Improved radioactivity detector for fused-silica capillary columns

摘要: Abstract 14 C-labeled and unlabeled organic compounds eluting from fused-silica capillary columns were detected by the parallel combination of a radioactivity detector (RAD) flame ionization (FID). The RAD consists small-volume counter tube ancillary electronics. It is constructed readily available parts. For maximum signal-to-noise ratio, operated at 70% counting efficiency. resulting background less than 5 cpm. instrumentation delivers high chromatographic efficiency eliminates combustion artifacts. Radioactive peaks are 12 sec wide, while detection limit ca. 440 cpm (0.2 nCi) for with k ′ ⩽ 5. No degradation in column performance apparent FID trace.