Agilent 7694 Headspace Sampler (Refurbished)

Overview

The Agilent 7694 Headspace Sampler (refurbished) is a fully automated, standalone static headspace sampling system engineered for precise, reproducible volatile compound introduction into gas chromatography (GC) instruments. It operates on the principle of phase equilibrium partitioning—where analytes in liquid or solid samples are thermally equilibrated in the sealed headspace above the sample matrix, followed by quantitative transfer of the vapor-phase aliquot via a pressurized loop injection mechanism. Designed and originally manufactured by Agilent Technologies in the United States, the 7694 integrates seamlessly with all major GC platforms—including Agilent, Thermo Fisher, Shimadzu, and PerkinElmer systems—via standardized carrier gas connections and RS232 serial interface. Its modular architecture enables rapid installation without GC hardware modification: only carrier gas supply and transfer line insertion into the GC inlet are required. The system supports method-driven temperature programming across all thermal zones (vial oven, valve manifold, transfer line), ensuring robust control over equilibration kinetics, vapor pressure dynamics, and injection integrity.

Key Features

• Fully automated 44-position vial carousel with programmable heating and optional agitation (SOFT/FAST modes) to enhance mass transfer and improve extraction efficiency for semi-volatile or viscous matrices.
• Independent thermal control of three critical zones: vial oven (15–220 °C), valve manifold (15–220 °C), and transfer tube (15–220 °C), each with ±1 °C accuracy and ±0.5 °C stability over time.
• High-inertness nickel sample loops available in 0.5 mL, 1 mL, and 3 mL volumes—optimized for sensitivity, dynamic range, and compatibility with trace-level analysis per USP , ICH Q3C, and EPA Method 502.2.
• Integrated digital pressure monitoring for both carrier and auxiliary gases, supporting method validation under GLP/GMP environments with audit-ready pressure logs.
• Onboard microprocessor (8-bit) with intuitive front-panel keypad (START, RESET, LOCK, SET, ACT, UP/DOWN) and 16-character LED display for real-time status feedback (WAIT, READY, AUTOSTART, RUN, LOCK).
• Comprehensive self-diagnostic suite verifying RAM/ROM integrity, heater probe functionality, valve actuation timing, transfer line temperature, and gas pressure sensors prior to each run sequence.

Sample Compatibility & Compliance

The Agilent 7694 accommodates standard 10 mL and 20 mL crimp-top vials fabricated from neutral borosilicate glass, sealed with PTFE-faced butyl or silicone septa. Its 6-position heated incubation stack allows staggered pre-equilibration—enabling continuous batch processing without downtime between runs. The system meets essential regulatory requirements for pharmaceutical residual solvent testing (USP , EP 2.4.24), environmental VOC analysis (EPA 502.2, 8240), and food safety screening (AOAC 992.17). All thermal and pneumatic parameters are logged with timestamped metadata, supporting compliance with FDA 21 CFR Part 11 when paired with compliant LIMS or CDS software. Traceable calibration records and refurbishment documentation—including functional verification against original Agilent specifications—are provided with each unit.

Software & Data Management

While the 7694 operates autonomously via front-panel programming, it supports bidirectional RS232 communication for remote method upload, run initiation, and status polling from external chromatography data systems (CDS). BCD-coded vial position output enables unambiguous sample tracking in multi-batch workflows. When integrated with Agilent OpenLab CDS or third-party platforms such as Chromeleon or Empower, the sampler contributes full audit trails—including valve timing events, temperature setpoints, pressure readings, and error codes—to electronic laboratory notebooks (ELN). All firmware versions are compatible with legacy Agilent ChemStation configurations, ensuring long-term method portability and operational continuity.

Applications

• Pharmaceutical quality control: Residual solvents in APIs and finished dosage forms (e.g., acetone, dichloromethane, ethanol).
• Environmental analysis: Volatile organic compounds (VOCs) in groundwater, soil extracts, and wastewater per EPA SW-846 methods.
• Food and beverage testing: Ethanol quantification, flavor compound profiling, and contaminant screening (e.g., benzene, chloroform).
• Polymers and packaging: Extractables and leachables assessment in plastic containers and medical device materials.
• Forensic toxicology: Blood alcohol concentration (BAC) determination and volatile drug metabolite detection.

FAQ

Is the Agilent 7694 compatible with non-Agilent GC systems?
Yes—the 7694 connects to any GC via standard 1/16″ stainless steel transfer tubing and carrier gas supply; no proprietary interface hardware is required.
What maintenance is recommended for long-term reliability?
Routine replacement of vial septa, periodic cleaning of the needle probe and valve seat, and annual verification of thermal accuracy using NIST-traceable reference standards are advised.
Does the refurbished unit include calibration certification?
Each unit ships with a full functional test report and temperature/pressure calibration verification performed against Agilent’s original factory specifications.
Can the 7694 perform dynamic headspace or purge-and-trap sampling?
No—it is strictly a static headspace system; dynamic sampling requires dedicated purge-and-trap instrumentation such as the Agilent 7667A.
What power configurations are supported?
Dual-voltage operation: 220 V ±10%, 50 Hz or 110 V ±10%, 60 Hz, both at 600 VA maximum draw.