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Stochastic force dynamics generated by a Chlamydomonas microswimmer study with IMPETUX’s exclusive patented technology

Stochastic force dynamics generated by a Chlamydomonas microswimmer study with IMPETUX’s exclusive patented technology

Stochastic force dynamics generated by a Chlamydomonas microswimmer in Optical Tweezers studied using the photon momentum method:

 

Here we share an interesting publication from Dr. Ahmed Lab from the Department of Physics of the California State University Fullerton et al.

 “Stochastic force dynamics of the model microswimmer Chlamydomonas reinhardtii: Active forces and energetics“

In this paper the authors study the stochastic force dynamics of a model microswimmer algae (Chlamydomonas reinhardtii), using a combined experimental, theoretical, and numerical approach.

For the experimental work they directly measured the stochastic forces generated by these algae using an optical trap via the photon momentum method.

“Optical trapping to manipulate and study microswimmers is not new”

they state

“ however, in-situ calibration is typically challenging. Here , direct force measurements are possible due to recent advances in optical trap calibration known as the photon momentum method…..”.

For this, the authors used an optical tweezers system from IMPETUX . IMPETUX products are the only optical tweezers systems in the market incorporating this patented calibration-free force-sensing technology.

The following video (courtesy of Dr Ahmed),  shows a optically trapped Chlamydomonas microswimmers and real-time X-Y force measurement.

 

The authors conclude that the photon momentum method, a part of providing other several advantages, is a key technique to study the force dynamics of microswimmers with complex force patterns not previously accessible.

You can have a look at the details of the results obtained and conclusions here

Enjoy the reading!

Congratulations to the authors!

 

📌If you are interested in how our optical tweezers system: SENSOCELL can be used for cell micro-rheology measurements, cell nucleus indentation experiments, neuron mechanosensation studies, among others applications,  do not hesitate to have a look at the application section or directly contact us.

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Fig. 1

Time dependence of trap position (top), force signal (middle) and Ca2+ fluorescence signal (bottom) recorded during a membrane tether pulling experiment. The force and Ca2+ ion channel activity signals exhibit negative correlation.

Fig. 2

Force and displacement data for two beads stimulated at frequencies of 4 Hz and 0.25 Hz. The progressive reduction of the beads displacement is in concomitancy with an increase of the applied force and loading rate.

Fig. 1

Schematic representation of the optical tweezers experiment. A fibronectin-coated bead is trapped, brought into contact with the cell membrane and stimulated with oscillations at different frequencies.

Fig.2

Time dependence of trap 1 and trap 2 position (top) and force (bottom) data along the different steps of the described dual tether pulling experiment.

Fig.1

Confocal video of the described dual tether pulling assay performed on a neuron axon. Courtesy of M. Krieg lab (ICFO).

Fig. 1

Time dependence of trap position (top), force signal (middle) and Ca2+ fluorescence signal (bottom) recorded during a membrane tether pulling experiment. The force and Ca2+ ion channel activity signals exhibit negative correlation.

Video 1

Confocal video showing a DVA neuron Ca2+ ion channel activity in a dynamic optical trapping assay. The pulling rate applied to the membrane tether is progressively increased. Scale bar = 5µm. Acquired at 10Hz.