Metrohm 905/907 Titrando Series Automatic Potentiometric Titrator

Overview

The Metrohm 905/907 Titrando Series represents the culmination of over four decades of electrochemical instrumentation engineering, integrating Metrohm’s proprietary *Intelligent Technology* platform into a modular, fully automated potentiometric titration system. Designed for high-throughput laboratories requiring regulatory compliance and method reproducibility, these instruments operate on the fundamental principle of potentiometric endpoint detection—measuring the potential difference between a reference and an indicator electrode as a function of titrant addition. The system supports classical acid-base, redox, precipitation, and complexometric titrations, as well as specialized applications including Karl Fischer volumetric water determination (KF) and controlled-potential (STAT) electrolytic titrations. Unlike conventional titrators relying on analog signal transmission, the 905/907 architecture employs digital communication across all critical subsystems—electrodes, dosing units, stirrers, and interface modules—enabling real-time calibration traceability, automatic component authentication, and embedded GLP data integrity.

Key Features

• Smart Component Architecture: All major peripherals—including electrodes, Dosino™ dosing units, and measurement cables—contain embedded microchips that store calibration history, usage logs, and identification metadata. This ensures full traceability and eliminates manual configuration errors.
• Dosino™ Dosing Technology: Patented multi-channel peristaltic-free liquid handling system mounts directly onto reagent bottles via standardized adapters. Its transparent housing enables visual bubble detection; automated rinsing and priming routines eliminate manual disassembly for maintenance.
• Modular Expansion Capability: Four MSB (Metrohm Serial Bus) ports support daisy-chained integration of up to two 800 Dosino™ units (each accommodating two 807 dosing modules), four 801 magnetic stirrers, or mixed configurations of 804 titration stands (with 802 rod stirrers) and 803 KF stands.
• Regulatory-Ready Software Stack: tiamo™ software provides role-based access control, electronic signatures, full audit trail (including method versioning, user actions, and timestamped raw data), and 21 CFR Part 11 compliant electronic records—validated for GMP/GLP environments.
• Multi-Mode Titration Engine: Native support for DET (dynamic equivalence point detection), MET (fixed-volume incremental addition), and SET (target-value termination), plus KF volumetric and STAT modes. The 905 model allows user-defined method scripting for KF and STAT; the 907 includes factory-loaded, validated methods.

Sample Compatibility & Compliance

The 905/907 series accommodates aqueous and non-aqueous matrices across pH 0–14, redox potentials from −2000 to +2000 mV, and temperature ranges of 0–100 °C (with Pt1000 or NTC probe integration). Ion-selective electrode (ISE) compatibility enables direct concentration calculation for F⁻, Cl⁻, NO₃⁻, NH₄⁺, and other analytes per ISO 10304 and ASTM D6508. All hardware and firmware components are designed to meet IEC 61326-1 (EMC) and IEC 61010-1 (safety) standards. When configured with tiamo™ in validated mode, the system satisfies FDA 21 CFR Part 11 requirements for electronic records and signatures, supports ALCOA+ data integrity principles, and aligns with ISO/IEC 17025 clause 7.7 on result reporting traceability.

Software & Data Management

tiamo™ serves as the central analytical platform—deployable as standalone desktop application or networked database server. It enables parallel titration sequence management, cross-instrument method synchronization, and centralized storage of raw sensor data, processed curves, and final reports in vendor-neutral formats (XML, CSV, PDF/A-2). Built-in evaluation algorithms support fixed endpoint, derivative (dE/dV), inflection point (for photometric/conductometric modes), pK determination (HNP algorithm), and custom polynomial fitting. All user actions—including method edits, sample assignments, and report exports—are logged with immutable timestamps and operator IDs. PCMCIA and USB interfaces allow secure offline backup of methods, calibration files, and encrypted user credentials.

Applications

These instruments are routinely deployed in pharmaceutical QC labs for assay validation (USP , EP 2.2.20), food & beverage testing (AOAC 975.37 for acidity, ISO 8536 for chloride), petrochemical analysis (ASTM D664 for TAN), environmental monitoring (EPA 300.0 for halides), and battery electrolyte R&D (Li-ion conductivity and impurity titration). The integrated Ipol/Upol polarizer module supports electroanalytical methods such as iodometric copper determination and cerimetric iron assays. KF functionality complies with ASTM E203 and ISO 760 for water content quantification down to 10 ppm in solvents, polymers, and active pharmaceutical ingredients.

FAQ

What distinguishes the 905 from the 907 model?
The 905 supports user-editable method development for KF volumetric and STAT titrations, while the 907 ships with pre-validated, factory-loaded methods for those techniques—optimized for labs prioritizing out-of-the-box compliance.
Is tiamo™ software included with purchase?
Yes—both models ship with a perpetual license for tiamo™ Standard Edition. Optional upgrades to Professional Edition (for advanced statistical analysis and LIMS integration) are available separately.
Can the system interface with third-party LIMS or ERP platforms?
Via LabLink and tiamo™’s ODBC-compliant database schema, the instrument supports bidirectional data exchange with common LIMS (e.g., Thermo Fisher SampleManager, LabWare LIMS) and enterprise systems using SQL-based connectors.
How is electrode performance verified under GLP conditions?
The Smart Electrode Test routine performs automatic slope, offset, and response time checks against configurable acceptance criteria, generating a timestamped GLP report with pass/fail status and corrective action prompts.
What safety certifications apply to the 905/907 hardware?
All units carry CE marking per EU Directive 2014/30/EU (EMC) and 2014/35/EU (LVD), and comply with UL 61010-1 and CSA C22.2 No. 61010-1 for North American markets.