Abstract: A stable reference solution for calibrating and monitoring blood gas instrumentation is disclosed. The solution comprises an aqueous mixture containing a hemoglobin solution derived from a mammalian source which comprises at least about 95% reduced hemoglobin. The solution additionally contains a metal catalyzed methemoglobin reducing system, reference concentrations of selected electrolytes and an organic buffer. To provide a control element having a variety of properties similar to fresh, whole, human blood, the reference solution is stored in a sealed ampule under an inert atmosphere containing CO.sub.2 until just prior to use. The ampule is subsequently opened and the solution is equilibrated with a gas mixture having components which provide gasses in a physiological range to the solution. The solution is characterized by exhibiting properties similar to fresh blood subsequent to equilibration and an extended storage life prior to equilibration.

Abstract: Methods for blood sample preparation using reagent compositions which include a zwitterionic surfactant for sphering of cells to eliminate orientational noise. When the reagent composition including a for staining a subset of cells is reacted with an anticoagulated blood sample, and the reaction mixture is passed through the sensing region of a flow cytometer, the light scattered and absorbed by each cell is measured, the stained cells can be distinguished from the unstained cells, and when the cells are reticulocytes and mature erythrocytes, respectively, the volume and hemoglobin concentration of each reticulocyte or erythrocyte, and the hemoglobin content, mean cell volume, mean corpuscular hemoglobin concentration, and mean cell hemoglobin of the reticulocytes or erythrocytes are calculated from the measured cell-by-cell volume and hemoglobin concentration.

Abstract: A calibration system comprising a sensor cassette including at least one sensor to be calibrated and a housing having a liquid passage including a chamber. The housing is coupled to the sensor cassette to place the liquid passage in fluid communication with the sensor cassette. The housing has a gas injection passage through which a gas can be injected into the liquid passage to mix with a calibration liquid in the housing. A gas vent vents the gas from the housing. Porous media is provided in the chamber. The gas and calibration liquid pass through the porous media, and the porous media assists in rapid mixing of the gas and the calibration liquid.

Abstract: The method of stabilizing a carbon dioxide sensor involves formulation of a bicarbonate buffer solution in the sensor with a bicarbonate ion concentration of from about 100 mM to about 200 mM bicarbonate. The method also involves treatment of the sensor to reduce the instability that may occur in carbon dioxide sensors when such sensors are exposed to either very low or very high carbon dioxide levels for extended periods of time. The sensor is treated by exposing the sensor to an aqueous solution containing at least 2 weight percent carbon dioxide, for from several days to several months. The solution may be prepared in advance, or may be dynamically infused with carbon dioxide to provide the desired carbon dioxide content.

Abstract: A method for producing a liquid phase substance having a pre-established concentration of CO.sub.2 suitable for calibrating analytical instruments such as hemogasanalyzers consists in:preparing an aqueous solution of precisely known strength of a water-soluble salt of carbonic acid,then transferring said solution to a flow reactor containing a cation exchange resin in hydrogenionic form,passing the aforesaid solution of carbonic acid salt through the aforesaid cation resin,thereby achieving the reaction of producing a pre-established quantity of CO.sub.2, andtransferring the eluate thus obtained directly to the analytical instrument for calibration.

Abstract: A precalibrated sensing system for determining a blood parameter such as the partial pressures of oxygen (pO.sub.2) and carbon dioxide (pCO.sub.2), and the negative logarithm of hydrogen ion activity (pH). A dry sensor is provided which may be calibrated in the factory, packaged, sterilized and stored, without requiring recalibration prior to use.

Abstract: A multi-phase control and/or calibration system consists of a liquid phase containing an amount of dissolved oxygen (O.sub.2) in which the O.sub.2 partial pressure is made relatively temperature insensitive over an ambient temperature range of interest, and an amount of dissolved carbon dioxide (CO.sub.2) and one or more solute species that provide temperature stability with respect to the partial pressure of CO.sub.2 over the ambient temperature range of interest. The liquid phase is in equilibrium with a vapor phase and the system sealed with a storage atmosphere.

Abstract: A method and system for controlling the concentration of one or more gaseous species of interest in a sample medium throughout a range of temperatures in which a temperature related, time variable dominant independent source of the gaseous species of interest is used to control the partial pressure of one or more gaseous species of interest contained in the sample medium in a manner such that the concentration of the gaseous species of interest in the sample medium remains essentially the same over the temperature range. The source of the gaseous species of interest comprises a reservoir containing an amount of a temperature sensitive source of the gaseous species of interest. The sample and the reservoir are contained in separate fluid-tight, gas-permeable enclosures further confined by a common substantially gas-tight enclosure.

Abstract: The solution for storage and calibration of an intravascular blood sensor is an aqueous solution of from 10-35 mM of a first buffer component of bicarbonate, and at least one additional buffer component selected to maintain the pH of the solution substantially at or slightly below a neutral pH, and preferably below approximately pH 8. The first and additional buffering components preferably are selected to act in two separate pH regions with substantially no overlap of the buffering capacity of the different buffering components, and the concentration of the first buffer component in the solution is selected to permit a two point calibration of the intravascular multiparameter blood sensor by carbon dioxide and oxygen gas tonometry.

Abstract: A pre-determined amount of solubilized reagent is reacted to release CO.sub.2 in a controlled-temperature reaction vessel and a controlled-pressure area adjacent the reaction vessel.

Abstract: The method of stabilizing a carbon dioxide sensor involves treatment of the sensor to reduce the instability that may occur in carbon dioxide sensors when such sensors are exposed to either very low or very high carbon dioxide levels for extended periods of time. This is accomplished by storing the sensor in an aqueous solution containing at least 2 weight percent carbon dioxide, for from several days to several months. The solution may be prepared in advance, or may be dynamically infused with carbon dioxide to provide the desired carbon dioxide content.

Abstract: An endless path calibration system comprising a sensor cassette having a flow-through passage and at least one sensor to be calibrated, a chamber coupled to the sensor cassette to define an endless path and a sterile calibration liquid in the endless path. A gas injection passage for injecting gas into the sterile calibration liquid and a gas vent leading from the endless path to the exterior of the endless path. A check valve allows gas to escape from the endless path and substantially prevents gas and liquid from entering the endless path through the gas vent.

Abstract: Hydrogen peroxide stabilized in the presence of blood components by the addition of a metal oxide oxidant, an anionic chelating agent, particularly hydroxylic carboxylate and nitroprusside, and a catalase inhibitor. The composition finds particular application for stabilizing hydrogen peroxide in a diagnostic assay on a bibulous support.

Abstract: Aqueous acidic ferrioxalate compositions are disclosed for use as calibrants of pCO2 and of PO2 after photodecomposition. Compositions with high iron(III) to oxalate molar ratios (e.g., 5:1 to 100:1 with 0.3 to 15 millimolar oxalate) produce carbon dioxide on exposure without oxygen consumption. Compositions with low iron(III) to oxalate ratios (e.g., 1:100 to 1:2000) with 0.1 to 5 millimolar iron(III) produce carbon dioxide on exposure with concurrent oxygen consumption. Use of the two types of compositions enables calibration values to be established with varying pCO2 values and with, respectively, high and low pO2 values.

Abstract: Electrodes for the measurement of pCO2 and/or pO2 are calibrated with an exposed aliquot of a calibration liquid. A constituent such as a ferrioxalate salt in the calibration liquid is converted to the gas in a reproducible concentration by exposure of the aliquot to light. In some instances, the calibration liquid is equilibrated with air prior to exposure. Some mechanisms of light generation of carbon dioxide also consume oxygen, so as to depress the pO2 value by a reproducible amount. The use of two different calibration liquids enables both one-point and two-point calibration of the Clark oxygen electrode and the Severinghaus pCO2 electrode of a blood gas instrument.

Abstract: An endless path calibration system comprising a sensor cassette having a flow-through passage and at least one sensor to be calibrated, a chamber coupled to the sensor cassette to define an endless path and a sterile calibration liquid in the endless path. A gas injection passage for injecting gas into the sterile calibration liquid and a gas vent leading from the endless path to the exterior of the endless path. A check valve allows gas to escape from the endless path and substantially prevents gas and liquid from entering the endless path through the gas vent.

Abstract: A stable reference solution for calibrating and monitoring blood gas instrumentation is disclosed. The solution comprises an aqueous mixture containing a hemoglobin solution derived from a mammalian source which comprises at least about 95% reduced hemoglobin. The solution additionally contains a bicarbonate buffer and a metal catalyzed methemoglobin reducing system and an organic buffer. To provide a control element having a variety of properties similar to fresh, whole, human blood, the reference solution is stored in a sealed ampule under an inert atmosphere containing CO.sub.2 until just prior to use. The ampule is subsequently opened and the solution is equilibrated with a gas mixture having components which provide gasses in a physiological range to the solution. The solution is characterized by exhibiting properties similar to fresh blood subsequent to equilibration and an extended storage life prior to equilibration.

Abstract: Aqueous solutions containing buffers and electrolytes are adjusted to levels required for calibration of both blood gas analyzers and ion selective electrolyte analyzers. A control material, composed of similar matrix, is adjusted to three levels of blood gas and electrolyte conditions. These quality control materials are used to monitor blood gas/electrolyte laboratory instrumentation.

Abstract: A liquid control standard for the use in the quality assurance of blood analysis instrumentation systems is disclosed. The liquid control standard is able to act as a control standard for blood gas instrumentation systems measuring pH, pCO.sub.2 and pO.sub.2 of blood, as a liquid control standard for ion selective electrode instrumentation systems for the measuring of electrolytes such as ionized calcium and total calcium as well as Na, K and Li ions in the blood and, optionally, as a control standard for a co-oximeter measuring the amount of total hemoglobin present in the blood and the relative amounts of other hemoglobin fractions present in the blood.

Abstract: Lysable, blood platelet controls are prepared by treating animal red blood cells larger than or within the size range of human blood platelets with a fixing agent for red blood cells for a time sufficient to partially rigidify the red blood cell membrane enabling shrinking to a permanently shrunk condition, subjecting distinct groups of said partially fixed red blood cells to hemolysis wiht a hemolytic agent to partially remove hemoglobin therefrom, the hemolysis of each distinct group of cells removing a different amount of hemoglobin, subjecting the resulting red blood cells to centrifugation to collapse the red blood cell membrane around the hemoglobin remaining in said cells, said distinct group of cells and the extent of hemolysis being selected so as to provide after said centrifugation a mixture of permanently shrunken lysable cells that simulate in number, size and volume distribution the platelets present in human whole blood.

Abstract: A packaged single-phase reference liquid comprising a gas and liquid-impermeable sealed container and a reference liquid containing a highly diffusible gas.

Abstract: A liquid control standard for the use in the qualilty assurance of blood analysis instrumentation systems is disclosed. The liquid control standard is able to act as a control standard for blood gas instrumentation systems measuring pH, pCO.sub.2 and pO.sub.2 of blood, as a liquid control standard for ion selective electrode instrumentation systems for the measuring of electrolytes such as ionized calcium and total calcium as well as Na, K and Li ions in the blood and, optionally, as a control standard for a co-oximeter measuring the amount of total hemoglobin present in the blood and the relative amounts of other hemoglobin fractions present in the blood.

Abstract: Perfluorocarbon emulsion formulations are oxygenated prior to use by means of a portable oxygenation system. The blood substitute is in a closed container or bag. An oxygen-containing gas is introduced into the bag from a separate container. The bag is continuously agitated for a sufficient time to increase the pO.sub.2 of the perfluorocarbon emulsion formulations to a desired pressure, e.g., to at least 600 mmHg. In one embodiment, the system used for oxygenation of the perfluorocarbon emulsion formulations comprises a small tank for gas having an inlet port and an outlet port fitted with shut-off valves. The outlet port is adapted to be connected to a filter which, in turn, is adapted to be connected to the inlet port of a three-way valve. The primary outlet of the three-way valve is adapted to mount a hypodermic needle which is adapted to be pushed through a rubber septum in a port of the bag to communicate with the interior of the bag.

Abstract: This invention discloses a multiple control standard for the use in the quality assurance of blood analysis instrumentation systems. The liquid control standard is able to act as a control standard for blood gas instrumentation systems measuring pH, pCO2 and pO.sub.2 of blood, as a control standard for a co-oximeter measuring the amount of total hemoglobin present in the blood and the relative amounts of other hemoglobin fractions present in the blood, and as a liquid control standard for ion selective electrode instrumentation systems for the measuring of electrolytes such as Na, K, Li and Ca ions in the blood.

Abstract: This invention discloses a multiple control standard for the use in the quality assurance of blood analysis instrumentation systems. The liquid control standard is able to act as a control standard for blood gas instrumentation systems measuring pH, pCO2 and pO.sub.2 of blood, as a control standard for a co-oximeter measuring the amount of total hemoglobin present in the blood and the relative amounts of other hemoglobin fractions present in the blood, and as a liquid control standard for ion selective electrode instrumentation systems for the measuring of electrolytes such as Na and K ions in the blood.

Abstract: The present invention relates to aqueous perfluorocarbon emulsions and particularly microemulsions, and to their use as blood gas controls and calibrators.

Abstract: A blood gas-hemoglobin analysis control which simulates whole human blood characteristics comprising a buffered suspension medium containing erythrocytes which have been stabilized with an imidoester protein cross-linking agent while being contacted with a gas consisting of pure oxygen or pure carbon monoxide.

Abstract: This invention relates to the field of clinical controls useful for calibrating clinical chemistry analyzers and in manual testing methods, as well as clinical standards and reagents. In addition, it relates to methods for producing stabilized liquid clinical control, standards, and reagents.

Abstract: Cell useful for equilibrating a hydrophilic liquid such as an aqueous solution held therewithin with a gas composition. The cell comprises a tube having an open end and a closed end, the closed end comprising a porous member having a hydrophobic surface, the member being impervious to flow of a hydrophilic liquid therethrough when the tube is filled therewith and positioned vertically with a closed end thereof downwardly and being permeable to pressurized flow of the gas composition upwardly therethrough. The invention is also concerned with such a cell in an apparatus for equilibrating a hydrophilic liquid such as an aqueous solution with a gas composition, which apparatus comprises a gas vessel having therewithin a gas of a selectable composition at a pressure above ambient atmospheric pressure, flow control means for receiving flow from said vessel and controlling a flow rate therefrom and conduit means leading from the flow control means to a solution cell having therewithin a hydrophilic liquid.

Abstract: The invention is concerned with apparatus for equilibrating an aqueous solution with gas. The apparatus includes a gas vessel having therewithin a gas of a selectable composition at a pressure above ambient atmospheric pressure. Flow control means receive flow from the vessel and control a flow rate therefrom. A solution tube is provided having an aqueous solution therewithin. Conduit means lead from the flow control means to the tube below a liquid level of the aqueous solution. Means are also provided for causing the gas to be delivered within the aqueous solution below the liquid level as a plurality of bubbles. The process of the present invention is directed at simultaneously equilibrating a plurality of aqueous solutions each with one of a plurality of gas compositions.

Abstract: A tonometer having vessels for producing and maintaining multi-levels of tonometerd aqueous buffered solutions and whole blood available for use in the quality controlling of a blood-gas analyzer. A water bath maintains all vessels at a predetermined temperature and gas mixtures are supplied at a very low rate thereby permitting continuous operation of the tonometer.

Abstract: Blood gas control containing hemoglobin, a pH buffering agent, and a reduced pyridine nucleotide capable of participating in a reaction which reduces methemoglobin to normal hemoglobin.

Abstract: A reference fluid for the calibration and control of blood gas instruments is comprised of substantially pure stroma-free hemoglobin solution, a buffering agent, a source of bicarbonate ion and predetermined amounts of gases found in in vivo blood.

Abstract: Cutaneous methods for measurement of substrates in mammalian subjects are disclosed. A condition of the skin is used to measure a number of important substances which diffuse through the skin or are present underneath the skin in the blood or tissue. According to the technique, an enzyme whose activity is specific for a particular substance or substrate is placed on, in or under the skin for reaction. The condition of the skin is then detected by suitable means as a measure of the amount of the substrate in the body. For instance, the enzymatic reaction or by-product of the reaction is detected directly through the skin as a measure of the amount of substrate. Polarographic electrodes or enzyme electrodes are employed as skin-contact analyzers in the transcutaneous measurement of oxygen or hydrogen peroxide to quantitatively determine blood substances such as glucose and alcohol. In a preferred quantitative technique, the skin is arterialized, i.e.

Abstract: Disclosed are cell-free, stable, aqueous blood gas controls containing a proteinaceous foaming agent. The addition of foaming agent to the blood gas control permits generation of a gas impermeable foam within the head space of a sealed ampule in which the control is packaged. Upon agitation of the ampule prior to opening, the foam thus generated effectively isolates the control fluid from the ambient environment, thereby maintaining the concentration of gases dissolved within the fluid at their assigned values.

Abstract: A lysable, blood platelet reference control comprising a suspension of a mixture of permanently shrunken animal red blood cells in a suspension medium non-deleterious to said cells, said cells having been partially fixed with a fixing agent to reduce cell membrane elasticity prior to being shrunken, and said mixture of permanently shrunken cells in said suspension medium simulating in number, size and volume distribution the platelets present in human whole blood.

Abstract: A method and system for measuring the oxygen carrying capacity of normal and abnormal hemoglobins and red cells under controlled pH, ionic strength, temperature and gas conditions is described. A blood sample and a physiologically balanced medium are placed in a cuvette and means are associated therewith for measuring the fractional saturation of the sample and the partial pressure of the oxygen (sometimes referred to as the oxygen tension) and provide output signals to an X-Y plotter for continuous recording. Preferably, means for maintaining the temperature of the medium and the blood sample is provided.

Abstract: A chemical seal for isolating the liquid phase of a contained liquid from the vapor phase present in the container headspace comprises a chemically impregnated gel formed by mixing a biopolymer gel, a high molecular weight polymer and chemical impregnants with water to form a gel-forming aqueous solution which is applied to the surface of the contained liquid and allowed to solidify thereby forming a mechanically stable, chemically impregnated gel seal in intimate contact with the contained liquid.

Abstract: Biological cell compositions are stabilized to preserve aldehyde functionality by formation of acetal, particularly cyclic acetal, primarily in order to prevent cell-to-cell crosslinking. The stabilized biological cells are particularly useful as human blood particle analogs in reference reagents employed in electronic hematology testing instrumentation.A process for preparing the acetal-stabilized biological cells employs reaction of polyaldehyde-treated biological cells with alcohol, preferably including 1,2 dialcohol, under acidic conditions; thereafter, the resulting product solution is adjusted to basic condition, stabilizing the acetal formation on the biological cells.