Stopped-flow/quench flow


Microvolume quench flow

A unique design enables the QFM-4000 to trap and identify reaction intermediates. The device is also commonly used for analysing enzymatic reactionq, DNA cleavage or single turnover reactions.


Quench-flow is a kinetic technique where a reaction is initiated by mixing two samples. The reaction ages in a delay line before being stopped after a user-defined ageing time, by mixing with a solution called the quencher. The aged solution is then collected at the exit of the quench-flow and is analyzed by external analytical methods.

Quench-flow is generally used to trap and identify reaction intermediates and to understand complex reaction mechanisms. It is also widely used for analyzing enzymatic reactions, DNA cleavage or single turnover reactions.




Microvolume quench-flow

Microvolume operation is now an absolute requirement for most quench-flow users as samples become increasingly valuable. The QFM-4000 is designed to minimize all internal volumes. Not a single drop of precious material is lost in the priming lines. The sub-microvolume precision of the motor drives ensures a minimum sample consumption. Only 10µl of sample is required for a successful experiment, and a complete kinetics run dataset can be obtained starting from a 200µl stock.

10 years warranty

Bio-Logic offers a 10 years warranty on its stepping motors. Our 10 years warranty reflects our confidence in the high quality of our design, engineering, and product performance.

Bio-Logic instruments are designed to be future-proof. They are instruments that will withstand the tests of time, the rigors of the laboratory and the ever-increasing demands of your research.

The QFM-4000 is based on a single delay line design. Aging times from 4 ms to several seconds can be obtained without any hardware change or calibration process. The combination of the small delay line with an innovative pulse mode to deliver solutions makes this microvolume (operation possible).

Biokine software

Bio-Kine is a powerful and comprehensive software designed for the expert user, but also easy to use for occasional users. Once injection volumes for each syringe have been entered, the user only needs to indicate the ageing time desired. The duration and speed of the phase are then automatically calculated and adjusted to meet the user’s parameters. The QFM-4000 is the most user-friendly and user-powerful quench-flow interface on the market. With only one parameter to change between experiments, a 20 point kinetics set can be done in less than 10 minutes.


  • Single mixing quench-flow application (= one mixing before quenching step)
  • 4 ms dead time
  • 10 µl of sample per experiment
  • Full recovery of sample
  • One delay line for the full aging time range
  • Easy operation
  • No calibration

Do I need to change delay line during my quench-flow experiment

No. you can run full series of ageing times using a single delay line. This is possible thanks to our innovative pulse mode.

How much sample I need for one experiment?

10 µl is the minimum recommended volume per shot. It means you can follow a complete kinetics with only a 200 µl stock

How temperature of quench-flow is controlled?

You just need to connect QFM-4000 to a water bath circulator. Syringes, mixers and flow lines are all under temperature control.

Request a quote.

Our team is ready to help

Contact us

Work smarter. Not harder.

Tech-tips, theory, latest functionality, new products & more.

Subscribe to the newsletter

No thanks!