Selecting the Optimal Quadrupole Size

Whether you are using a quadrupole as a mass spectrometer analyzer,or to size select ions for your experiment, it is important to use the quadrupole that will give you the best results.

With the proliferation of quadrupole technology over the last 60 years, the 6 mm quadrupole has become the most common size. This is due largely to the relatively low cost of producing the RF supplies that drive them. You will find 6 mm quadrupoles used in analytical laboratory systems like GC/MS, process analyzers and Residual Gas Analysis (RGA). However, in a high performance research analyzer, the size of the quadrupole will determine the quality of your data.

The key performance attributes for quadrupoles include mass range, resolution and transmission. Better transmission means you get more signal for analysis and lower detection limits. In an ion selection application, higher transmission means less time collecting the ions you need. Resolution gives you the ability to see distinct, individual peaks for ions of similar mass, in some cases, down to less than 0.05 Daltons apart. For a given RF power supply, as the quadrupole gets large, the transmission and resolution improve, while the mass range is reduced.

So how does mass range fit in? This depends completely on your requirements. Once you decide on the mass range that you need, you will always want to maximize your quadrupole size to get the best mass separation and the highest ion throughput possible.

Once a scientist decides to look beyond the 6 mm quadrupole mass spectrometer system (QMS) they may find navigating the options for selecting the right system a challenge. Extrel offers quadrupoles in three different sizes, 6 mm, 9.5 mm and 19 mm. Extrel is known for the stability and reliability of its RF power supply products which, when coupled with the appropriate quadrupole, gives you an analyzer optimized to your experiment.

Extrel has over 50 years’ experience in supplying quadrupole systems for advanced research, with an excellent reputation for performance and quality. Our application experts are available to help you choose the right system for your needs.

Discover the Advantage of Extrel.

What’s new

  • 4

    Catalysis: An Overview of Extrel’s Capabilities

    News | 5 Apr 2018

    Extrel instruments have been recognized for their exceptional performance by the world’s leading researchers for more than 50 years. Reliability and flexibility are complemented by the most comprehensive application, technical and on-site support in the industry. Read below to learn more:

  • extrel logo 65x72

    The University of Pittsburgh adds educational mass spectrometer to physics curriculum

    News | 30 Oct 2017

    The University of Pittsburgh has purchased Extrel’s educational mass spectrometer, the IQ-2000, for use in the Department of Physics and Astronomy, part of the Kenneth P. Dietrich School of Arts and Sciences.

  • 1


    Products | 21 Sep 2017

    Real-Time Heating Value Gas Analyzer

  • 1

    VeraSpec HRQ

    Products | 20 Sep 2017

    High Resolution Quadrupole Mass Spectrometer

  • Extrel logo 65x72


    News | 19 Apr 2017

    Industrial Process Mass Spectrometer

Search all our content