Since its invention, there has been extensive R&D work ongoing toward improving mass analysis technology, as is the case with any other high-tech field. To date, mass spectrometry technologies have gained incredible technological advances. Nowadays, various kinds of mass spectrometers are in use for mass analysis. Among the most widely used mass analyzers are ion trap, quadrupole, time of flight, quadrupole ion trap, and others. Here, we will discuss the time of flight mass spectrometer detailing its technology, advantages, and application. So, our focus will be to present a thorough review of TOF MS in which we will elaborate on various aspects of Markes TOF MS.
GC TOF MS is the short form of Gas Chromatography Time of Flight Mass Spectrometry and is a variant of GCMS systems. A GC separates different analytes within a chemical compound by eluting it through a column. The TOFMS acts as a detector to detect ions of the analytes eluted by the GC.
A TOFMS identifies ions by calculating their Time-of-Flight at a fixed distance. The mechanical layout of a TOFMS system is simple compared to other types of mass spectrometers allowing a TOFMS to be extremely fast in electronic signal acquisition. As analyte molecules exit the column of the GC, they enter the analyzer chamber of the TOFMS and become ionized. Then the ions are accelerated toward the detector by an electric energy (E) of a specific magnitude. The resultant velocity of an ion will be according to its mass-to-charge ratio (m/z). Measuring the time (t) an ion takes to travel a fixed distance (s) establishes its travel velocity (v). Once E and v are known, the mathematical formula m = 2*E/v2 determines the mass of an ion. A Rapid TOF-MS detection capability makes TOFMS the most demanding mass analysis technology.
Some core capabilities of commonly available time of flight mass spec systems may include the following:
- Mass range: up to 480000 au
- Mass resolutions: > 10500
- Ion optical transmission efficiency: > 10%
- The flight path of the flight tube: 1000 to 2000 mm
- Kinetic energies: up to 2000 eV
- Flight times: 5 to 100 µs
- Peak widths: 500-700 picoseconds
BenchTOF is the trademark of Markes International Ltd. and SepSolve Analytical, UK. Markes and SepSolve are leaders in manufacturing high-tech laboratory instruments like mass spectrometry, thermal desorber, multimode sampling system, etc. BenchTOF2 time-of-flight mass spectrometer is the latest edition of the state-of-the-art BenchTOF series TOF MS systems developed and manufactured by SepSolve. The BenchTOF2 mass spectrometer has the following specifications and capabilities.
The BenchTOF2 Time-of-Flight (TOF) MS is designed to enable laboratories to meet evolving analytical challenges and growing workloads with increased data accuracy while keeping costs low. BenchTOF2 is highly competitive in performing all TOF mass spectrometer functions like
- Simultaneous analysis of the complete ion list
- Yielding full mass spectra for unknown and selected compounds in one run
- Optimized sensitivity
Traditional mass spectrometers suffer from poor sensitivity and ion wastage. Though the Selected Ion Monitoring (SIM) mode provides better sensitivity, it can't analyze unknown compounds.
Benefits of BenchTOF2
- Trusted identification of analyte thru an unrivaled fusion of exceptional selectivity, SIM grade sensitivity, intelligent software suit, and high-resolution spectra.
- Upgraded detection limits can detect vast trace-level compounds in a single run in full spectral details with the advantage of a look-back search for new species.
- Five-degree magnitude broad dynamic range allows precise quantification of a high-density species without compromising on low detection capacity, eliminating the need to run again or dilution.
- Patented Tandem Ionisation® technology permits the simultaneous acquisition of hard and soft EI spectra in individual runs aiding in the correct identification of complex compounds like isomers in a simple process.
- High-speed data acquisitions allow BenchTOF2 MS to assist in faster GC and GC×GC separations.
- Enhanced productivity by H2 carrier gas compliance, speedy chromatographic separation, quicker investment return, low ownership cost, and smooth new lab setup.
- The graphical user interface incorporates system control, method setup & optimization, data processing, and chemo-metrics in one platform that is helpful to non-MS experts to self-learn with less training.
GCTOFMS Specifications
Time of Flight MS Technical Data
- Ionization mode: Electron ionization (EI), 70 eV
- Electron energy: 1-180 eV
- Mass range: m/z 10–1000.
- Linear dynamic range of TOF MS: 5 orders of magnitude
- Mass resolution (70 eV): >1250 Full Width at Half Maximum (FWHM) over 100–1000 m/z
- Mass accuracy: <0.0001 absolute
- Mass stability: <0.10 m/z over 30 days.
- Time resolution: 0.8 ns, with continuum spectra recorded to 0.008 amu resolution.
- Scan rate: 14,500 u/sec
- Flight path length: 2.5m
- Tuning: Auto
- Carrier gas: Helium, Purge gas: Nitrogen/Argon
- Ion source temperature: 100 to 400 °C
- Transfer line temperature: 50 to 450 °C
- Detector: Extended-life continuous dynode electron multiplier (CEM)
- Detector sampling rate: Up to 150 Gbits/sec
- Maximum recommended carrier gas flow rate: 10 mL/min
- Pumping System: Two stage, differentially pumped source and analyzer chambers. 260 L/s split-flow turbomolecular pump (TMP) with 2.5 m3/hr roughing pump
- Vacuum Measurement: Integrated digital transmitter with continuous pressure measurement from 10e2 to 10e-11 mbar.
- System equilibration time: 25 min from full system vent
- Data acquisition speed: Up to 600 full-range spectra (to m/z 1000) saved into disk per second.
- Native spectral acquisition rate: 12,000 Hz.
- Data conversion speed: 1.1 GHz
- EI Sensitivity at 70 eV: 1 pg of Octafluoronaphthalene (OFN) (m/z 272.0) gives a signal-to-noise ratio (S/N) >2200:1 RMS while acquiring full spectra up to m/z 1000.
- Instrument detection limit (IDL): IDL <50 fg OFN.
- GC Interface: Integrates with Agilent/Thermo Fisher/Perkin Elmer/Shimadzu/SCOIN and other GCs
- Software: Instrument control, data acquisition and processing, data analysis, reporting
- Mass Spectral Libraries: NIST, Wiley, MassBank, SWGDRUG
- Power Requirements: 230 V AC, 50 Hz, 450VA
- Regulatory certifications: CE, ISO 9001.
GC Technical Data
- Simultaneously operate two injectors, three detectors, three detector signals
- Cutting-edge electronics
- Electronic Pneumatics Control (EPC) for all injectors and detectors
- Precision control of pressure set point down to 0.001 psi
- Four mode column flow control
- Atmospheric pressure and temperature fluctuation offset
- Automatic liquid sampling, gas sampling
- Option for gas sampling valve, column switching valve
- Display all GC and ALS setpoints on front panel
- Set point, automation control from local keyboard or thru networked data system
- Clock time programming for timed events
- Column oven can accommodate up to two columns
- Oven temperature controllable from ambient + 5°C to 450°C
- Temperature set point resolution: 0.1°C
- Ambient rejection should be <0.01 °C
- Maximum 22 ramps with 23 plateaus in oven temperature programming. Negative ramps accepted.
- Maximum achievable oven temperature ramp rate: 125°C/min
- Oven cool down from 450°C to 50°C in 4 mins.
- Maximum run time: 999.99 mins
- Split/Splitless inlet with inert flow path
- Split ratio up to 7000:1
- Maximum inlet temperature: 400°C
- Electronic control of inlet flow and septum purge flow
- EPC pressure control resolution of ±0.001 psi for the entire range of 0 to 150 psi
- Pressure setpoint resolution 0.001 psi
- Gas saver mode
- EPC automatically compensates ambient temperature and barometric pressure change
- EPC supports maximum three flow/pressure ramps
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