Leichi SFK-506V Karl Fischer Volumetric Moisture Titrator

Overview

The Leichi SFK-506V Karl Fischer Volumetric Moisture Titrator is a fully automated, microprocessor-controlled analytical instrument engineered for precise and reproducible determination of water content in solid, liquid, and gaseous samples using the volumetric Karl Fischer (KF) titration principle. Based on the stoichiometric reaction between iodine and water in the presence of sulfur dioxide, pyridine (or modern amine-based buffers), and methanol, the system quantifies moisture by measuring the volume of standardized KF reagent consumed to reach the electrochemical endpoint—detected via bipotentiometric (dual-platinum electrode) polarization current monitoring. Designed for routine QC laboratories, pharmaceutical manufacturing units, and R&D facilities operating under regulated environments, the SFK-506V complies with core method validation requirements outlined in USP , EP 2.5.12, and ASTM E203. Its architecture supports both direct titration and coulometric-compatible sample introduction via integrated KF oven interface, enabling trace-level moisture analysis across diverse matrices without manual intervention.

Key Features

• 7-inch high-resolution color TFT touchscreen interface with intuitive graphical navigation and multi-language support (English/Chinese)
• Triple-tier user permission management (System Administrator, Lab Manager, Analyst) with password protection and audit trail logging
• Comprehensive GMP-compliant software suite featuring electronic signatures, operation history tracking, and full data traceability per FDA 21 CFR Part 11 Annex 11 expectations
• Integrated solvent management module with leak-proof reagent delivery, anti-siphon waste bottle design, automated rinsing cycles, and dual-path fluid handling (titrant addition + wash solution)
• Four operational modes: Standard KF titration, KF titer calibration, KF oven-assisted analysis (with programmable temperature ramping), and oven blank subtraction
• Real-time potentiometric monitoring with adjustable sensitivity (polarization current range: 1–200 µA), endpoint detection resolution of 0.1 mV, and drift compensation algorithms
• Flexible result reporting: units selectable among µg, mg, %, ppm, µg/L, and mg/L; PDF export capability; local print via RS-232 or USB; U-disk bulk data transfer

Sample Compatibility & Compliance

The SFK-506V accommodates a broad spectrum of sample types—including hygroscopic powders (e.g., APIs, excipients), viscous liquids (oils, solvents), and volatile gases—when coupled with its optional KF heating oven (not included). Sample introduction methods include direct syringe injection, oven purging, and balance-linked weighing (via USB-connected analytical balance). All measurement protocols adhere to Good Laboratory Practice (GLP) and Good Manufacturing Practice (GMP) frameworks. System-generated audit trails record user ID, timestamp, method parameters, raw titration curves, endpoint confirmation, and manual overrides—ensuring full compliance with regulatory data integrity standards. Calibration verification is supported through certified water standards (e.g., 1.00 mg/mL Hydranal® standard), and instrument performance checks meet ISO/IEC 17025 internal verification criteria.

Software & Data Management

Embedded firmware enables secure, role-based access to method libraries, sample logs, reagent lot tracking, sensor diagnostics, and maintenance scheduling. The system stores up to 2000 complete test records locally, each containing raw electrode signals, titration volume vs. time profiles, calculated moisture mass, statistical summaries (n=3 RSD), and operator annotations. Data export options include encrypted CSV for LIMS integration and formatted PDF reports compliant with ALCOA+ principles (Attributable, Legible, Contemporaneous, Original, Accurate, Complete, Consistent, Enduring, Available). Remote connectivity via WLAN allows centralized fleet monitoring and over-the-air software updates through Leichi’s authorized moisture control platform.

Applications

• Pharmaceutical quality control: residual moisture in lyophilized products, tablet granules, and sterile drug substances per ICH Q5C guidelines
• Chemical manufacturing: water content verification in catalysts, monomers, and high-purity solvents (e.g., acetonitrile, THF)
• Food & beverage testing: moisture quantification in dairy powders, spices, and dehydrated ingredients per AOAC 955.03
• Polymers & electronics: detection of trace moisture in lithium battery electrolytes and epoxy resins affecting curing kinetics
• Petroleum industry: water-in-fuel analysis per ASTM D6304 and D1744 standards

FAQ

What is the difference between volumetric and coulometric Karl Fischer titration?
Volumetric KF (used by SFK-506V) delivers standardized iodine-containing titrant from a burette; it is optimal for samples with water content >100 µg. Coulometric KF generates iodine electrochemically and is preferred for sub-10 µg measurements.
Does the SFK-506V support external balance integration?
Yes—via dedicated USB port, it synchronizes with Class I analytical balances (0.01 mg readability) for automatic sample weight import and % moisture calculation.
Can the instrument be validated for 21 CFR Part 11 compliance?
It provides foundational features (audit trail, electronic signatures, user permissions); final validation requires site-specific IQ/OQ/PQ protocols executed by qualified personnel.
Is oven drying functionality built-in or optional?
The SFK-506V includes oven control interface and communication protocol; the heating oven itself is an optional accessory (model-specific, sold separately).
How often should the KF electrodes be cleaned and calibrated?
Electrodes require cleaning after every 10–15 analyses using recommended solvent (e.g., methanol); calibration verification with standard water solution is advised before each batch of critical samples.