Tweezers for plunge-freezing cryo-TEM sample preparation systems have remained the same across all platforms and generations.  Fighting to get the tweezer dovetail on and off of the plunger - and  fighting with a plastic "O-ring" to grasp and release the delicate TEM grid.  NanoSoft's Cryo-Tweezers work with all generations of the FEI Vitrobot and offer multiple features that make the sample preparation process more dependable and effortless for the user.  Experienced sample preparation experts will find it a smoother process.  Early experiences for beginners will become less stressful, leading to fewer lost grids and more successful imaging as they prepare their first samples. And we repair our Cryo-Tweezers for much less than the price of a new pair (click for details)!
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Spring-loaded Plunge Clamp: The Vitrobot tweezers interface with the FEI Vitrobot plunger with a dovetail geometry.  The tight mate of the dovetail makes it difficult to attach and detach the tweezers, and is sometimes difficult to control, leading to crashing the sample grid into the ethane cup walls.  Our Plunge-Clamp is spring loaded and when pinched open is easy to attach to, and remove from, the plunge arm.  When closed in its natural state, the clamp attaches securely to the dovetail at the end of the plunge arm.  The clamp self-centers to align the tweezers axis with the axis of the plunger rod to ensure that it plunges safely through to the liquid ethane.
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Modified Reverse-Action Tweezers: The FEI Vitrobot tweezers are positive action, so an "O-ring" is utilized to keep the tweezers closed on the sample grid.  This requires you to carefully slide the O-ring up and down the tweezers, while holding the tips closed, whenever you want to grab or release the grid.  Our reverse action tweezers hold the grid securely in their natural state and require just a small pinch to release the grid into the grid box. Commercially available reverse-action tweezers are too wide for the Vitrobot blotting arms - our modified version fits between the blotting pads without interfering with the blot.