Abstract: Disclosed is a method and apparatus for the non-invasive determination of one or more preselected analytes in a body fluid expressed through the skin. The fluid is collected in a dermal concentration patch and concentrated by driving off a portion of the substantial water fraction under the influence of body heat. The analyte is optimally complexed with an immobilized specific binding partner and an indicium of the presence of the analyte is visually expressed. The patch may comprise a plurality of test zones for screening for a plurality of analytes. Additional positive and negative control zones are also disclosed. The patch may comprise a feature to detect tampering with the patch to produce false negative results, especially when used in screens for drugs of abuse. In addition to being useful as a drug of abuse screen, the patch is useful for diagnostic purposes.

Abstract: A system for filtration of matter from a liquid suspension through a membrane uses a rotor within a concentric shell rotating with a surface velocity which, together with the rotor-shell gap and suspension viscosity, establishes vigorous vortex cells about the rotor. At least one of the rotor and shell surfaces include a filter membrane. Tangential velocity components at the membrane surface constantly sweep the membrane surface to limit cell deposition tendencies while constantly replenishing the medium to be filtered. The vortex cells are established along the length of the membrane despite the constant extraction of filtrate and the resultant change in physical characteristics of the suspension.

Abstract: Blood separation is accomplished by alternately extracting blood from and reinfusing blood into a donor by way of a single needle while simultaneously and continuously separating the extracted blood into constituents. A harness set applicable to a hemapheresis instrument includes a dual-compartment reservoir. A first compartment stores blood during extraction for supply to the separator during reinfusion. The second compartment stores packed cells during collection for return to the donor during reinfusion. The collection and reinfusion cycles are alternated rapidly to preclude clotting in the un-anticoagulated portion of the harness tubing between the venepuncture needle and the Y-connection with the anticoagulant line.

Abstract: Method and apparatus are provided for machine separation of blood into blood components, wherein a preselected fluid such as anticoagulant is added to at least two different locations through the fluid flow path of the set, in order to promote the different functional characteristics in different blood components. The method results in reduced incidence of citrate reaction in the blood donor and increased platelet yield in platelet rich plasma collected during the procedure.

Abstract: Method and apparatus for machine separation of blood and blood components that utilizes improved administeration of anticoagulant to the red cell suspension output. Anticoagulant is added to incoming whole blood in an amount sufficient to prevent clotting of the whole blood in the flow path upstream of the blood component separator, but in an amount insufficient to prevent clotting of the red cell suspension created by the separator. Anticoagulant is added to the red cell suspension downstream of the separator in order to prevent clotting. By adding an additional aliquot of anticoagulant to the red cell suspension, the amount of anticoagulant added to whole blood before separation can be reduced or eliminated, resulting in an increase in platelet yield during the blood component separation step.

Abstract: Disclosed is a method and apparatus for the non-invasive determination of one or more preselected analytes in a body fluid expressed through the skin. The fluid is collected in a dermal concentration patch and concentrated by driving off a portion of the substantial water fraction under the influence of body heat. The analyte is optimally complexed with an immobilized specific binding partner and an indicium of the presence of the analyte is visually expressed.

Abstract: A system and method for cleaning contaminants from shed blood to enable reinfusion of a cell concentrate in the patient employs successive rotary membrane filtering stages in which Taylor vortices are generated. Shed blood led into the first rotary membrane stage is filtered to produce a hematocrit in the range of 50-60 with some of the waste matter being removed. The intermediate cell concentrate is passed to the second filter stage where further waste matter is initially extracted. At any intermediate region, however, a major amount of wash solution is fed into the concentrate and effectively mixed therein. In the remaining length of the second filter stage, waste matter is entrained in the wash solution and both waste and wash solution are filtered out to provide a cell concentrate from which the great majority of contaminants have been removed.

Abstract: A system for continuously esparating lighter and intermediate density matter, such as plasma rich in platelets from whole blood moves blood through a diverging centrifugation gap between inner and outer walls of a rotor rotating about a central axis within an outer housing. The centrifugation action creates layered flow along an intermediate section. However by crating trailing wakes in the gap between the rotor and housing, localized remixing patterns tending to move in the opposite direction are induced in the layered matter. Platelet rich plasma may then be extracted through adjacent platelet concentrate ports on the inner wall of the rotor. An interior passageway system passes the platelet rich plasma to a platelet concentrate reservoir. Recirculation of blood in the rotor-housing gap between the output and input, and pumping action provided by the diverging centrifugation gap, aid in enhancing throughput and concentration levels.

Abstract: Disclosed is a method and apparatus for the non-invasive determination of one or more preselected analytes in a body fluid expressed through the skin. The fluid is collected in a dermal concentration patch and concentrated by driving off a portion of the substantial water fraction under the influence of body heat. The analyte is optimally complexed with an immobilized specific binding partner and an indicium of the presence of the analyte is visually expressed.

Abstract: A system for continuously separating lighter and intermediate density matter, such as plasma rich in platelets from whole blood moves blood through a diverging centrifugation gap between inner and outer walls of a rotor rotating about a central axis within an outer housing. The centrifugation action creates layered flow along an intermediate section. However by crating trailing wakes in the gap between the rotor and housing, localized remixing patterns tending to move in the opposite direction are induced in the layered matter. Platelet rich plasm may then be extracted through adjacent platelet concentrate ports on the inner wall of the rotor. An interior passageway system passes the platelet rich plasma to a platelet concentrate reservoir. Recirculation of blood in the rotor-housing gap between the output and input, and pumping action provided by the diverging centrifugation gap, aid in enhancing throughput and concentration levels.

Abstract: A system and method for cleaning contaminants from shed blood to enable reinfusion of a cell concentrate in the patient employs successive rotary membrane filtering stages in which Taylor vortices are generated. Shed blood led into the first rotary membrane stage is filtered to a hematocrit in the range of 50-60 with some of the waste matter being removed. The intermediate cell concentrate is passed to the second filter stage where further waste matter is initially extracted. At any intermediate region, however, a major amount of wash solution is fed into the concentrate and effectively mixed by the Taylor vortices. In the remaining length of the second filter stage waste matter is entrained in wash solution and both waste and wash solution are filtered out to provide a cell concentrate from which the great majority of contaminants have been removed.

Abstract: A centrifugal separator system is provided for extracting lighter matter from a liquid suspension. The separator includes a housing having an axis, an inlet port, a lighter matter outlet port and a heavier matter outlet port spaced from the inlet port. A rotatable interior double shell rotor is disposed within the housing. The rotor includes outer and inner shells and defines a centrifugation gap therebetween. The rotor is spaced from the housing by a flow gap. The outer shell includes means providing communication between the centrifugation gap, the inlet port and the heavier outlet port. Means are provided in the double shell rotor for conducting lighter matter from the centrifugation gap to the lighter matter outlet port.

Abstract: A limb stimulator is engaged with a lower portion of a patient's limb for facilitating sustained venous blood flow therefrom toward a phlebotomy needle when the stimulator is activated. The stimulator may be an inflatable squeeze bulb adapted to engage a human hand and to be squeezed thereby when inflated. The stimulator may also, or alternatively, include a pressurizable member substantially surrounding a lower portion of the limb and adapted to apply external pressure thereto when periodically pressurized so as to periodically (e.g., in approximate synchronism with natural pulsitile blood movements in the limb) express venous blood upwardly through the limb to the needle. Inflation of the hand-held squeeze bulb serves as a tactile stimulus to the patient to assist in venous blood movements towards the needle by muscle and tendon flexure in the lower part of the limb and may also be periodically activated (e.g., in approximate synchronism with natural pulsatile blood movements in the limb).

Abstract: An adaptive filter concentrate flow control system and method includes a filter system, a pumping system driving feed fluid, concentrate and filtrate flowing through the filter system and a flow control system controlling the pumping system to maintain optimum filtrate flow rates along a control curve in a transmembrane pressure--feed fluid rate--filtrate flow rate three dimensional space. Actual sensed operating point data is used to locate the control curve so as to assure an optimized filtrate flow rate at which reversible blocking of the membrane has begun to occur without irreversible plugging. The system is advantageously employed to control and maximize the flow of plasma in a plasmapheresis system.

Abstract: A disposable diagnostic plasma filter dispenser includes a low cost disposable container and a rotor drive for rotationally energizing a rotor within the container. The disposable container is particularly suitable for drawing and dispensing blood samples for clinical analysis and includes a tube shaped outer wall having a frangible dispenser outlet cover, a close fitting inner tube supporting a filter membrane and a unitary rotor disposed for axel free rotation and axial translation within the inner tube in response to energization from the rotor driver. The rotor produces vortex enhanced filtration while maintaining a flow of filter fluid through the filtration gap and creating a transmembrane pressure.

Abstract: A method of wetting a plasmapheresis filter with anticoagulant in a plasmapheresis system having a venepuncture needle, a plasma separation device connected in series by a fluid conduit, including operating the system such that an initial limited volume charge of anticoagulant is introduced into the conduit (for wetting the filter of the separation device) in advance of whole blood flowing from the donor towards to the separation device (and pushing the anticoagulant charge ahead of the whole blood into the separation device).

Abstract: A tubing or harness set is provided having first and second portions sequentially applicable to a microprocessor-controlled hemapheresis instrument for generating platelet concentrate. The first portion includes a reservoir having dual compartments and a separator. The instrument and the first portion of the harness set alternately collect whole blood from the donor and reinfuse packed cells into the donor while simultaneously continuously separating whole blood into packed cells and platelet-rich plasma. Upon collection of a predetermined quantity of platelet-rich plasma, the donor is disconnected form the phlebotomy needle of the harness, the first harness portion is removed from the instrument and the second harness portion is applied to the instrument. The second harness portion includes a separator for receiving platelet-rich plasma from the collection container of the first harness portion and separating such plasma into platelet concentrate and platelet-depleted plasma.

Abstract: A disposable biomedical rotating filtration system for processing fluids in a closed environment includes a rotor mounted for rotation on a pivot pin, a seal between the rotor and pivot pin, an external permanent magnet drive mechanism, and a star shaped drive element mounted on the rotor for rotating the rotor in response to a magnetic field induced by the permanent magnet of the drive mechanism. The drive element on the rotor is stamped from an inexpensive non-permanent ferromagnetic sheet metal and has a configuration and position in relation to the center of said magnetic field such that said drive element receives sufficient torque for driving said rotor and sufficient seal force is applied on the rotor to provide fluid tight seal between the rotating rotor and the seal. The pivot pin is molded from a hard plastic material such as a polyamide base resin having a low coefficient of friction and good lubriciousness.

Abstract: A reliable flow rate plasmapheresis system includes a rotating enhanced vortex type of membrane filter coupled to receive a flow of anticoagulated whole blood and separate concentrate and filtrate in responses thereto. An anticoagulant pump is coupled to mix controlled amounts of anticoagulant with the input blood flow. Degradation of plasma flow rate during multiple extraction-reinfusion cycles is inhibited by selecting the starging anticoagulant pH value and controlling the anticoagulant flow rate relative to the whole blood to establish a final whole blood/plasma pH value in the range of 6.8 to 7.2, with an anticoagulant to blood ratio in the range of 1:6 to 1:25.

Abstract: A hemapheresis system and method in accordance with the invention comprises a stationary closed housing concentric about a central axis and a feed system that moves blood upwardly from the housing lower end toward an outlet port adjacent a substantially closed upper end. Within the stationary housing is a double walled rotor concentric with the housing and rotatable by magnetic means within the housing on sealed end bearings. The space between the rotor walls defines a centrifugation gap into which whole blood is passed and within which centrifugal separation takes place as the rotor is spun at a relatively low rate. Whole blood also seeks to flow upwardly in the space between the rotor and housing, but this path is arranged to have a substantially higher flow impedance, so that the preferential path is within the centrifugation gap.