The present invention is generally directed to a fluidized bed detector for continuous detection of biological and chemical materials comprising a fluidized bed of detecting elements suspended in a continuous flow system wherein the detecting elements remain in the system when a first force trying to move the detecting elements to the bottom of the system is balanced with a second opposing force of a flowing gas or liquid trying to move detecting elements to the top of the system and wherein the presence of a target molecule in the flowing gas or liquid disrupts the balance of the first and second forces causing the detecting element to exit the system. The release of the detecting element indicates the presence of the target molecule and may be captured, concentrated, or both for further evaluation by other assays or other means. Also disclosed is the related method of detecting biological and chemical materials using a fluidized bed detector.