SensNews November 2018

7 Sensor100 November 2018 Sensor People in the News Simon’s Electrodes Over the past few months, Prof Andrea Sella’s (UCL) column in ChemistryWorld has talked about electrochemistry topics and people (Cremer and Heyrovsky) and the July issue is devoted toWilhelm Simon (1929 - 1992) at ETH in Switzer- land. I knewWilli Simon quite well in the 1970’s when I was at Technicon Instruments (now Siemens) and we adopted his potassium electrode to include in SMAC (Sequential Multiple Analyzer with Computer) which performed 20 tests on blood serum at the rate of 120 tests per hour. SMAC used Technicon’s well established “bubble” technology which used tubes and pumps to move samples around. It is always inter- esting to see advances in microfluidics which we invented on a much larger scale at Technicon 40 years ago. SMAC pioneered the use of ISE’s in clinical chemistry; we had 25 seconds to obtain a reading which someone, I suspect arbitrarily, had decreed 8 seconds muct be “flat”. This was considered well beyond the capa- bilties of ISE’s at the time. We (a small group including Sal Pace, Jim Scott and Bill Calogero) acheived that goal, and the instrument gained FDA approval in the early 1970’s. Willi’s valinomycin potassium electrode is one of the great ISE’s sucesses in terms of sensitivity and selectivity over sodium, in particular; Jim Ross and Martin Frant at Orion had a similar success with their fluoride electrode. AlthoughWilli tried to create other ISE’s none were as successful at the K + electrode; in my own lab we compared several Ca 2+ electrodes in blood electrolytes, but the Simon ver- sion was less effective than an ISE from Radiometer. Willi was an affable character, and my wife and I once took him to dinner in Manhattan, about a 45 minute drive fromTarrytown. He was amazed that anyone would drive 45 minutes to a restaurant; in Zurich 10 minutes would be the most. We didn’t tell him that when we dropped him off at his hotel in Tarrytown, we then a futher 45 minutes drive to our home. [Michael Brand]