The present invention provides a method and device for processing, sampling, and diluting a fluid and for detecting an analyte within the processed, sampled, and diluted fluid. In the method and device for processing, sampling, and diluting a fluid, an amount of fluid to be processed, sampled, and diluted is accepted by a porous membrane; a portion of the membrane saturated with the fluid is isolated thereby defining a predetermined sample volume of fluid; and the predetermined fluid volume sample is then released from the isolated membrane with a specified quantity of a fluid diluent to provide a diluted fluid sample. Analytes within the diluted fluid sample are detected by test strips in fluid contact with the diluted fluid sample.