A device for enhancing the visibility of the tip of a glass micropipette: application in neuroanatomy.

In neuroanatomical tract tracing glass micropipettes are used to make small injections of tracer in the brain. A problem is that, due to the poor visibility of the tip, the tip of a micropipette often breaks during filling with tracer solution. Therefore, a device was developed to enhance the visibility of the tip of glass micropipettes. The device is based on the principle that light of a light emitting diode (LED) is transmitted through the glass of the wall to the tip of a micropipette. Here, light converges and gives a brightly illuminated spot. In this set up micropipettes can be positioned accurately into a vial with tracer solution even without microscopic guidance.