A NEW DATA-ACQUISITION SYSTEM FOR THE MEASUREMENT OF THE NET WATER FLUX ACROSS EPITHELIA

We describe a computer-based data-acquisition system designed for the measurement of net water flux across epithelia. It is based on the det ection of a liquid meniscus position in a capillary tube using an elec tro-optical device. Then the data are digitized, transferred to the co mputer main memory and saved in a file. The advantages of the system a re: (a) to measure net water transfer with an accuracy of 50 nl; (b) t o switch from absorptive to secretory conditions in real time; (c) dat a are directly digitized to be analytically, graphically and statistic ally treated; (d) the specially developed software allows change of ti me intervals for data acquirement and the scale in graphic events; (e) the software also allows recall to the monitor screen of graphics fro m previous tests or to print them on paper; (f) a simple mechanical st ructure, saving maintenance and time; and (g) high reliability. (C) 19 97 Elsevier Science Ireland Ltd.