The Lumicks C-Trap® is a correlative single-molecule system combining optical tweezers with multicolour fluorescence imaging. This enables simultaneous manipulation of trapped molecules of interest and imaging of the dynamics of individual binding events

The optical tweezer element of this setup utilises focused laser light to trap, manipulate and apply calibrated forces to microscopic refractive objects. Such objects could include a molecule of interest or, more typically, beads functionalised for tethering other objects such as single DNA molecules. Imaging of fluorescently-labelled interacting species and/or trapped objects utilises confocal scanning. The C-Trap® setup also incorporates a five-channel microfluidic device designed for laminar flow conditions to allow for the rapid movement and exposure of samples to different reagents. This single-molecule approach offers insight not granted by traditional bulk experiments including access to subpopulations, transient intermediates and heterogeneous behaviour.

Applications include, but are not limited to, real-time visualisation of DNA-manipulating enzymes, tracking the conformational landscape of proteins, the study of phase separation and following folding and unfolding of DNA/RNA structures and proteins.

The Wolfson Bioimaging Facility’s C-Trap® was installed in August 2022. Confocal imaging can be performed using three excitation lasers (488 nm, 561 nm and 638 nm), each with associated bandpass filters (525/45, 600/50 and 680/42), making the system also suitable for single-molecule fluorescence resonance energy transfer (smFRET) studies. Our system has a quadruple optical tweezers trap configuration allowing the trapping of multiple objects simultaneously and their independent manipulation. 

Lumicks C-Trap technical specifications (PDF, 144kB)

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