SSI Series II High-Pressure Solvent Delivery Pump

Overview

The SSI Series II High-Pressure Solvent Delivery Pump is an engineered solution for precise, stable, and maintenance-efficient liquid delivery in analytical and semi-preparative chromatographic systems. Based on a single-piston positive displacement architecture, it operates on stepper motor-driven actuation to deliver consistent volumetric flow across wide pressure gradients—up to 6000 psi with 316 stainless steel fluidic paths or 5000 psi with chemically inert PEEK construction. Its design centers on minimizing flow pulsation through an integrated low-dead-volume pulsation dampener and rapid fill technology, enabling near-continuous flow profiles critical for baseline stability in UV, fluorescence, and mass spectrometric detection. Unlike multi-piston or dual-piston configurations, the Series II achieves pulse-free performance without complex synchronization mechanisms—relying instead on mechanical optimization and real-time solvent-assisted piston seal conditioning.

Key Features

• Three selectable flow ranges: 0.001–5 mL/min, 0.01–10 mL/min, and 0.1–40 mL/min—each calibrated and validated for linearity and repeatability.
• On-column, solvent-driven auto-cleaning system positioned immediately downstream of the piston seal; activated by normal pump operation to flush particulate and precipitate buildup using mobile phase—reducing seal wear and extending service intervals.
• Tool-free piston seal replacement in under five minutes, enabled by modular seal carrier design and standardized O-ring geometry.
• One-touch priming, degassing, and solvent exchange functionality—supporting both automated purge/fill cycles and manual syringe-assisted evacuation.
• Digital RS232 interface for remote control, parameter logging, and integration into centralized lab automation frameworks compliant with ASTM E1384 and ISO/IEC 17025 data integrity requirements.
• Internal bypass valve, pulse dampener, and pressure relief assembly—all factory-assembled and pre-validated for leak-tight operation at maximum rated pressure.

Sample Compatibility & Compliance

The Series II accommodates a broad spectrum of mobile phases—from aggressive organic solvents (acetonitrile, THF, chloroform) to high-salt aqueous buffers and corrosive acids/bases—depending on selected wetted materials. PEEK fluidic paths meet USP Class VI biocompatibility standards and are suitable for protein purification, oligonucleotide synthesis, and metal-sensitive applications where leaching must be eliminated. Stainless steel variants conform to ASTM A276 and EN 10088-3 specifications for corrosion resistance in HPLC-grade environments. All models support GLP/GMP workflows via audit-trail-capable software interfaces and comply with pressure vessel safety guidelines per PED 2014/68/EU when operated within specified limits.

Software & Data Management

While the Series II operates as a standalone instrument with front-panel keypad and LED display, its RS232 port enables bidirectional communication with third-party chromatography data systems (CDS), including Thermo Chromeleon, Waters Empower, and Agilent OpenLab. Firmware supports command-set protocols aligned with ANSI X3.27–1994 for serial instrumentation control. Logged parameters—including actual flow rate, backpressure, elapsed runtime, and auto-clean cycle timestamps—are timestamped and exportable in CSV format. When integrated into regulated environments, the pump’s digital control loop satisfies FDA 21 CFR Part 11 requirements for electronic records when paired with validated CDS platforms featuring user authentication, electronic signatures, and immutable audit trails.

Applications

• Analytical-scale reversed-phase, ion-exchange, and size-exclusion chromatography (SEC/GPC) requiring sub-1% RSD flow stability over 24-hour runs.
• Semi-preparative purification of natural products, peptides, and synthetic intermediates at flow rates up to 40 mL/min and pressures exceeding 4000 psi.
• Method development labs needing rapid solvent switching between orthogonal gradient methods without manual line flushing or air bubble entrapment.
• Quality control laboratories performing compendial assays per USP , EP 2.2.46, or JP 6.01, where pump accuracy and inter-instrument reproducibility are subject to routine verification.
• Academic research setups integrating custom-built detectors or microfluidic interfaces demanding low-dead-volume, low-pulsation flow sources.

FAQ

What flow ranges are available—and how are they selected?
The Series II offers three factory-configured flow modules: 0.001–5 mL/min (for nano/micro-LC), 0.01–10 mL/min (standard analytical LC), and 0.1–40 mL/min (semi-prep). Range selection is hardware-defined via piston diameter and stroke length; users must specify required range at time of order.
Is PEEK construction compatible with 100% TFA or HFIP?
PEEK demonstrates excellent resistance to trifluoroacetic acid (TFA) below 50°C and short-term exposure to hexafluoroisopropanol (HFIP); however, prolonged use above 60°C or in >20% HFIP concentrations may accelerate hydrolytic degradation—consult SSI Chemical Compatibility Guide before deployment.
How often does the auto-cleaning solution require replacement?
The reservoir for the solvent-driven cleaning loop should be refilled weekly with deionized water or a mild aqueous buffer; no consumables beyond the reservoir fluid are required for standard operation.
Can the Series II replace older SSI models without hardware modification?
Yes—the Series II maintains identical mounting footprint, electrical connector pinout, and fluidic port locations as Series I and earlier SSI pumps, enabling drop-in replacement in legacy HPLC systems without adapter kits or plumbing rework.
Does the pump support gradient mixing?
No—the Series II is a single-channel solvent delivery device. Gradient formation requires external low-pressure or high-pressure mixing modules (e.g., SSI GP-100 or compatible third-party quaternary modules) connected upstream or in-series configuration.