Metrohm 890 Titrando Volumetric Karl Fischer Moisture Analyzer

Overview

The Metrohm 890 Titrando is a high-precision volumetric Karl Fischer (KF) moisture analyzer engineered for trace- to full-range water quantification in pharmaceuticals, chemicals, polymers, petrochemicals, and food matrices. It operates on the stoichiometric iodine-based redox reaction defined by the Karl Fischer method—where water reacts quantitatively with iodine, sulfur dioxide, and a base in methanol or alternative solvents. In volumetric mode, the instrument delivers standardized KF reagent via a precision burette; water content is calculated from the titrant volume consumed, corrected for reagent titer and sample mass. Unlike coulometric systems optimized for sub-100 ppm analysis, the 890 Titrando excels across the full dynamic range of 10 ppm to 100% w/w water—making it suitable for hygroscopic solids, viscous oils, gaseous samples (via gas sampling valve), and heterogeneous slurries.

Key Features

• Fully automated titration sequence with real-time endpoint detection using bipotentiometric (dual-platinum) electrode system and adaptive slope evaluation
• Intelligent dosing unit with digital chip embedded in each burette—automatically registers volume capacity (1, 5, 10, 20, or 50 mL), resolution (1/20,000), reagent name, concentration, titer, expiry date, and usage history
• Integrated membrane pump for solvent replenishment and waste evacuation—eliminates manual handling and ensures consistent cell environment
• Safety Stop function: halts titration upon abnormal current drift, over-titration, or electrode contamination—preventing erroneous results and reagent waste
• Hermetically sealed titration vessel with optimized PTFE-coated stirrer and low-drift sealing architecture—typical background drift < 5 µg H₂O/min under standard lab conditions
• Modular hardware design supporting optional 803 KF titration stand, 862 Compact Titrosampler, or 867 pH Meter integration via MSB interface

Sample Compatibility & Compliance

The 890 Titrando accommodates diverse physical states without modification: liquids (e.g., solvents, monomers), solids (tablets, powders, resins), pastes (greases, adhesives), and gases (compressed air, SF₆, natural gas). Sample introduction is compatible with oven couplers (for thermally released water), dry gas purging, and direct injection. Regulatory alignment includes full adherence to ISO 8533:2017 (Karl Fischer titration), ASTM E203–22, USP “Water Determination”, European Pharmacopoeia 2.5.12, and Japanese Pharmacopoeia 2.07. Its electronic record architecture satisfies FDA 21 CFR Part 11 requirements—including user access controls, electronic signatures, immutable audit trails, and data integrity validation protocols required for GxP environments.

Software & Data Management

Operation is supported by two complementary platforms: the onboard 7-inch color touchscreen with intuitive graphical interface and offline method editing capability; and tiamo™ software (v3.4+), a validated PC-based application for centralized laboratory management. tiamo™ enables concurrent control of up to 16 instruments, parallel titration scheduling, and synchronized data acquisition. Its relational database supports unlimited storage (subject to host HDD capacity), advanced filtering (by date, operator, method, batch ID), statistical reporting (RSD, recovery %, linearity checks), and customizable PDF/CSV export. All raw data—including titration curves, electrode potential vs. time, and reagent consumption logs—are retained with timestamped metadata and version-controlled method files.

Applications

• Pharmaceutical QC: Residual moisture in lyophilized APIs, tablet coatings, and excipients per ICH Q5C stability guidelines
• Chemical manufacturing: Water content verification in catalysts, silicone fluids, and epoxy resins prior to polymerization
• Energy sector: Moisture monitoring in transformer oils (IEC 60814), biodiesel (EN 14103), and LNG feedstocks
• Food & beverage: Quantification of free water in dairy powders, chocolate, and dehydrated vegetables per AOAC 992.18
• Electronics: Detection of adsorbed moisture in PCB laminates and semiconductor packaging materials affecting dielectric performance

FAQ

What distinguishes volumetric from coulometric Karl Fischer titration?
Volumetric KF measures water by consuming a standardized iodine-containing titrant; it is optimal for samples containing >100 ppm water. Coulometric KF generates iodine electrochemically at the anode and is preferred for ultra-trace analysis (<100 ppm). The 890 Titrando operates exclusively in volumetric mode.
Can the 890 Titrando be integrated into a LIMS environment?
Yes—via native Ethernet (TCP/IP) or USB-to-serial gateway, it transmits structured result data (ASTM E1384-compliant) directly to LIMS, ELN, or SAP QM modules with configurable field mapping.
Is tiamo™ software validated for regulated laboratories?
tiamo™ is supplied with IQ/OQ documentation packages and supports installation qualification, operational qualification, and periodic performance verification per GAMP 5 guidelines.
How does the Safety Stop function enhance analytical reliability?
It monitors real-time current deviation, endpoint overshoot, and electrode polarization anomalies—triggering automatic pause and alert generation before invalid titrations compromise data integrity or consume excess reagent.
What maintenance routines are recommended for long-term accuracy?
Daily: Electrode cleaning with methanol, cell drying, and drift check. Weekly: Burette calibration verification using certified water standards (e.g., Hydranal® 1.00 mg H₂O/mL). Annually: Full system performance qualification per Metrohm PQ protocol.