Abstract: A lytic reagent composition and a kit of a lytic reagent system are disclosed for the rapid isolation, identification and/or analysis of at least five subpopulations of leukocytes from a whole blood sample. The composition and system have application to any environment in which the study and/or analysis of the leukocyte fraction of whole blood requires their isolation in their native or near native state. The lytic reagent composition of this invention comprises saponin and a carboxylic acid of the formula RCOOH wherein R is H or a C.sub.1-3 aliphatic hydrocarbon radial optionally substituted by one or more carbonyl and/or hydroxy groups. The kit of a lytic reagent system comprises the lytic reagent composition and a quench reagent.

Abstract: Specified classes and subclasses of leukocyte blood cells are identified by immunohematology procedures, based on utilization of antigenic determinants on the cell surface, their reactivity with antibodies which fluoresce under known circumstances, and identified by utilization of principles of flow cytometry or morphology.This invention particularly concerns improvements in the lysing and fixing method used prior to detection and identifying of the cells. In this method, a whole blood sample first is incubated with a reagent including antibodies to the cell subclass to be identified, the antibodies having directly or indirectly made fluorescently responsive to a particular light (e.g. argon ion laser). The red blood cells then are lysed with a reagent containing saponin. Next follows a leukocyte fixing treatment, preferably using a cross-linking dialdehyde composition, such as glyoxal or glutaraldehyde.

Abstract: A method and reagent system are disclosed for the rapid isolation, identification and/or analysis of leukocytes from a whole blood sample. The method and reagent system of this invention has application to any environment in which the study and/or analysis of the leukocyte fraction of whole blood requires their isolation in their native or near native state. One of the environments in which this invention can be used to advantage is in the performance of white cell differentiation on automated instrumentation designed for that purpose. In one of the preferred embodiments of this invention, the lytic reagent can contain a mixture of both formic and acetic acid, with the formic acid comprising the major component thereof and the acetic acid being present in only minor quantities, (if at all). This reagent system is used to selectively effect stromatolysis of red blood cells and create subtle modifications to the leukocyte population to enable their automated differentiation into five (5) sub-populations.

Abstract: Disclosed is a flow through particle analyzing cell differentiating apparatus for optical and electronic measurements on a stream of particles in which a hydrodynamically focoussed stream is passed into and through a point focussed beam of radiated energy whereby the beam is scattered by the stream to impinge upon light responsive signal operating members disposed adjacent the cell at angular positions relative to the beam axis of from about 10.degree. to 70.degree..

Abstract: A fluid container assembly including one large, relatively narrow container having an orthogonally shaped recess or depression in a wall portion thereof, and two small fluid containers nested within the recess. The recess has means therein engagable with mating means on each of the small containers for retaining the small containers within the recess against accidental dislodgement and so that the external walls of the containers are flush. Each fluid container is provided with a tamper indicating insert such that tampering renders difficult withdrawing fluid.

Abstract: A particle counter, of the type utilizing a Coulter(R) type aperature and a suction flow path downstream from the aperture, has a pair of electrodes on both sides of the aperture. A current is provided from the downstream electrode to the upstream electrode and pulses in the resulting voltage across the aperture are monitored to detect the passage of blood cells through the aperture. A grounded electrode is placed in the downstream flow path at a position near the package panel to isolate the cell counter from external electrical noise signals. An isolated high input inpedance amplifier is coupled to provide the monitored voltage to an inserted electrode positioned between the downstream aperture electrode and the grounded panel electrode. Because the inserted electrode and downstream electrode are then at the same voltage, no current flows through that portion of the flow path.

Abstract: An isotonic multipurpose blood diluent, and a method for use of this diluent with a weak lysing reagent system which is especially suitable for routine enumeration of traditional hemogram values, and also the determination of lymphoid-myeloid populations of leukocytes, particularly in automatic particle counting systems.This blood diluent is capable of affording accurate, reproducible test results. It is an osmotically balanced aqueous solution of preselected pH containing Procaine hydrochloride for maintaining erythrocyte morphology during operation, N-(2-acetamido)iminodiacetic acid (ADA) as a blood cell stabilizing agent, and bacteriostatic agents including sodium 1-hydroxypyridine-2-thione, and dimethylolurea which, together with the ADA, allow preferential determination of myeloid-lymphoid leukocytes, and other hematological values.The lysing agent is a mixture of an aqueous solution of at least one quaternary ammonium salt having surface active properties, and an alkali metal cyanide.

Abstract: A liquid sampling, metering and transfer valve assembly for providing plural dilutions of a single liquid sample comprising a pair of outer stationary elements sandwiching a rotatable element, the rotatable element carrying precise volume segmenting passageways, the outer elements carrying counterpart passageways for communicating to the exterior of the valve assembly, one outer element carrying loops each for storing a precise volume of diluent and the other valve elements carrying through passageways for communicating to and from said respective loops. A continuous body of sample is introduced into the valve assembly along a path through a pair of the segmenting passageays and a pair of aliquot portions isolated from said parth. The rotatable element is operated to direct one aliquot along with the content of one loop to an exterior location for mixing. The other sample aliquot is retained.

Abstract: A solenoid operated pinch valve including a housing and a hollow molded body coupled to said housing by a snap-on connection, a solenoid coil assembly seated within the housing, a plunger accommodated within said solenoid coil assembly for axial movement relative thereto controlled by energization of said solenoid coil assembly and between a pair of positions, said plunger having an end portion extending from the housing into said body and an opposite end portion received within said solenoid coil assembly, the body having a circumferential flange capable of being seated on one end of the housing and a pair of inflexible arms extending from the body in a coaxial direction relative thereto, said arms defining a passage for receiving a conduit across the path of movement of said plunger, a first orthogonal slot and a pair of resilient arms extending to the opposite end of the housing and engagable therewith in a snap-on coupling. One end of the plunger carries a second orthogonal slot.

Abstract: A rotary liquid metering and transfer valve assembly for a diluting system which includes a pair of stationary valve disc elements sandwiching a central, rotatable valve disc element, said disc elements being coaxially aligned and mounted on a spindle. One of the outer stationary elements has a first external loop secured thereto, said loop having a precise interior volume. An aspirator probe is secured to the other of said stationary elements. The central element has formed therein an axial segmenting passageway having a precise interior volume. A second external loop is secured to the center element. The second loop extends outwardly, preferably radially, of said element and has a precise interior volume. Appropriate interior passageways are provided in the outer elements for directing a liquid sample in a continuous path through the valve assembly, the path including the one segmenting passageway and the first and the second external loops.

Abstract: Bellows pump and actuating apparatus for automatically aspirating biological sample fluid material into and through an aspirating probe from a source of fluid sample material, into and through a sample segmenting valve for passage through a counting device. A plurality of bellows members, each having an axis of compression and expansion, has one end mounted on a fixed member. Timing and stroke members are provided for actuating movement of the other end of the bellows members, which are free to be moved parallel to their axis. A positioning member positions the timing and stroke members coaxially of the bellows members at preselected times. A drive member moves the timing and stroke members parallel to the axis of compression and expansion of the bellows members. Photo-optical indicating members, cooperating with the positioning member, interrupts the drive to the positioning member when the timing and stroke members are coaxially aligned with the bellows members.

Abstract: An improved procedure for statistically evaluating the performance, precision and/or accuracy, of at least one analytical instrument in a pool of like or substantially like instruments by comparing the performance of the one instrument located in one laboratory with the performance of like instruments in other laboratories. The procedure includes the step of quantitatively analyzing a reference or control specimen of known constituents by each instrument in the pool and collecting the resultant data from the one instrument in the pool and of the pool instruments. The mean data from the one instrument and of the pool instruments are mathematically correlated in a series of statistical equations for computing a novel, sensitive index known as the "Instrument Performance Index" or IPI.

Abstract: Water soluble xanthylium derivative substrates of rhodamine 110 and rhodol permit spectrophotometric and fluorescent measurements of trypsin-like enzymes without the addition of organic solvent additives and/or special water solubilizing agents. These novel substrates exhibit increased sensitivity for determining low levels of activity of trypsin-like enzymes such as proteolytic enzymes, cofactors, activators, antiactivators, and inhibitors. These substrates can be substituted for fibrinogen to monitor the pathways of blood coagulation.

Abstract: A circuit, which is useful to provide data needed to measure the electrical opacity of a particle, for instance a blood cell, passing through a Coulter type transducer, includes a current source for providing a conventional d.c. current through the sensing aperture of the transducer, as well as an oscillator for providing a high frequency current through the aperture. The oscillator includes an active device and a resonant circuit, and the aperture is coupled in parallel with the resonant circuit of the oscillator. The oscillator can be any type of oscillator, such as a Hartley oscillator. As a particle passes through the aperture, the resistance of the aperture increases, which in turn, increases the Q of the oscillator circuit, whereby the oscillator output signal is amplitude modulated in accordance with the increased Q. This amplitude modulated signal can be detected to provide a value based on the high frequency reactance of the particle being detected. The change in d.c.

Abstract: A debris detector for a particle counter, such as a blood cell counter, of the COULTER (R) type. When a particle, or transient debris, passes through the sensing orifice of the particle detector, a voltage pulse occurs; whereas, when debris lodges in or against the orifice of the particle detector, a d.c. voltage shift occurs. The voltage at the orifice is capacitively coupled to an amplifier and the output of the amplifier is integrated. The capacitor coupling the orifice voltage to the amplifier causes an undershoot voltage at the trailing edge of each particle or transient debris pulse, such that a zero average voltage is applied to and, hence, from the amplifier for each voltage pulse. The integrated voltage is applied to a voltage comparator to provide an output signal therefrom whenever the integrated voltage exceeds a reference voltage. The comparator output signal is provided to a delay circuit having a delay related to the time required for a particle to pass through the COULTER detector orifice.

Abstract: Apparatus for detecting contaminants, including emboli, in a blood sample prior to blood cell analysis, wherein fluid density sensors are arranged on opposite sides of a fluid segmenting valve to provide electrical signals indicative of the degree of optical opacity of the fluid flowing through the sensors. The derived signals are compared against a diluent reference level signal to provide resultant signal outputs indicating the presence or absence of emboili or other contaminants within the segmented portion of fluid.

Abstract: This invention describes a reagent system, including saponin in a lysing reagent and a rapidly active cross-linking agent such as glutaraldehyde as a fixing reagent, which reproducably affects whole blood to cause the red blood cells to stromatolyze and modifies the leukocytes to generate data to define four distinct clusters for detection and classification by flow analysis instrumentation. The clusters represent the four major leukocyte types found in blood: lymphocytes, monocytes, neutrophils and eosinophils, thus providing a method of leukocyte differential analysis. The parameters used for the leukocyte classification include combinations of two or more of DC (Coulter) volume, high frequency (RF) size, opacity (RF size/DC volume), light scatter at various angular ranges, and fluorescence at various wavelengths of illumination.

Abstract: Automatic printing apparatus wherein a single turnaround item-document is utilized as an initial source of intelligible information-data and thereafter by comparing certain of the data on the document with additional data inputted thereto by means of operably associated external hardware and subsequently summarizing the total data on the item effective to provide a final document including both the initially inputted information-data as well as the data resulting from the comparison and summarization.

Abstract: A slide motion sampling valve for use with a particle study device and carrying an expansive type microsyringe having a minimum trapped volume. The sampling valve is formed of a slidably movable member carrying a trapping volume, an expansive element and ejection port in the form of a fine aperture, and a stationary element sealingly engaged with said movable member and carrying an opening leading to the entrance of the sheath flow arrangement. The valve operates between a conditon where the ejection port and the opening are aligned and a condition where communication to the entrance is blocked whereby to isolate the trapping volume from said entrance except during ejection of the predetermined amount. One embodiment described employs a linear sliding motion while another embodiment employs a rotating sliding motion.

Abstract: This invention primarily is directed to a hematology reference control solution, the three separate white cell control portions thereof consisting of three types of fixed red cells of determined size distribution for checking the operation of a particle analyzing instrument, including its predetermined lower and upper threshold settings for each class or subclass of leukocytes.For preparing a human granulocyte analogue, nurse shark erythrocytes are altered and fixed in a chilled solution to simulate in number, size and distribution the granulocytes in human whole blood.