A modified horizontal capillary puller for fabrication of patch-clamp pipettes

A simple low-cost modification to a conventional horizontal two-stage micropipette puller is described. It allows the production of pipettes suitable for patch-clamp studies. It requires that the hard-pull stage of the fabrication process be disabled and two heating cycles, each with a different heating filament temperature, be employed. The modification is described specifically for an Industrial Science Associates, Inc. M-1 micropipette puller. However, in principle it should be applicable to any horizontal two-stage puller using a solenoid to generate the pull force.