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Updated: Jun 19, 2026

A Method for Determination and Simulation of Permeability and Diffusion in a 3D Tissue Model in a Membrane Insert System for Multi-well Plates
Published on: February 23, 2018
DIRECT AND INDIRECT DETERMINATIONS OF PERMEABILITY
1Laboratory of Plant Physiology, Harvard University, Cambridge.
Abstract:
1. Methods are described for obtaining cell sap from Nitella without contamination. 2. Tests of the cell sap show that in a balanced solution of NaNO(3) plus Ca(NO(3))(2) there is a slow penetration of NO(3) and that the cell remains in a normal condition, but in pure NaNO(3) there is rapid penetration accompanied by injury. 3. Inasmuch as determinations of electrical conductivity give the same result it may be concluded that this method gives reliable information regarding permeability. 4. While observations on recovery from plasmolysis give similar results, the method is less satisfactory.
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