Ultramicropump III by World Precision Instruments (WPI)

Overview

The Ultramicropump III is a high-precision, digitally controlled syringe pump system engineered for ultra-low-volume fluid delivery in electrophysiology, microinjection, patch-clamp, and neurophysiological applications. Operating on a stepper-motor-driven linear actuation principle, it delivers exceptional volumetric resolution—600 picoliters (pL) per motor step when paired with a standard 5 mL glass syringe. This level of precision enables reproducible intracellular, intranuclear, or extracellular microinjections in live tissue preparations, brain slices, oocytes, and embryonic models. The pump’s direct-drive mechanism eliminates backlash and slippage, ensuring consistent displacement without dead volume accumulation—critical for quantitative pharmacological dosing and tracer delivery where residual air gaps or syringe compressibility would compromise experimental fidelity.

Key Features

• Picovolume resolution: 600 pL per step with 5 mL syringes; scalable resolution via syringe selection and step subdivision
• Zero-dead-volume operation: Full forward injection or reverse aspiration with no residual air gap or syringe barrel compression artifacts
• Modular mechanical integration: Compatible with WPI mounting platforms including the M3301 micromanipulator base, DC3001 digital controller stand, and stereotaxic frames (e.g., Model 940)
• Universal syringe compatibility: Accepts glass or plastic syringes with barrel diameters from 5.5 mm to 9.0 mm—no adapter required
• Single-controller multi-pump coordination: SYS-MICRO4 controller manages up to four Ultramicropump III units simultaneously, enabling synchronized perfusion/aspiration protocols
• Intuitive LCD interface: Real-time display of mode (infuse/withdraw), target volume, flow rate, syringe type, and pump status
• Parameter memory retention: User-defined protocols—including volume, speed, direction, and syringe calibration—are stored non-volatilely and recalled instantly at power-on

Sample Compatibility & Compliance

The Ultramicropump III supports a wide range of biocompatible syringes—including borosilicate glass (e.g., Drummond NanoFil®, Hamilton 10 µL–1 mL series) and polypropylene disposable units—enabling sterile, pyrogen-free delivery in GLP-compliant electrophysiology labs. Its mechanical design conforms to IEC 61000-6-2 (immunity) and IEC 61000-6-3 (emission) standards for laboratory equipment. While not FDA-cleared as a medical device, the system is routinely deployed in preclinical research environments operating under AAALAC-accredited animal care programs and adhering to NIH Guide for Care and Use of Laboratory Animals. Calibration traceability follows NIST-traceable volumetric standards using gravimetric verification methods per ASTM E2758.

Software & Data Management

The SYS-MICRO4 controller operates independently without PC dependency but supports optional RS-232 serial communication for external automation via LabVIEW, MATLAB, or Python-based control scripts. All parameter changes—including start/stop commands, volume updates, and directional toggles—are logged with timestamps in internal memory. Audit trails are exportable as CSV files for regulatory documentation. Though not compliant with 21 CFR Part 11 out-of-the-box, the system can be integrated into validated workflows when paired with third-party electronic lab notebook (ELN) platforms supporting user authentication, electronic signatures, and change-controlled protocol storage.

Applications

• Intracellular microinjection of dyes (e.g., Alexa Fluor® conjugates), caged compounds (e.g., NP-EGTA), or CRISPR-Cas9 ribonucleoprotein complexes into neurons and glia
• Pressure- and flow-controlled perfusion during whole-cell patch-clamp recordings to maintain stable drug concentration gradients
• Controlled aspiration of cytoplasmic contents during single-cell transcriptomic sampling
• Delivery of viral vectors (AAV, lentivirus) into discrete brain regions in stereotaxic rodent surgery
• Dynamic fluid exchange in organotypic slice cultures to study synaptic plasticity or metabolic response kinetics

FAQ

What syringe sizes are supported?
Syringes with barrel diameters between 5.5 mm and 9.0 mm are mechanically compatible—including 10 µL, 50 µL, 100 µL, 250 µL, 500 µL, and 5 mL calibrated glass syringes.
Can the Ultramicropump III perform bidirectional flow control?
Yes—each unit supports both infuse and withdraw modes with identical resolution and repeatability, enabling reversible fluid exchange in closed-loop experimental designs.
Is calibration required before each experiment?
Initial syringe-type calibration is performed once per syringe model and retained in memory; recalibration is only necessary if switching syringe brands or after mechanical maintenance.
How is synchronization achieved across multiple pumps?
The SYS-MICRO4 controller issues synchronized TTL-compatible trigger signals to all connected pumps, ensuring sub-millisecond timing alignment for multi-channel perfusion or dual-injection paradigms.
Does the system support continuous infusion at ultra-low flow rates?
Yes—flow rates down to 0.1 nL/min are achievable with appropriate syringe selection and step-rate configuration, maintaining linearity and stability over extended durations (>24 h).