Burrell Model 95 Variable-Speed Wrist Action Shaker

Overview

The Burrell Model 95 Variable-Speed Wrist Action Shaker is an engineered solution for applications requiring gentle, orbital-like agitation that closely replicates the biomechanical motion of manual wrist swirling. Unlike conventional rotary or reciprocating shakers, the Model 95 employs a true wrist-action mechanism—based on a pivoting arm assembly—that generates a controlled, low-shear oscillatory motion with a continuously adjustable arc (0–15°). This motion produces laminar fluid displacement ideal for cell suspension, tissue dissociation, immunoassay plate washing, gel staining/destaining, and hybridization protocols where sample integrity and mixing uniformity are critical. Designed and manufactured in the United States, the unit operates at ambient temperature only and is optimized for consistent performance across diverse life science workflows without thermal regulation.

Key Features

• True wrist-action kinematics: Patented oscillating arm delivers a smooth, non-turbulent swirling motion—distinct from orbital or linear shakers—minimizing foam formation and shear stress on sensitive biological samples.
• Variable speed control: Precision potentiometer enables stepless adjustment from 0 to 450 oscillations per minute (opm), supporting method development and protocol standardization across assay types.
• Dual-platform architecture: Two independently accessible shaking surfaces accommodate simultaneous processing of heterogeneous vessel sets—e.g., microtiter plates on one platform and Erlenmeyer flasks on the other—enhancing throughput without cross-contamination risk.
• Programmable timer: Built-in digital timer supports timed runs from 1 to 60 minutes or indefinite continuous operation; auto-shutoff ensures reproducible endpoint control and energy efficiency.
• Modular Build-Up System: Compatible with Burrell’s standardized accessory ecosystem—including Top Platforms, Side Arms, and Finger-SUREGRIP clamps—enabling scalable expansion from basic shaking to high-capacity multi-vessel configurations.
• Robust mechanical construction: Housing fabricated from powder-coated steel and aluminum alloy components ensures long-term stability, vibration damping, and resistance to laboratory solvents and cleaning agents.

Sample Compatibility & Compliance

The Model 95 accommodates a broad range of standard laboratory vessels via interchangeable SUREGRIP clamps and platform inserts. Verified compatibility includes up to ten 125 mL, eight 250–300 mL, or six 500 mL Erlenmeyer flasks; separatory funnels; glass or plastic specimen jars; and microplate carriers. All mounting hardware conforms to ANSI/ISO dimensional standards for universal fitment. The device is CE certified per Directive 2014/30/EU (EMC) and 2014/35/EU (LVD), ensuring electromagnetic compatibility and electrical safety in regulated laboratory environments. While not equipped with environmental chamber integration, its ambient-only operation aligns with CLSI EP25-A and ISO 15197:2013 requirements for non-temperature-critical mixing steps in clinical and research assays.

Software & Data Management

The Model 95 is a stand-alone electromechanical instrument with no embedded firmware, network interface, or data logging capability. Its analog speed and timer controls provide deterministic, repeatable operation without software dependencies—ideal for GLP/GMP environments where audit trails and validation of electronic records are subject to strict regulatory scrutiny (e.g., FDA 21 CFR Part 11). For laboratories requiring traceability, external documentation of setpoints (speed, duration, amplitude) and operational logs may be maintained manually or integrated into LIMS via barcode-scanned run sheets. No proprietary drivers or cloud connectivity are required, eliminating cybersecurity concerns associated with IoT-enabled instrumentation.

Applications

• Cell culture maintenance: Gentle resuspension of adherent and suspension cell lines during passaging and harvesting.
• Molecular biology: DNA/RNA probe hybridization in sealed bags or trays; blot membrane incubation with antibodies or detection reagents.
• Clinical diagnostics: Uniform mixing of whole blood samples prior to centrifugation; ELISA plate washing and substrate incubation.
• Histology & pathology: Gel electrophoresis staining/destaining (Coomassie, silver); tissue section antigen retrieval in buffer solutions.
• Quality control: Homogenization of reference standards and calibration materials in pharmaceutical QC labs compliant with USP and .
• Environmental microbiology: Extraction and elution of microbial cells from filters and solid-phase matrices.

FAQ

What distinguishes “wrist action” from orbital or reciprocating shaking?
Wrist action uses a single-axis pivot arm to generate a circular arc motion (0–15°), mimicking human wrist movement. This yields lower peak acceleration and more uniform fluid vortexing than orbital (horizontal circle) or reciprocating (back-and-forth) mechanisms—reducing bubble formation and cellular damage.
Can the Model 95 be used under a biosafety cabinet?
Yes. Its low acoustic noise (<55 dB(A)) and absence of heat-generating components allow safe placement inside Class II A2 cabinets when configured with non-aerosolizing vessel lids and appropriate airflow clearance.
Is the oscillation frequency calibrated and traceable to NIST standards?
The unit features a factory-calibrated analog tachometer with ±3% full-scale accuracy. Optional third-party calibration services (e.g., ISO/IEC 17025-accredited labs) can provide NIST-traceable verification reports upon request.
Does it support FDA 21 CFR Part 11 compliance?
As a non-computerized device with no electronic data generation, the Model 95 inherently satisfies Part 11 requirements for “systems without electronic records.” Validation focuses on mechanical consistency, timer accuracy, and amplitude repeatability—documented via IQ/OQ protocols.
How is load imbalance compensated during operation?
The dual-platform design incorporates independent counterbalance weights and precision-machined pivot bearings. Under maximum rated load (10 lb), measured vibration amplitude remains ≤0.05 mm RMS at all speeds—verified per ISO 10816-1 for laboratory equipment.