摘要:
A droplet travel path monitoring mechanism for a flow cytometer is operative to adjust the droplet break-off point back to an initially calibrated spatial location, in the event of the departure from calibrated timing of gaps in the unsorted fluid droplet stream that have been created by the deflection of charged droplets. In addition, the flow cytometer is operative to monitor prescribed characteristics of deflected droplet streams, and to controllably adjust drop sorting deflection parameters, so as to maintain the deflected travel path of sorted droplets coincident with the opening into a sorted droplet collection container, thereby maximizing collection of all sorted droplets.
摘要:
An improved isotonic multipurpose blood diluent, and a method for use of this diluent are provided. The diluent is especially suitable for electronic enumeration and sizing of blood cells, determination of hemoglobin parameters and differentiation of leukocyte subpopulations in a single blood cell sample using a cyanide free lytic reagent. The diluent finds particular applicability over wide operating temperatures.
摘要:
A method is disclosed which allows more accurate counting of particles where the sample has significant size variability between particles. The method uses flight time (44) and wait time (22) to obtain a corrected count of particles (12).
摘要:
A stable protein-coated nickel particle useful in biological assays contains a nickel particle having removed from the surface thereof nickel oxide; a linker attached to said nickel particle, the linker having a free amino group; and a protein attached to said linker by covalently bonding to the free amino group. Methods of producing and using these oxide-free nickel-protein conjugates are disclosed.
摘要:
A method for analyzing an abnormal particle population in an experimental sample containing particles which involves a particle property distribution index based on an average particle property (e.g., size) distribution curve (10) for multiple normal samples in a particle analysis instrument. The process involves producing an experimental particle property distribution curve by analyzing an experimental sample containing particles in the instrument. The distribution curve of the experimental sample is analyzed to identify particle populations at the lower (14) or upper (18) region of the experimental distribution curve that differ from particle populations in the regions of an average particle property di stribution curve. Thereafter, the number of particles within the lower or upper region of the experimental distribution curve that differs from the average curve is determined and employed for diagnosis of a relevant characteristic of the particle population. A computer program which makes calculations for such methods can be employed or can be integrated into a particle analysis instrument. The method, program, and instruments of this invention provide a novel red blood cell parameter.
摘要:
A method of analyzing the concentration of soluble analyte in a sample involves performing a competition assay using a predetermined amount of formed bodies to which are attached at least one analyte, varying known concentrations of an unlabeled ligand that binds to said analyte, and a known concentration of said ligand labeled with a detectable marker. After analysis in a flow cytometer, the test sample and a plurality of control samples generate data used for determining the concentration of the soluble analyte in the sample.
摘要:
Apparatus for precisely aspirating small volumes of liquid, e.g., a blood sample, contained in a vessel, e.g., a test tube or vial, includes a mechanism for sensing that the tip of an aspirating probe is contacting the bottom of the vessel during the aspiration process. Such a bottom-sensing mechanism is adapted to sense a predetermined forcible interaction between the probe tip and the vessel bottom. In a preferred embodiment, such forcible interaction is sensed by detecting movement of a movably mounted platform that supports the vessel during aspiration. In a second embodiment, the forcible interaction is sensed by detecting the back-emf in a motor winding used to advance the aspiration probe.
摘要:
An open/close valve construction for use in solid-state fluid transport circuits having discrete fluid passageways (12a, 13a, 20) formed in rigid substrates (53, 56, 57) with a substrate land (58) between port regions of the fluid passageways. The valve construction comprises a diaphragm disk (60) having a dome portion overlying the substrate land (58) and port regions and having a self-restoring resilience sufficient to maintain its dome configuration against substantial line vacuum. A valve actuator (21) is located above the dome portion and spring biased (22) to compress the dome into a flat configuration closing the port regions. Means for negating the spring force are provided to allow the dome portion to restore its configuration and open the valve.
摘要:
A method is provided for differentiation of nucleated red blood cells. In addition, the method provides for a concurrent differentiation of leukocytes in a blood cell sample by suitable electronic and optical measurements. The method includes exposing a blood cell sample to a reagent system to lyse mature red blood cells and subsequently analyzing nucleated red blood cells in a flow cell by optical analysis. A concurrent differentiation of nucleated blood cells and leukocytes can be performed using electronic and optical analysis. The electronic and optical analysis includes light scatter and impedance measurements. This method eliminates the use of nuclear stain for identification of nucleated red blood cells. The method of the present invention, for the first time, reports differentiation and enumeration of nucleated red blood cells without using fluorescence.