Abstract: The invention provides a permeation device (2) comprising a receiving vessel (6) having an aperture adapted for receiving an insert well (4). Both the vessel (6) and well (4) are used as either donor or acceptor compartments for permeability assays. The vessel (6) or well (4) comprises a porous suppor (8)t, which may comprise biological or biomimetic materials, adapted for a molecular entity to permeate therethrough. In one embodiment, a stirring member (24) disposed in the vessel (6) can provide solution agitation to reduce aqueous boundary layer thickness adjacent to the support (8). Boundary layer thicknesses can be reduced by a device (2) of the invention to less than about 15 um such that a molecular entity permeating the support closely approximates in vivo absorption and transport conditions.

Abstract: An apparatus for evaluating physicochemical properties of sample materials contained in an array of vessels includes: a light detector; a light source for transmitting a light beam through the sample material in a vessel to the light detector; an analyzer for processing data from the light detector to determine concentration-related properties of the sample material as a function of time; and a mixing system. The mixing system includes: a plurality of magnetic stirrer elements, each for being placed in a sample material in a different one of the array of vessels; an array of magnetic drive elements, each associated with a different one of the array of vessels and being magnetically coupled with a magnetic stirrer element in an associated vessel; and a drive mechanism coupled to the array of magnetic drive elements for simultaneously moving each of the magnetic drive elements relative to an associated vessel.

Abstract: An apparatus for evaluating physicochemical properties of sample materials contained in an array of vessels includes: a light detector; a light source for transmitting a light beam through the sample material in a vessel to the light detector; an analyzer for processing data from the light detector to determine concentration-related properties of the sample material as a function of time; and a mixing system. The mixing system includes: a plurality of magnetic stirrer elements, each for being placed in a sample material in a different one of the array of vessels; an array of magnetic drive elements, each associated with a different one of the array of vessels and being magnetically coupled with a magnetic stirrer element in an associated vessel; and a drive mechanism coupled to the array of magnetic drive elements for simultaneously moving each of the magnetic drive elements relative to an associated vessel.

Abstract: This invention improves the PAMPA (parallel artificial membrane permeability assay) method used in pharmaceutical, biotechnological, and agrochemical R&D. This new high-throughput method and apparatus for measurement of permeability and membrane retention of compounds overcomes shortcomings of prior art and includes sensitivity and speed enhancing reagents. The phospholipid membranes used here consist of 10–74% wt/vol soybean lecithin extract dissolved in dodecane. Concentrations are measured by direct UV spectroscopy. To reduce membrane retention, surfactants, cyclodextrins, or water-soluble lipophilic polymers with low UV absorption are used in the acceptor comparment of the permeation cells and create an artificial sink state. A pH gradient established between donor and acceptor solutions creates a secondary sink state. This “double-sink” makes successful modeling of passive-diffusion transport of molecules possible.

Abstract: The invention described here improves the PAMPA (parallel artificial membrane permeability assay) high-throughput method used in lead compound selection and optimization in pharmaceutical and biotechnological research and development, and for identifying active compounds with the right plant distribution properties in agrochemical research and development. The invention described here is a robust method and apparatus for measurement of two physical properties, permeability and membrane retention of compounds, which overcomes several of the shortcomings in the prior art. This invention includes reagents specifically designed for enhancing the sensitivity of the assay, to allow a UV detection system to be used for concentration measurements, to accurately estimate and compensate for the effects of membrane retention and unstirred water layer, and to increase the speed of the assay.