Metrohm 905 Titrando Automatic Potentiometric Titrator
| Brand | Metrohm |
|---|---|
| Origin | Switzerland |
| Manufacturer | Metrohm AG |
| Type | 905 Titrando |
| Measurement Range | ±1200 mV, ±120 µA |
| Accuracy (Burette) | 0.15% (±30 µL at 20 mL) |
| Resolution | 0.001 pH, 0.1 mV, 0.1 °C |
| Titration Modes | DET, MET, SET, KF Coulometric & Volumetric, STAT |
| Compliance | FDA 21 CFR Part 11, GLP/GMP, ISO/IEC 17025 applicable |
Overview
The Metrohm 905 Titrando is a high-precision, modular automatic potentiometric titrator engineered for reproducible, traceable, and fully compliant quantitative chemical analysis in regulated laboratory environments. Operating 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 delivers robust electrochemical quantification across acid-base, redox, precipitation, and complexometric reactions. Its architecture integrates real-time voltage/pH/current monitoring with programmable titration algorithms (DET, MET, SET), enabling rigorous stoichiometric determination without operator-dependent interpretation. Designed for routine QC, R&D, and regulatory submissions, the 905 Titrando meets the metrological demands of pharmaceutical, food, environmental, and petrochemical laboratories requiring audit-ready data integrity.
Key Features
- Patented Dosino™ dosing units mounted directly atop reagent bottles—eliminating benchtop footprint and minimizing dead volume, air entrapment, and cross-contamination risk.
- Transparent dosing unit housing enables visual verification of bubble presence and valve actuation status; automated priming, rinsing, and purging require no manual disassembly.
- Modular expansion capability: supports up to two 800 Dosino modules (each accommodating two 807 burettes), four 801 magnetic stirrers, or four 804 titration stands with 802 rod stirrers—or dedicated 803 KF titration stations.
- Digital Smart Cable interface ensures noise-immune transmission of measurement signals; Smart Electrodes auto-identify type, calibration history, and serial number upon connection.
- Integrated Ipol/Upol programmable polarizer for controlled potential applications (e.g., amperometric titrations); optional differential amplifier for low-signal electrochemical measurements.
- 90 mm × 120 mm color touchscreen with 100 ms measurement interval; simultaneous display of real-time titration curve, derivative plot, and numeric readouts (pH/mV/°C/current).
Sample Compatibility & Compliance
The 905 Titrando accommodates aqueous and non-aqueous matrices—including viscous oils, suspensions, and organic solvents—via interchangeable electrode configurations (glass pH, Ag/AgCl, Pt, ion-selective, redox, and KF-specific electrodes). It supports sample introduction via manual vial placement or integration with Metrohm’s 863 Compact Sample Processor or 864 Autosampler. All hardware and firmware comply with ISO/IEC 17025:2017 requirements for testing laboratories. Data acquisition, user authentication, electronic signatures, audit trails, and method version control conform strictly to FDA 21 CFR Part 11 and EU Annex 11 guidelines. GLP-compliant electrode diagnostics—including drift rate assessment, response time validation, and slope verification—are embedded within the tiamo™ software suite.
Software & Data Management
Controlled via tiamo™ 3.x (Windows-based), the system provides centralized method development, database management, and multi-instrument network operation. tiamo™ supports relational database architecture for long-term storage of methods, raw data, processed results, metadata (operator ID, timestamp, instrument ID), and electronic signatures. Parallel titration workflows—where multiple samples undergo identical protocols simultaneously—are natively supported. LabLink connectivity enables secure LAN/WAN access for remote monitoring, data export (CSV, PDF, XML), and integration into LIMS or ERP systems. PC Control mode permits direct instrument operation from third-party software environments. All data files are digitally signed and tamper-evident; backup is enabled via PCMCIA card slot supporting encrypted flash memory.
Applications
- Pharmaceuticals: USP and EP 2.2.20-compliant assay of active ingredients (e.g., chlorides in antibiotics, citric acid in effervescent tablets).
- Food & Beverage: AOAC 944.13-compliant salt (NaCl) determination, acidity (titratable acidity) in dairy and fruit juices, SO₂ in wine.
- Environmental: EPA Method 300.0 and ISO 9297-compliant chloride/bromide analysis in wastewater; cyanide speciation by ligand displacement titration.
- Chemical Industry: ASTM D664 acid number in lubricants; base number (ASTM D974) in transformer oils; Karl Fischer water content (volumetric and coulometric modes).
- Materials Science: Quantification of free fatty acids in biodiesel (EN 14104); residual catalyst metals in polymerization processes.
FAQ
Does the 905 Titrando support both volumetric and coulometric Karl Fischer titration?
Yes—when equipped with the 851 KF Coulometer module and compatible KF reagents, the system executes both volumetric (via Dosino burette) and coulometric (via generator electrode) water determination per ASTM E203 and ISO 760 standards.
Can tiamo™ manage user permissions across multiple instruments in a shared lab environment?
Yes—tiamo™ implements role-based access control (RBAC) with hierarchical user groups, customizable privilege sets (e.g., “Method Editor”, “Data Reviewer”, “System Administrator”), and mandatory electronic signatures for critical actions.
Is temperature compensation automated during pH and redox titrations?
Yes—integrated Pt1000 or NTC temperature probes feed real-time thermal data to the evaluation engine, enabling automatic activity correction in pH calculations and Nernst equation adjustments in redox endpoints.
What is the maximum number of titration steps permitted in a single user-defined method?
Methods support unlimited sequential steps—including pre-titration conditioning, multi-stage additions, pause intervals, conditional branching (IF/THEN logic), and post-titration electrode cleaning cycles—programmable via tiamo™’s graphical method editor.
How is data integrity verified during long-term archival?
All raw data (.TDF binary files) include embedded cryptographic hashes; tiamo™ generates SHA-256 checksums at acquisition and validates them upon file open or export—ensuring detectability of any unauthorized modification.
