Lowest LOQs - The unparalleled high resolution capabilities of the DFS provide the highest specificity for trace and target compound analysis for unambiguous compound identification and deliver superior signal to noise characteristics for reliable peak integration and quantitation.

• Ease of operation - The DFS is operated like and feels like a benchtop GC/MS. The automated universal mass calibration is unique and provides the full versatility for all scan modes and ionization techniques.
• Highest sample throughput - The DFS offers your lab unattended automatic operation with full method versatility.
• Two GCs can be optionally installed in parallel for maximum flexibility on column separations. Thermo Scientifc TriPlus™ XT
• Autosampler serves both GCs from common sample trays.

DFS Mass Spectrometer

The DFS is a high resolution magnetic sector mass spectrometer like none before.

Several new technologies have been incorporated in this revolutionary design. All of these combined provide the most powerful high resolution GC/MS ever. The DFS high resolution GC/MS operates under Thermo Scientific Xcalibur™, the premier data system, for complete system control and automated data processing.

DFS High Resolution GC/MS

High Performance Magnetic Sector GC/MS

Thermo Scientific DFS High Resolution GC/MS is the highest performance magnetic sector mass spectrometer ever built for target compound analysis. The DFS is as simple and straightforward in operation as your benchtop MS systems.

Ion Source

The ion source has been designed with special emphasis on sensitivity and durability for increased productivity, low maintenance and increased uptime.

• Plug-in ion source with 1 push operation
• Exchange of ion volume and filament without venting by a pneumatically actuated vacuum interlock
• Response optimized EI volume with special filament, optimized box design for quick exchange including built in ion extraction lens for ease of maintenance
• Optimized long lifetime filaments for EI and CI
• Each ionization volume carries its own special filament for the ionization technique
• One ion source for all techniques EI, CI (PCI/NCI)
• GC interface control independent of source temperature

Reference Inlet

The independent reference compound inlet system is continuously flow adjustable and can be individually evacuated. It allows syringe introduction of liquid or gaseous samples.

Vacuum Interlock

The DFS is equipped with a vacuum interlock for quick exchange of ionization volumes and filaments without venting.

• Pneumatically actuated
• Faulty operation is virtually eliminated by system control

Tuning

The DSF enables the reliable, routine use of AUTOTUNE in all ionization modes without restrictions, including slit control and automated reso-lution setting. All tuning lenses are part of the ion source.

The DFS provides TunePlus™, the renowned user interface for Thermo Scientific ion trap, quadrupole GC/MS and LC/MS instruments. For the first time, a magnetic sector mass spectrometer uses the same concept, making tuning, experiment and sequence set-up intuitive and simple. High resolution MID is an integral part of this user interface.

Mass Calibration

Thermo Fisher Scientific invented the field calibration method of scanning magnetic mass spectrometers. The DFS offers full data system control of field calibration scanning. The mass scale needs to be calibrated only once. The operator can change mass range and scan speed without the need for recalibration. It is the same approach and handling as known from benchtop GC/MS systems.

• Constant mass calibration based on magnetic field measurement
• Calibration independent of mass range, scan speed, scan mode (including linked scan MS/MS), ion polarity and ionization technique
• No recalibration required after change of ion volume or ionization technique

Analyzer

The newly designed DFS analyzer is the first with virtually no image aberrations. It is perfectly double focusing, employing an ultra high precision toroidal electrostatic analyzer and a carefully refined magnetic analyzer. This directly translates into stability and ruggedness.

• Novel ion optics design is based on the proven reverse Nier-Johnson geometry
• Mass independent focus with uniform resolution throughout the mass range
• Ion optics optimized for an acceleration voltage of 5 kV
• All ionization techniques operational with full acceleration voltage
• High precision, data system controlled, continuously variable Tantalum entrance and exit slits for fast response and long lifetime
• Low hysteresis, radially laminated H-type magnet of special metal alloy with mass independent focal length, deflection radius 350 mm, deflection angle 65°
• Innovative Rogowsky magnet entrance pole pieces for optimum sensitivity regardless of ionization method
• Novel electrostatic analyzer (ESA) using a computer optimized toroidal design for highest mass precision and ion transmission with virtually no image errors
• All focusing and detection elements housed in a single monoblock vacuum chamber
• Entire DFS analyzer assembled on an integrated shock mounted platform for isolation from floor vibration

Performance Characteristics

• Resolution (static) > 60,000 (10% valley)
• Scan rates 0.1 to 10,000 seconds/decade (continuously variable)
• Mass accuracy < 2 ppm
• Sensitivity EI GC/MS S/N > 800:1 for 100 fg 2378 TCDD at m/z 322, R = 10,000
• Mass range 2 - 6000 Da; 2 - 1200 Da at full acc. voltage

Detection System

The long lifetime secondary electron multiplier of the DFS always provides optimal signal amplification for all ionization modes including negative CI.

• Long lifetime off axis secondary electron multiplier detection system
• Post-acceleration/conversion dynode, variable to ± 20 kV (Thermo Fisher Scientific patent)
• Quick change mount on an individual flange

Vacuum System

The clean high vacuum background produced by turbomolecular pumps enables the DFS to achieve lower detection limits routinely.

• Directly coupled high speed differential pumping system with three turbo molecular pumps
• Push-button control
• Automated protection system

Electronics Cabinet

Integrated electronics cabinet for low space requirements. Optimized air flow for efficient cooling of magnet power supply. Effective potential decoupling between digital electronics and mass spectrometer high voltage and power supplies.

• Universal input/output for Ready/Start communication with external devices using programmable signal logic
• Analog in
• Digital in/out

Direct Inlet Options

Direct Probe Base Unit (optional)

• Port for direct insertion probe
• Required to attach any of the following probe options
• Contains exchange lock and probe electronics

Water Cooled DI Probe (DI / DIP) (optional)

• Direct insertion probe
• Data system controlled, liquid cooled
• Using disposable aluminum crucibles
• Heating rates: 20 °C to 200 °C in 30 s, 200 °C to 300 °C in 30 s
• Temperature range from 10 °C above ambient
• Maximum temperature 350 °C

DCI Probe (optional)

• Direct chemical ionization probe
• Full data system control
• Using reusable filaments
• Ultra fast heating rates of > 500 °C/s
• Maximum temperature 1600 °C
• High temperature tip for DCI probe (optional)
• Using reusable quartz crucibles
• Maximum temperature 800 °C

Software Specifications

Xcalibur Data System

Xcalibur is the uniform software platform for system control of the Thermo Scientific GC/MS and LC/MS systems. The DFS comprises the complete Xcalibur instrument control software package for high and low resolution operation, multiple ion detection MID, selection of positive or negative ions, linked scans, peak matching, and full control of analyzer and inlet systems supporting the following capabilities:

• INTENSITY AUTOTUNE independent from resolution
• RESOLUTION AUTOTUNE with computer controlled slit setting
• Control of standard and optional inlet systems
• Xcalibur accurate mass program CMASS for accurate mass conversion and averaging
• Complete Xcalibur application software, incorporating all mass spectrometry processing tasks such as chromatogram and spectrum display, integrated NIST library search, elemental composition and isotopic pattern calculation
• QuanBrowser, the comprehensive quantification package
• Instrument diagnostics
• MS data import and export using the ANDI/netCDF formats, conversion from Finnigan MassLab data file formats, ASCII text export
• Standardized output to LIMS systems

TargetQuan (optional)

The special Xcalibur DFS software package for automated data evaluation on target compounds including:

• Dioxin method setup
• Support of instrument and quantitation
• Response file and reporting programs
• Data evaluation for isotope dilution methods as well as relative response factors
• Compliant with the published EPA methods for dioxin measurements and data evaluation according e.g. EPA 1613, EPA 8280, EPA 8290, EPA 23, EPA 513, EN 1948 and equivalent JIS methods
• Compliant with the requirement for TEQ low-med-upper bound reporting
• Standardized output to LIMS systems

Library Options

• NIST Library
• Wiley Library
• Pfleger-Maurer-Weber Library
• Thermo Scientific Pesticide Library

Software Licenses

The DFS Xcalibur software licenses are supplied for instrument control as well as reprocessing. New instrument software releases are supplied free of charge within 12 month after delivery.