfactant and polymer adsorption studies, battery and ceramic slurry stabilisation and protein pH stability mapping. Across the wider Zeta Potential Analyzers class, laboratories also deploy it for colloidal stability of emulsions and suspensions, protein and biologic formulation screening and water and wastewater coagulation control.

Which standards and certifications apply?

Relevant standards and methods include ISO 13099-1, ISO 13099-2, ISO 13099-3, ASTM D4187, GB/T 32671 and ISO 13320. Certification candidates for this model are CE and ISO 9001 manufacturing; each is to be confirmed for the specific configuration before shipment, and certificates are supplied only where they have been issued.

Zeta potential depends on pH, ionic strength, temperature and sample history, so each report should state dispersant, pH, conductivity and temperature. Use low-conductivity, filtered dispersants and avoid bubbles at the electrodes; high salt can cause electrode polarisation and sample heating. Verify performance periodically using a zeta potential transfer standard, typically around −42 mV, and follow the supplier's interval. Clean cells thoroughly, since contamination and electrode degradation alter results. Gold or palladium electrodes and disposable capillary cells simplify maintenance. For regulated use, carry out IQ/OQ/PQ and maintain audit trails. Report the model used to convert mobility to zeta potential.

How do I select the right Zeta Potential Analyzer with Autotitrator?

Choose the autotitrator variant when measurements across a pH, conductivity or additive series are frequent, and reproducibility matters more than a single-point check. Specify the pH range, number of titrant channels, sample volume, chemical compatibility of tubing, solvent type and whether particle size is also required. Single-point screening can be done on a standalone analyzer.

How does it compare with other Zeta Potential Analyzers variants?

Begin with the sample type. Dilute colloids and macromolecules suit electrophoretic light scattering; very low-mobility or high-conductivity samples benefit from phase analysis light scattering. Concentrated opaque suspensions, such as slurries, need electroacoustic methods, and flat or fibrous solids need streaming potential. If isoelectric point or pH dependence is required, choose a system with an automatic titrator. Check the required size range, conductivity limits, minimum sample volume and whether non-aqueous solvents are used, since the dielectric constant must be known. Decide if zeta potential alone is enough or whether combined size measurement is needed. Also weigh software validation support, cell durability and cost of disposable cells, and whether ISO 13099 conformity is expected in your methods.