There are disclosed an ISE slide element and potentiometric measurement of assaying, using a slide element that is positionally insensitive about an axis of symmetry. This is achieved by accessing one of the electrodes in the center of the slide element, and the other in an annular groove centered on...http://www.google.com.au/patents/US5330625?utm_source=gb-gplus-sharePatent US5330625 - Round potentiometric slide elements and method of using the same
