Patent ID: 6668229
Filing Date: 2003-12-23
Classification: G01N

Abstract:
A method of testing a sample of cells suspended in a liquid medium to determine a measure of cell permeability of cells in the sample comprising:a) feeding the sample cell suspension into another liquid medium having a continuously changing osmolality gradient to produce an altered sample cell suspension by attempting to induce a flow of fluid across cell membranes and thereby change the shape of cells in the sample suspension; b) passing the altered cell suspension through a sensor; c) measuring a property of the altered sample cell suspension which is related to volume of the cells; d) recording a sensor measurement for the cells; e) subjecting the recorded sensor measurements to analysis to identify a value of the recorded measurement at which cells in the altered sample cell suspension achieve a spherical shape; f) determining the volume of the cells in the altered sample cell suspension based on analysis of the recorded measurements of step (e) and calculating the surface area of the cells from the volume determination; and g) calculating cell permeability as a measure of the volume of fluid which crosses cell membranes as the cells undergo a change in shape in response to continuously changing osmolality.