A screening receptacle intended to concentrate a fluid clinical specimen [e.g., serum, urine, cerebrospinal fluid (CSF)] by filtration prior to in vitro diagnostic investigation. It is in the form of a container (e.g., tube, multi-well reservoir) with a semi-permeable filtering membrane, whereby specimen suspension particles [e.g., tissue culture extracts, cells, antigens, antibodies, proteins, hormones, DNA, RNA, column eluates, salts] are retained in a recoverable sub-volume of the specimen after filtration (e.g., by centrifugation, or absorption). This is a single-use device.