Simultaneous patch-clamp and photometric fluorescence ratio measurements of optical probes for ions using a computer-based data acquisition system, PhoCal

B. Somasundaram, J. Hoyland, John Dempster, J. Riley, W.T. Mason

Research output: Contribution to journalConference Contributionpeer-review


This demonstration will present a new computer program and analytical system - PhoCal - which permits the simultaneous measurement of (a) low light levels of fluorescence from optical probes for ions and (b) up to two channels of physiological data which can include patch-clamp current and voltage, or voltage from other probes such as extracellular pH electrodes or other transducers and (c) an event marker channel. The system is PC-based and uses high speed analogto-digital circuitry operating in parallel with a two-channel photon counter which collects data from one or two photomultiplier tubes. All data is logged
directly to hard disk and the system can operate at speeds in excess of an aggregate of 1000 samples per second.
Original languageEnglish
Pages (from-to)P63-P63
Number of pages1
JournalJournal of Physiology
Issue numberSuppl.
Publication statusPublished - 1992
EventThe Physiological Society Cambridge Meeting 1991 - Cambridge, United Kingdom
Duration: 18 Jul 199120 Jul 1991


  • patch clamp
  • photometric fluorescence
  • PhoCal

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