The Vocus PTR-TOF offers unmatched sensitivity and mass resolving power for online detection of VOCs

A proton transfer reaction mass spectrometer (PTR-MS) with sub-ppt limits of detection and mass resolving power up to 15000

Announcing Improved Vocus PTR-TOF Performance and a New Model for Online VOC Monitoring

Advantages of the Vocus PTR-TOF

The Vocus PTR-TOF is a proton transfer reaction mass spectrometer (PTR-MS) for sensitive, real-time detection of volatile organic compounds (VOCs) in industrial, laboratory, and field applications.

  • Ultra-Low Limits of Detection.  High sensitivity and low backgrounds combine to yield sub-ppt VOC limits of detection in seconds
  • Highest Available Mass Resolving Power.  Mass resolving power up to 15000 enables identification of isobaric compounds in complex mixtures
  • Mobile Measurement. Compact, durable architecture brings laboratory-grade performance to vehicle and aircraft-based measurements
  • Adaptable for Your Applications. Work with us to integrate the Vocus PTR-TOF into your existing sampling systems and workflows
  • Intuitive, Powerful Software. Easy-to-use data acquisition interface and Tofware graphical post-processing software for the analysis of high-resolution TOF data
  • Revolutionary PTR Reaction Cell Design.  The proprietary Vocus reaction cell reduces wall losses and focuses ions to give you up to 10x the sensitivity of other commercial PTR-MS. Learn more about the Vocus technology

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Webinar: Vocus PTR-TOF Real-time VOC Analysis with Market Leading Performance


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Improving PTR-MS without Compromise

The unique Vocus ion molecule reactor (IMR) improves almost all aspects of PTR-MS performance, while maintaining critical specifications and reaction processes that have been established for conventional designs.  

These fundamental aspects of Vocus PTR-TOF performance are key to its fast, ultra-sensitive measurement of trace VOCs.

Select a Vocus Model to Meet Your Measurement Needs

  Sensitivity cps/ppb xylene Limit of Detection (LOD) 1-min / 1-s, xylene Resolving Power at  Specified Sensitivitya M/ΔM Maximum Resolving Powera M/ΔM Size Power Max / Typical
2R 30001 1 ppt  / 10 ppt  10000 15000 160 kg < 0.45 m3 480 x 615 x 1480 mm 600 / 590 W
30001 1 ppt  / 10 ppt 5000 7000  120 kg < 0.35 m3 480 x 615 x 1130 mm 600 / 590 W
Scout 4000  5 ppt, 1 min 3500 4000  120 kg < 0.35 m3 480 x 615 x 1130 mm 600 / 590 W
Elf 500 20 ppt, 1 min 500 750  55 kg < 0.125 m3 380 x 500 x 650 mm 450 /400 W

a. Each model can be operated with higher resolving power at reduced sensitivity.

Components

Standard

  • Standby Valve.  Allows servicing of Vocus reaction cell hardware without venting (Models 2R, S, and Scout).
  • Tofware Data Post Processing.
  • Library of Detectable Compounds.
  • Thuner Software. Automatic mass spectrometer tuning software.
  • Touch Screen Control.
  • Shipping Container.  Deployment with no disassembly required.
  • Acquility Data Acquisition and Instrument Control Software.
    • Automated gas calibration and zeroing with programmable cycling
    • Real-time reporting of calibrated concentrations for target compounds
    • Single-click transitions between shutdown, ready, and sleep states

Options

 

Vocus Reaction Cell and Sampling Inlet

  • Proprietary reagent ion source and ion-molecule reaction cell with axial DC field and RF-focusing.
  • Automated reagent ion switching.
  • Temperature controlled reaction cell, ambient temperature up to 120C.
  • Heated inlet system, up to 180 C.
  Sample Flow Rate 50-500 sccm typical 100 sccm
  Operating Pressure 0.5 – 5 mbar typical 1-2 mbar
  Axial Gradient Uniform linear field 0-5 V/mm
  Reagent Ions H3O+, NO+,O2+, NH4+

Vocus PTR-TOF Publications

2020

  1. Claflin, M. S. et al. An in situ gas chromatograph with automatic detector switching between Vocus PTR-TOF-MS and EI-TOF-MS: Isomer resolved measurements of indoor air. Atmos. Meas. Tech. Discuss. In review 2020. DOI:10.5194/amt-2020-271
  2. Mehra, A. et al. Evaluation of the chemical composition of gas- and particle-phase products of aromatic oxidation. Atmos. Chem. Phys. 2020DOI: 10.5194/acp-20-9783-2020
  3. Bruderer, T. et al. Detection of Volatile Organic Compounds with Secondary Electrospray Ionization and Proton Transfer Reaction High-Resolution Mass Spectrometry: A Feature Comparison. J. Am. Soc. Mass Spectrom 2020In Focus | DOI: DOI: 10.1021/jasms.0c00059
  4. Li, H. et al. Source identification of atmospheric organic vapors in two European pine forests: Results from Vocus PTR-TOF observations.  Atmospheric Chemistry and Physics In review 2020DOI: 10.5194/acp-2020-648
  5. Wang, Y. et al. Detection of gaseous dimethylamine using Vocus proton-transfer reaction time-of-flight mass spectrometry. Atmospheric Environment 2020DOI: 10.1016/j.atmosenv.2020.117875
  6. Wang, Y. et al. Oxygenated products formed from OH-initiated reactions of trimethylbenzene: Autoxidation and accretion. Atmospheric Chemistry and Physics 2020DOI: 10.5194/acp-20-9563-2020
  7. Li, H. et al. Terpenes and their oxidation products in the French Landes forest: insight from Vocus PTR-TOF measurements. Atmospheric Chemistry and Physics 2020. In Focus | DOI: 10.5194/acp-20-1941-2020 

2019

  1. Holzinger, R.; et al. Validity and limitations of simple reaction kinetics to calculate concentrations of organic compounds from ion counts in PTR-MS. Atmos. Meas. Tech. Discuss 2019. DOI: 10.5194/amt-12-6193-2019

2018

  1. Riva, M.; Rantala, P.; Krechmer, J. E.; Peräkylä, O.; Zhang, Y.; Heikkinen, L.; Garmash, O.; Yan, C.; Kulmala, M.; Worsnop, D.; and Ehn, M. Evaluating the performance of five different chemical ionization techniques for detecting gaseous oxygenated organic species. Atmos. Meas. Tech. Discuss 2018.  In Focus | DOI:10.5194/amt-12-2403-2019
  2. Krechmer, J.; Lopez-Hilfiker, F; et al. Evaluation of a New Vocus Reagent-Ion Source and Focusing Ion-Molecule Reactor for use in Proton-Transfer-Reaction Mass Spectrometry. Analytical Chemistry 2018. In FocusDOI: 10.1021/acs.analchem.8b02641

Application Notes

Conference Presentations

Customer Research

TOFWERK Publications

Webinars

White Papers

Product Information

Background Knowledge About Vocus PTR-TOF

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