Analytical devices based on diffusion boundary layer calibration and quantitative sorption

摘要

A method and device for determining the concentration of analytes in a sample. The device has a surface with an extraction coating thereon. The method is carried out while the sample is highly agitated to maintain a substantially constant boundary layer. The sample is brought into contact with the coating for a limited time so that all the analytes that pass through the boundary layer are adsorbed by the coating. The amount of analytes in the coating is determined and the concentration of those same analytes in the sample is then calculated from the diffusion coefficient of the analytes. The device is first calibrated using analytes of known concentration.