https://varshinicb.com/writing Short writing on instrumentation, sensing, software and building companies. en Fri, 23 Oct 2026 10:06:02 GMT https://varshinicb.com/writing/electrochemistry-leaves-the-bench https://varshinicb.com/writing/electrochemistry-leaves-the-bench Thu, 22 Oct 2026 09:00:00 GMT A potentiostat is the most useful instrument most people have never heard of. The reason it stays in the lab is not physics — it is packaging. https://varshinicb.com/writing/screen-printed-electrodes-explained https://varshinicb.com/writing/screen-printed-electrodes-explained Tue, 20 Oct 2026 09:00:00 GMT Three contacts, one drop of sample, and a surface you throw away after each measurement. Why the electrode matters as much as the instrument. https://varshinicb.com/writing/ten-parts-per-billion https://varshinicb.com/writing/ten-parts-per-billion Sun, 18 Oct 2026 09:00:00 GMT The drinking-water limits for lead are small enough to sound theoretical. They are not — they are the reason sample handling, not just instrumentation, has to be right.