Sartorius ME5 Ultra-Micro Balance

Overview

The Sartorius ME5 Ultra-Micro Balance is an engineered solution for laboratories requiring trace-level mass determination under stringent regulatory and metrological conditions. Operating on electromagnetic force compensation (EMFC) principle, the ME5 delivers 0.001 mg readability across a 5.1 g capacity—enabling reliable quantification of sub-milligram samples in pharmaceutical development, reference standard preparation, catalyst dosing, and high-purity material characterization. Its design adheres to fundamental metrological requirements defined in OIML R 76 and EU Directive 2014/31/EU, while its performance validation framework supports compliance with USP repeatability criteria and USP minimum weight assessment (SQmin). The balance integrates isoCAL — Sartorius’ patented automatic internal calibration and adjustment system — which monitors temperature drift and initiates recalibration without user intervention, ensuring long-term stability and reducing manual calibration frequency in controlled environments.

Key Features

• Full-glass draft shield with conductive anti-static coating: Eliminates electrostatic interference on sample or container surfaces; provides unobstructed optical access to the weighing chamber.
• Tool-free, single-motion shield removal: Facilitates rapid cleaning and residue inspection—critical for GMP-regulated cleanroom workflows and cross-contamination prevention.
• Ergonomic actuation options: Motorized shield opening via front-panel button, foot switch, or remote PC command—minimizing operator-induced vibration during critical weighings.
• Graphical monochrome display with white LED backlight: High-contrast interface supporting multilingual prompts (English default); intuitive icon-driven navigation reduces training time and operational error.
• isoCAL technology: Continuous thermal monitoring triggers automatic internal calibration and linearization—maintaining accuracy across ambient fluctuations typical in QC labs.
• SQmin function: Real-time calculation and display of minimum sample weight per USP , integrating repeatability, readability, and user-defined confidence limits.
• 14 pre-programmed application methods: Including EUREKA for air buoyancy correction (per ISO 8655-6), micro-weighing with 999 customizable sample IDs, and statistical evaluation (mean, SD, RSD, min/max).

Sample Compatibility & Compliance

The ME5 accommodates standard Ø30 mm weighing pans and is compatible with low-profile crucibles, quartz micro-vials, and static-dissipative filter holders. Its full-glass enclosure supports visual verification of sample placement and residue detection—essential for method validation per ICH Q2(R2). The balance meets ISO/GLP data integrity requirements through timestamped, audit-trail-capable RS-232C output (bidirectional with printer or LIMS). When paired with Sartorius’ LabX software (optional), it satisfies FDA 21 CFR Part 11 electronic record and signature requirements—including role-based access control, electronic signatures, and immutable audit trails. All printed reports include instrument ID, calibration status, environmental parameters (if connected to optional sensors), and operator identification—fulfilling ALCOA+ principles.

Software & Data Management

Raw measurement data, calibration logs, and application-specific results are transmitted via RS-232C to external systems. The ME5 supports ASCII and Sartorius-specific protocols for seamless integration into laboratory informatics platforms. Optional LabX software enables centralized configuration management, automated report generation (PDF/CSV), and trend analysis of repeatability and linearity over time. Audit trail records capture every critical event—including weight recording, calibration initiation, parameter change, and user login/logout—with tamper-evident timestamps and operator attribution. Data export complies with ASTM E2500-21 for instrument qualification documentation.

Applications

The ME5 serves as a primary mass standard in regulated environments where uncertainty budgets must remain below 0.1% relative standard deviation. Typical use cases include: active pharmaceutical ingredient (API) assay standardization; gravimetric preparation of certified reference materials (CRMs); residual solvent quantification in lyophilized products; catalyst loading in asymmetric synthesis; and nanomaterial dispersion mass verification. Its fast stabilization (<10 s) and low drift rate make it suitable for dynamic processes such as real-time evaporation loss monitoring or humidity-controlled micro-weighing (when used inside environmental chambers).

FAQ

What is the minimum sample weight supported by the ME5 under USP ?
The SQmin function calculates and displays the minimum weight based on current repeatability (n=10), readability (0.001 mg), and user-defined confidence level (typically 95%). For typical lab conditions, this ranges between 1.0–2.5 mg.
Does the ME5 support external ionization for highly insulating samples?
Yes—optional external negative ionizers can be integrated to neutralize static charge on polymers, powders, or glassware, minimizing drift during prolonged measurements.
Can calibration certificates be generated directly from the balance?
While the ME5 does not store full calibration certificates internally, it outputs all required metadata (date/time, calibration mass value, deviation, temperature) via RS-232C for automated certificate generation in LabX or third-party QA systems.
Is the draft shield compatible with glovebox integration?
The full-glass, frameless design allows mechanical coupling to glovebox feedthroughs; however, custom mounting brackets and inert gas purge compatibility must be validated separately per ISO 14644-1 Class 5 environment specifications.