Peiou SKD-1100 Fully Automated Kjeldahl Nitrogen Determinator

Overview

The Peiou SKD-1100 Fully Automated Kjeldahl Nitrogen Determinator is an engineered solution for precise, high-throughput total nitrogen and protein quantification in accordance with ISO 8968, AOAC 981.10, AOAC 984.13, ASTM D1193, and USP . Based on the classical Kjeldahl digestion–distillation–titration principle, the system automates the complete analytical workflow—from acid digestion (performed off-instrument using standard Kjeldahl digesters), through alkaline distillation and condensate collection, to endpoint detection via photometric colorimetric titration. The instrument implements a robust, closed-loop fluidic architecture with corrosion-resistant PTFE and borosilicate glass components, ensuring long-term operational integrity in aggressive acidic and alkaline environments typical of routine nitrogen analysis.

Key Features

• Fully integrated automation: Sequential execution of alkali addition, boric acid reagent dosing, steam distillation, condensate transfer, colorimetric titration, system rinsing, and data archiving—without manual intervention.
• High-fidelity endpoint detection: Dual-wavelength optical sensor monitors bromocresol green–methyl red indicator color transition (pH 4.5–5.2) during titration, eliminating subjective visual interpretation and enhancing inter-operator reproducibility.
• Optimized thermal management: Independently controlled steam generator and condenser maintain consistent distillation kinetics across sample matrices, minimizing carryover and ensuring stable 3–5 minute cycle times per sample.
• Intuitive human-machine interface: 7-inch full-color capacitive touchscreen with multilingual GUI (English, Spanish, German, Chinese), configurable method templates, and real-time status visualization—including reagent levels, temperature profiles, and titration curves.
• Compliance-ready architecture: Built-in audit trail, user access control (three-tier permission levels), electronic signature support, and data export in CSV and PDF formats—aligned with GLP, GMP, and FDA 21 CFR Part 11 requirements for regulated laboratories.

Sample Compatibility & Compliance

The SKD-1100 accommodates diverse solid and liquid matrices within the defined mass range (0.1–5 g solids; up to 20 mL liquids), including cereal grains, dairy powders, animal feed, soil extracts, wastewater sludge digests, and chemical intermediates. Its validated recovery rate of ≥99.5% meets the acceptance criteria specified in ISO 5983-1 and AOAC Official Method 991.20. All wetted materials comply with USP Class VI biocompatibility standards, and the system supports method validation per ICH Q2(R2) guidelines. Regulatory documentation—including Factory Acceptance Test (FAT) reports, IQ/OQ protocols, and calibration certificates traceable to NIST standards—is provided upon installation.

Software & Data Management

The embedded firmware supports method-driven operation with up to 99 customizable programs, each storing parameters for digestion time (external), NaOH concentration, boric acid volume, distillation duration, titrant strength, and reporting units (N%, protein%, or absolute mg N). Raw titration data—including absorbance vs. volume curves and equivalence point calculations—is retained locally with timestamped metadata. Export options include encrypted USB transfer and network-based FTP/SFTP upload to LIMS or ELN systems. Software updates are delivered via secure HTTPS channel with SHA-256 signature verification.

Applications

This instrument serves as a primary nitrogen quantification platform in QC/QA labs across food & beverage (e.g., compliance with Codex Alimentarius Standard 206 for protein labeling), agricultural testing (fertilizer N-content verification per ISO 5315), environmental monitoring (total Kjeldahl nitrogen in municipal effluents per EPA Method 351.2), and pharmaceutical excipient characterization (nitrogen impurity profiling per ICH Q3D). It is routinely deployed in accredited laboratories holding ISO/IEC 17025:2017 certification for elemental analysis.

FAQ

What digestion equipment is required for use with the SKD-1100?
The SKD-1100 performs only distillation and titration; digestion must be conducted separately using a certified Kjeldahl digester (e.g., block heater or microwave system) meeting ISO 8968-1 specifications.
Can the instrument be integrated into an existing LIMS environment?
Yes—via standardized ASTM E1384-compliant ASCII text output or optional OPC UA server module for real-time bidirectional communication.
Is method validation support available from Peiou?
Peiou provides application notes, validation templates aligned with ISO/IEC 17025, and on-site technical assistance for IQ/OQ/PQ execution upon request.
What maintenance intervals are recommended for optimal performance?
Daily: Rinse cycle verification and waste tank inspection. Quarterly: Calibration of titrant pump and optical sensor; annual: Steam generator descaling and gasket replacement per maintenance log.
Does the system meet regulatory requirements for pharmaceutical testing?
When operated under documented SOPs with qualified reagents and calibrated glassware, the SKD-1100 satisfies USP , EP 2.5.21, and JP 17 nitrogen determination requirements for drug substance and product release testing.