Truelab BM-400 Stomacher-type Homogenizer

Overview

The Truelab BM-400 Stomacher-type Homogenizer is a precision-engineered laboratory instrument designed for the mechanical homogenization of solid and semi-solid samples in sterile, single-use bags. Operating on the principle of controlled reciprocal percussion—commonly referred to as “stomaching”—the device subjects samples to rhythmic, high-frequency compressive impacts between two parallel plates, facilitating efficient cell lysis, microbial release, and uniform suspension formation without thermal degradation or cross-contamination. This method is widely recognized in international microbiological standards—including ISO 6887-1, ASTM D5600, and USP <61>—as a validated approach for sample preparation prior to enumeration, isolation, or molecular analysis. The BM-400 is engineered for reproducibility, operator safety, and compliance with Good Laboratory Practice (GLP) requirements, making it suitable for routine use in food safety laboratories, pharmaceutical QC/QA departments, clinical diagnostics, and academic research settings.

Key Features

• Digital microprocessor control with large backlit LCD display for real-time monitoring of time, speed, stroke, and (on BM-400HP) temperature
• Stainless steel housing (grade 304) ensures corrosion resistance, structural rigidity, and ease of decontamination
• Adjustable pulsing frequency (3.0–12.0 cycles/sec) and stroke length (0–40 mm) enable optimization across diverse sample matrices—from soft tissues and dairy products to fibrous plant material and freeze-dried powders
• Full-opening front door with ergonomic design facilitates rapid insertion and removal of sample bags and simplifies interior cleaning
• Tempered glass viewing window allows visual verification of homogenization progress without interrupting operation
• Integrated safety interlock system automatically halts motion when the door is opened, preventing accidental contact during operation
• Dedicated waste collection tray beneath the chamber captures minor bag leakage, minimizing biohazard exposure and simplifying spill response
• UV-C sterilization module (254 nm, 5 min cycle) available on BM-400P and BM-400HP models, supporting routine chamber disinfection between runs
• For BM-400HP: Peltier-based temperature regulation (ambient to 50 °C) maintains consistent thermal conditions during extended homogenization—critical for heat-sensitive analytes or controlled lysis protocols

Sample Compatibility & Compliance

The BM-400 accommodates standard ISO-compliant stomacher bags (typically 400 mL capacity), including pre-sterilized, low-binding, and DNA/RNA-stabilizing variants. It supports homogenization of food commodities (meat, fish, produce, baked goods), environmental swabs, clinical specimens (fecal, wound, respiratory), pharmaceutical tablets and ointments, and cosmetic emulsions. All operational parameters—including timer resolution (0.1 min), speed granularity (0.1 cycle/sec), and programmable protocols—are traceable and auditable, aligning with FDA 21 CFR Part 11 data integrity expectations when paired with compliant laboratory information management systems (LIMS). The device meets CE marking requirements for electrical safety (EN 61010-1) and electromagnetic compatibility (EN 61326-1).

Software & Data Management

While the BM-400 operates via embedded firmware without external PC dependency, its 10-program memory enables secure storage of standardized methods—including those required by AOAC Official Methods of Analysis® or ISO/IEC 17025-accredited workflows. Each protocol retains independent settings for duration, frequency, stroke, and (where applicable) temperature setpoint. Audit trails are maintained internally via timestamped parameter logs accessible through service mode. For integration into regulated environments, optional RS-232 or USB-to-serial interfaces support automated logging into LIMS or ELN platforms—ensuring full traceability from sample receipt to analytical result.

Applications

• Microbial enumeration (aerobic plate count, coliforms, Listeria, Salmonella) per ISO 6887, FDA BAM, and APHA guidelines
• Preparation of homogenates for PCR, qPCR, and next-generation sequencing (NGS) workflows in foodborne pathogen detection
• Extraction of antigens, toxins, or allergens from complex matrices for immunoassay analysis
• Homogenization of pharmacopeial dosage forms (e.g., tablets, capsules, creams) for content uniformity testing per USP <905>
• Standardized tissue disruption in veterinary and clinical pathology labs
• Environmental sampling—soil, water filters, and air collection media—prior to culture or molecular screening

FAQ

What sample bag sizes are compatible with the BM-400?
The BM-400 is optimized for standard 400 mL stomacher bags (e.g., 80 × 120 mm or 115 × 170 mm formats); smaller volumes (down to 10 mL) may be processed using appropriately sized bags with sufficient liquid phase to ensure effective impact transmission.
Is the BM-400 suitable for sterile processing under ISO Class 5 conditions?
While the instrument itself is not classified as a cleanroom-grade device, its sealed chamber design, UV-C sterilization option, and compatibility with gamma-irradiated bags support aseptic workflow integration when operated within appropriate environmental controls.
Can the BM-400 be validated for GMP use?
Yes—the device supports IQ/OQ documentation packages, including calibration of timer accuracy (±0.1 sec), speed verification (via tachometer), and temperature uniformity mapping (for BM-400HP). Full validation support materials are available upon request from Truelab’s technical services team.
Does the BM-400 require routine maintenance beyond cleaning?
No consumable parts are involved in the drive mechanism; recommended preventive maintenance includes quarterly inspection of door gasket integrity, verification of UV lamp output intensity, and lubrication of stroke guide rails per manufacturer’s service manual.
How does the BM-400 compare to rotary-blade homogenizers for microbial recovery?
Stomacher-type homogenization provides superior recovery of surface- and intracellular-bound microorganisms from heterogeneous solids—particularly foods—by avoiding shear-induced cell lysis artifacts common in blade-based systems, thereby improving assay accuracy and reproducibility.