BFC-1 Centrifuge Tube Balancing Scale by AS ONE

Overview

The BFC-1 Centrifuge Tube Balancing Scale is a precision-engineered mechanical dual-pan balancing instrument developed by AS ONE Corporation (Japan) for rapid, visual weight matching of centrifuge tubes prior to rotor loading. Unlike electronic analytical balances, the BFC-1 operates on classical lever-arm equilibrium principles—eliminating dependency on power sources, calibration drift, or electromagnetic interference. Its design targets a critical pre-analytical step in centrifugation protocols: ensuring paired tube mass symmetry to within ±0.1 g tolerance, thereby minimizing rotor imbalance, vibration, and potential safety hazards during high-speed rotation (≥10,000 rpm). The scale is not intended for quantitative mass measurement but serves as a dedicated verification tool aligned with Good Laboratory Practice (GLP) requirements for centrifuge safety and reproducibility. Its compact footprint and passive operation make it suitable for placement directly adjacent to centrifuge workstations, biosafety cabinets, or cold rooms.

Key Features

• Mechanical dual-pan architecture with center-beam pointer and vernier-style visual equilibrium indicator—enabling immediate, operator-interpretable balance confirmation without digital readouts.
• Stainless steel (SUS304) weighing platform ensures corrosion resistance against common solvents (e.g., ethanol, acetone) and routine decontamination procedures.
• Dedicated PMMA centrifuge tube holder (Ø50 × 86 mm) with vertical alignment guides, optimized for standard conical-bottom polypropylene tubes (e.g., Eppendorf 5424/5430, Thermo Fisher 15–50 mL formats).
• PVC base stand provides stable, non-slip support on benchtops; integrated leveling screws allow fine-tuning on uneven surfaces—critical for consistent beam alignment across daily use.
• Open-top Ø36 mm insertion aperture accommodates tubes up to Ø35 mm diameter while permitting unobstructed visual inspection of liquid meniscus and tube labeling during balancing.
• Lightweight (820 g) yet rigid construction enables easy repositioning without compromising mechanical stability—validated per JIS B 7721-1 (Japanese Industrial Standard for mechanical balances).

Sample Compatibility & Compliance

The BFC-1 supports all common sterile and non-sterile centrifuge tubes meeting ISO 13485-compliant dimensional tolerances for conical-bottom formats. Compatible tube types include polypropylene (PP), polycarbonate (PC), and polyethylene (PE) vessels ranging from 0.5 mL microcentrifuge tubes to 50 mL conical tubes—provided outer diameter remains ≤35 mm. The scale does not accommodate swing-bucket adapters or sealed rotors; it is strictly intended for open-tube weight pairing prior to rotor insertion. While not certified under OIML R76 or NIST Handbook 44, its mechanical repeatability and traceable manufacturing origin (Japan) support compliance with internal quality control procedures referenced in ISO/IEC 17025:2017 Clause 6.4.3 (Equipment Verification) and CLSI EP10-A3 (Preliminary Evaluation of Quantitative Clinical Laboratory Measurement Procedures).

Software & Data Management

The BFC-1 is a fully analog, software-free instrument. It requires no firmware, drivers, or connectivity interfaces. All operational verification—including zero-point stability checks and sensitivity assessment—is performed manually using standardized test weights (e.g., Class M2 stainless steel reference masses) in accordance with ISO 9001:2015 Section 7.1.5. Documentation of daily balance verification may be recorded in paper-based lab notebooks or electronic quality management systems (QMS) such as LabVantage or Veeva Vault QMS, satisfying audit requirements for GLP/GMP environments where instrument traceability is mandated.

Applications

• Pre-centrifugation tube pairing in clinical diagnostics laboratories processing blood plasma, serum, or urine specimens.
• Biosafety Level 2 (BSL-2) cell culture workflows requiring balanced loading of cryovials into ultralow-temperature centrifuges.
• Academic research labs performing density gradient centrifugation (e.g., sucrose or Percoll gradients) where mass asymmetry induces band distortion.
• Pharmaceutical QC labs adhering to USP and guidelines for aseptic processing, where centrifuge safety is integral to environmental monitoring sample handling.
• Teaching laboratories introducing students to fundamental principles of mechanical equilibrium and pre-analytical error mitigation.

FAQ

Is the BFC-1 calibrated before shipment?
Yes—each unit undergoes factory verification using traceable reference masses at AS ONE’s Nagano production facility. A certificate of conformance (CoC) is included, referencing JIS Z 8000-2:2020 for verification methodology.
Can it be used with refrigerated or frozen tubes?
Yes—its all-mechanical design and non-electronic components ensure reliable operation at temperatures ranging from –20 °C to +40 °C, provided condensation is minimized on the beam mechanism.
Does it meet FDA 21 CFR Part 11 requirements?
No—Part 11 applies to electronic records and signatures. As a purely mechanical device generating no electronic data, the BFC-1 falls outside its scope; however, its use supports Part 11 compliance by enabling auditable, documented pre-centrifugation verification steps.
What maintenance is required?
Monthly visual inspection of beam pivot wear and quarterly cleaning of the SUS304 pan surface with isopropyl alcohol; no lubrication or recalibration is necessary under normal use conditions.
Is it compatible with rotor auto-balancing systems?
The BFC-1 complements—not replaces—modern centrifuges with dynamic imbalance detection. It reduces the frequency of auto-balancing interventions by ensuring optimal initial load symmetry, extending rotor bearing life and improving run-to-run consistency.