JPCalcW - a 32-bit compatible, stand-alone Liquid Junction Potential Program

JPCalc  (Barry, 1994; J. Neurosci. Method., 51: 107-116) is a research/teaching program designed (1) to show graphically how junction potentials arise in a variety of different patch-clamp configurations and other electrophysiological situations; (2) to then enable the ready calculation of junction potential corrections, given the solution data, and (3) to show clearly how those junction potential corrections need to be applied to the appropriate physiological measurements [see review on junction potentials, J. Membrane Biol., 121, 101-117 (1991)].

The original JPCalc program has since been reprogrammed as a full Windows program  JPCalc for Windows, or JPCalcW, by Axon Instruments, Inc (Now part of Molecular Devices Corp.).  It is either available with their pClamp package, or as a stand-alone program from Professor Peter H Barry.  The cost of the JPCalcW software package on a CD, printed graphical Users' Manual and a laboratory license for multiple computers in the one lab/research group and cost of international express courier is A$175 (ex GST). Alternatively, an electronic version of the above package may be purchased for A$95 (ex GST).  In either case, from 2011, purchase is now organised via Professor Barry and payment is normally by credit card (VISA or MasterCard) to SDR Clinical Technology, Sydney (  So far JPCalc or JPCalcW has been purchased by far more than 100 laboratories in at least 17 different countries.   This program should also run with Apple Macintosh computers provided they have a fully compatible Windows/DOS emulation package.   Further details can be obtained by e-mailing

While JPCalc for Windows (JPCalcW) will run under 32-bit Vista, Windows 7 and earlier Windows, it will NOT DIRECTLY run under 64-bit Windows, as is true of a number of other programsHowever, JPCalcW will run in Windows XP-mode, under 64-bit Windows, which can be obtained free for Windows 7.


JPCalcWin - a 64-bit compatible, stand-alone  Liquid Junction Potential Program

 JPCalcWin is a new 64-bit compatible stand-alone liquid junction potential program, which is now available. There is also a free demonstration version of JPCaclWin, which may be downloaded from this website.  To download the program go to JPCalcWin Demo version.

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Peter H. Barry, June 2, 2014