A filtration device having at least one filter packet and a retainer is described. The filter packet includes a membrane having at least a first opening therethrough. The filter packet further includes a retentate screen in fluid communication with the first side of the membrane and a filtrate screen in fluid communication with the second side. The retentate screen includes a permeable material and a seal around an outer perimeter of the permeable material. The permeable material has at least a feed port-defining zone in fluid communication with the first opening. The filtrate screen includes a permeable material and at least a feed port-defining zone in fluid communication with the first opening. The feed port-defining zone of the filtrate screen includes a seal around a perimeter thereof. The filtrate screen has a perimeter open to a filtrate collection area.