Abstract: This invention provides methods and apparatuses for the rapid assessment of cell permeability by a drug. More particularly, described herein a method of determining membrane permeability (influx and/or efflux) of a cell to a drug, the method including: (a) obtaining a biological sample; (b) dispersing at least one cell from the biological sample to a discrete location; (c) exposing the at least one cell to one member of a drug panel in a drug solution, wherein the drug panel is composed of drugs of a given concentration; (d) incubating the at least one cell from the biological sample in the drug for a given time; (e) obtaining at least one electro-analytical measurement of the discrete location adjacent the at least one cell.