OHAUS MB23 Infrared Moisture Analyzer | MB25 | MB35 | MB45 Halogen Rapid Moisture Analyzer

Overview

The OHAUS MB23, MB25, MB35, and MB45 Moisture Analyzers are precision laboratory instruments engineered for rapid, gravimetric determination of moisture content in solid and semi-solid samples using thermogravimetric analysis (TGA). These analyzers operate on the principle of controlled heating followed by real-time mass loss monitoring—where moisture is volatilized under defined thermal conditions, and the resulting weight change is converted into a quantitative moisture percentage. The MB23 and MB25 models employ infrared heating elements optimized for gentle, uniform thermal exposure—ideal for heat-sensitive or sugar-rich matrices prone to caramelization or surface charring. In contrast, the MB35 and MB45 utilize high-intensity halogen lamps, delivering faster ramp rates and finer temperature resolution (1 °C steps up to 200 °C), enabling accelerated drying cycles without compromising measurement integrity. All four models integrate analytical balance technology with programmable thermal profiles, endpoint detection logic, and GLP-ready data handling—making them suitable for routine QC testing, raw material verification, and R&D applications across food, pharmaceutical, chemical, and materials science laboratories.

Key Features

• Gravimetric moisture determination compliant with ASTM D4442, ISO 712, and AOAC 952.08 methodologies
• Dual-sensor architecture: high-resolution load cell (0.001 g readability on MB35/MB45) synchronized with calibrated thermal control system
• Four distinct heating programs: Standard, Rapid, Gentle, and Step (MB35/MB45 only) — configurable per sample type to optimize drying kinetics and prevent decomposition
• GLP-compliant reporting: automatic timestamping, user ID entry, method recall, and audit-trail-capable RS232 output for integration with LIMS or electronic lab notebooks
• Backlit monochrome LCD (128 × 64 pixels) with multi-parameter display: % moisture, % solids, current weight, elapsed time, chamber temperature, and optional drying curve visualization (MB35/MB45)
• Rugged die-cast aluminum housing with 90 mm stainless-steel weighing pan and ergonomic sample-handling handle
• Temperature stability ≤ ±1 °C over full operating range (10–40 °C ambient); humidity tolerance ≤ 80% RH non-condensing

Sample Compatibility & Compliance

The MB series accommodates diverse sample types—including powders, granules, pastes, films, and hygroscopic solids—with recommended sample masses between 0.5 g and 20 g. The MB23/MB25’s infrared source minimizes radiant hotspots, reducing risk of localized overheating in sucrose-rich foods (e.g., confectionery, dairy powders) or thermolabile botanical extracts. The MB35/MB45’s halogen system supports rapid dehydration of low-moisture ceramics, polymers, and pharmaceutical excipients where throughput and repeatability are critical. All units meet CE marking requirements and support regulatory workflows aligned with FDA 21 CFR Part 11 (when paired with validated printer and software), USP , and ISO/IEC 17025 documentation standards. Built-in calibration verification routines and drift compensation algorithms ensure long-term metrological reliability without external service intervention.

Software & Data Management

Data export is facilitated via bidirectional RS232 interface, supporting direct transmission to PCs running OHAUS Logger Pro™ or third-party SCADA/LIMS platforms. Each measurement record includes method ID, operator code, start/end timestamps, final moisture value, standard deviation across replicate runs, and full drying curve metadata (weight vs. time at 10-second intervals on MB35/MB45). Print outputs include header fields for lab name, instrument ID, and QA approval signature lines—fully traceable for internal audits or external inspections. Firmware supports password-protected method libraries, user-level access control (administrator/operator), and automatic firmware update notifications via connected host systems.

Applications

• Food & Agriculture: moisture validation in flour, coffee beans, spices, pet food, and feed pellets per AOAC protocols
• Pharmaceuticals: residual solvent quantification in active pharmaceutical ingredients (APIs), excipient dryness testing pre-blending, and lyophilized product residual moisture assessment
• Chemicals & Polymers: water content verification in catalysts, silica gels, PVC resins, and epoxy curing agents
• Building Materials: moisture analysis in gypsum board, wood composites, and insulation foams per ASTM C561 and EN 1323
• Academic Research: kinetic modeling of drying behavior, sorption isotherm generation, and thermal degradation onset studies

FAQ

What is the difference between infrared and halogen heating in OHAUS moisture analyzers?
Infrared heating (MB23/MB25) provides broad-spectrum, lower-intensity radiation ideal for delicate or sugar-laden samples that degrade above 160 °C. Halogen heating (MB35/MB45) delivers focused, high-power output enabling precise 1 °C temperature control up to 200 °C—suited for refractory or low-moisture materials requiring aggressive drying.
Can the MB45 be used for moisture testing in compliance with USP <921>?
Yes—the MB45 supports method validation per USP <921> through programmable endpoint criteria (e.g., weight change ≤ 0.1 mg/30 s), temperature ramp profiling, and GLP-compliant data capture including operator ID, calibration status, and environmental logs.
Is calibration traceable to NIST standards?
OHAUS moisture analyzers ship with factory calibration certificates traceable to NIST-traceable mass standards; users may perform internal verification using certified reference weights and moisture standards (e.g., sodium tartrate dihydrate, 15.66% H₂O).
What maintenance is required to sustain accuracy over time?
Routine cleaning of the heating chamber and weighing pan with lint-free cloth and isopropyl alcohol is recommended after each use. Annual verification of thermal uniformity and balance linearity is advised; no consumables or lamp replacements are required during normal operation.
Does the MB35 support automated drying curve export?
Yes—via RS232, the MB35 transmits time-weight-temperature triplets at user-defined intervals (default: 30 s), enabling post-acquisition kinetic analysis in Excel or MATLAB.