METTLER TOLEDO ET08 Karl Fischer Moisture Analyzer

Overview

The METTLER TOLEDO ET08 Karl Fischer Moisture Analyzer is a dual-mode (coulometric and volumetric) titration system engineered for precise, trace-level to high-concentration water quantification across diverse sample matrices. It operates on the electrochemical principle of the Karl Fischer reaction—where iodine generated in situ (coulometric mode) or delivered via standardized titrant (volumetric mode) stoichiometrically reacts with water in anhydrous methanol-based electrolyte. The endpoint is detected potentiometrically using a dual-platinum polarized electrode pair, monitoring the abrupt shift in polarization current (0–50 µA range, ±0.1 µA resolution) as free water is consumed. Designed for routine QC laboratories and R&D environments, the ET08 delivers robust reproducibility (≤0.5% RSD under controlled conditions) and compliance-ready operation without requiring advanced analytical training.

Key Features

• Dual-method flexibility: Switch seamlessly between coulometric (for samples with <1% water, down to 100 ppm detection limit) and volumetric (for higher water content up to 100%) modes via intuitive touchscreen navigation.
• iTitrate intelligent method setup: Guides users through parameter configuration—including titrant concentration, sample weight, solvent volume, and endpoint criteria—minimizing operator dependency and method transfer errors.
• Integrated hardware design: Includes a dedicated KF magnetic stirrer base (0.8 kg), lightweight weighing boat with integrated sealing cap, liquid-sampling septum adapter, and desiccated air purge system to maintain anhydrous titration conditions.
• High-fidelity electrochemical detection: Dual-platinum BNC electrode (EM43-BNC) ensures stable polarization current measurement with low-noise signal acquisition across the full 0–2000 mV input range.
• Modular connectivity: Supports direct data export and remote control via USB-A (printer, flash drive) and USB-B (PC communication); compatible with METTLER TOLEDO EasyDirect™ Titration software for audit-trail-enabled reporting.

Sample Compatibility & Compliance

The ET08 accommodates solids, liquids, pastes, and gases—ranging from pharmaceutical excipients and polymer granules to lubricating oils and solvents—without modification to core hardware. Its sealed titration cell architecture, combined with the included drying tube (30044701) and air pump (30064218), prevents ambient moisture ingress during analysis. Method validation aligns with pharmacopeial standards including USP , EP 2.5.12, and ASTM E203. When operated with EasyDirect™ Titration software and configured with electronic signatures, audit trails, and user access controls, the system supports 21 CFR Part 11 compliance for regulated environments. All firmware and calibration routines are traceable to METTLER TOLEDO’s Swiss manufacturing quality system (ISO 9001 certified).

Software & Data Management

Data integrity is enforced through native USB-driven integration with EasyDirect™ Titration software, enabling automated calculation, report generation (PDF/CSV), and long-term archiving with time-stamped metadata. The software provides full GLP/GMP support: user-defined roles and permissions, electronic signatures, instrument calibration logs, and full audit trail functionality—including record creation, modification, and deletion events. No manual transcription is required: results, titration curves, and raw sensor outputs (polarization current vs. time/volume) are captured automatically. For standalone use, the 4.3-inch resistive touchscreen displays real-time titration progress, endpoint confirmation, and statistical summaries (mean, SD, RSD) directly on-device.

Applications

• Pharmaceuticals: Quantification of residual moisture in APIs and lyophilized products per ICH Q5C guidelines.
• Chemicals & Polymers: Monitoring water content in monomers, catalysts, and engineering resins where hydrolysis sensitivity dictates strict specifications.
• Foods & Beverages: Validation of low-moisture stability in powdered dairy, spices, and dehydrated ingredients.
• Electronics: Verification of moisture levels in battery electrolytes and encapsulation materials to prevent dendrite formation.
• Petroleum & Lubricants: Detection of trace water in transformer oils and hydraulic fluids per ASTM D6304.

FAQ

What is the difference between coulometric and volumetric Karl Fischer titration on the ET08?
Coulometric mode generates iodine electrochemically within the titration cell—ideal for samples containing ≤1% water and offering superior precision at trace levels (100 ppm detection limit). Volumetric mode dispenses pre-standardized KF reagent from a 10 mL EasyPlus burette—suited for higher water concentrations (up to 100%) and heterogeneous or viscous samples.
Does the ET08 meet regulatory requirements for GMP laboratories?
Yes—when paired with EasyDirect™ Titration software and configured with appropriate user access controls, electronic signatures, and audit trail settings, the ET08 satisfies FDA 21 CFR Part 11, EU Annex 11, and ISO/IEC 17025 documentation requirements.
Can the ET08 be used for gas-phase moisture analysis?
Yes—using the optional gas sampling kit (not included in standard configuration), the system supports headspace injection of vapor-phase samples into the KF cell, enabling determination of moisture in compressed air, nitrogen blankets, or process gases.
Is calibration traceable to national standards?
All factory calibrations are performed using NIST-traceable water standards (e.g., sodium tartrate dihydrate, disodium tartrate dihydrate) and documented in the instrument’s calibration certificate, which accompanies each unit shipped from METTLER TOLEDO’s facility in Greifensee, Switzerland.
How is electrode maintenance handled?
The EM43-BNC dual-platinum electrode requires periodic cleaning with ethanol and light polishing; its performance is verified using a 1.0 mg water standard. The ET08’s built-in electrode diagnostics monitor polarization stability and alert users if drift exceeds predefined thresholds.