Tip 2: T-Clips can be used to Attach a Muscle Fiber to an ASI Force Transducer and Length Controller

T-clips are small clips formed in a “T” shape and typically cut from aluminum foil.  The bottom of the T has a small hole in it.

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Figure 1 Drawing Showing T-Clip Dimensions

The top of the T is wrapped around the fiber and squashed down onto the fiber.  This leaves the vertical part of the T sticking out the end of the fiber.  A small hook is created and attached to the lever arm of the high speed length controller and a separate hook is attached to the force transducer.  In operation the hole in the T-clip is slipped over the hook to attach the fiber.

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Figure 2 T-Clip Attachment to Fiber

T-clips work well for low force applications such as single permeabilized fibers.  If you intend to test higher force fibers, for example frog fibers or bundles or strips, you may find that the tissue slips inside the T-clip and a more positive method of attachment such as tying should be looked at.

Refer to Y.E. Goldman, R.M. Simmons, Control of Sarcomere Length in Skinned Muscle Fibres of Rana Temporaria During Mechanical Transients, J. Physiology (1984), 350, pp. 497-518 for a good description of T-Clip fabrication and use.  Research groups routinely using T-Clips include Pieter de Tombe’s lab at Loyola in Chicago and Frank Brozovich at the Mayo.