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US 4,304,672 AGranted
Stored blood and liquid system pH control method and apparatus
AssigneeSBR Lab, Inc.
InventorJohn P. McCue
Life of this patent
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AssigneeSBR Lab, Inc.
InventorJohn P. McCue
Estimating the term…
Method and apparatus for continuous pH control of aqueous liquid systems, particularly biological and biochemical systems such as stored blood, by sorption of H.sup.+ andwith a passive ion acceptor material isolated from, but in contact with liquid of said system in a selectively permeable membrane packet. Liquid systems of interest are those with an initial pH in the range of from about 4.5 to 9.0, and the pH of the system is maintained by the invention at its initial value, or brought within, and maintained in, the range of from about 6.5 to 8.0. The ion acceptor material is selected from an inorganic, relatively water insoluble metal oxide, hydroxide, phosphate or silicate matrix, which matrix is capable of maintaining a quasi-equilibrium pH state with the aqueous liquid system. The matrixing metals are preferably selected from Ti, Al and B. The matrices may be doped with oxides or hydroxides of Mg, Ca, Zn, Fe, Cu, Co, Cr and V to permit predetermined selection of a desired quasi-equilibrium pH value, and to adjust effective base capacity. Cation (e.g., Na.sup.+ and K.sup.+) doping may be used to expand the matrix lattice structure and help maintain electric (ionic) neutrality. Typical matrix acceptor compounds are selected from Al.sub.2 O.sub.3, anhydrous Al(OH).sub.3, Al(OH).sub.3 gel (preferred), MgHPO.sub.4, and Mg.sub.2 Si.sub.3 O.sub.8.
An ion acceptor packet unit used for pH control of aqueous liquid systems containing ions selected from water soluble bases, water soluble acids, and mixtures thereof comprising in operative combination:
In a method for continuously maintaining the pH of liquid stored mammalian blood subject to deterioration through cumulative metabolic acidosis, within a very narrow pH range of 7.0 to 7.2 for period of time ranging to at least 21 days, the steps of mixing said mammalian blood with an anticoagulant plasma medium and continuously maintaining the temperature of said blood plasma mixture within the range of 4.degree. to 7.degree. C., while maintaining contact of said blood mixture with a dialysis membrane in permeable communication with a hydrogen ion acceptor in the form of a dilute saline solution having dispersed therein a solid hydrogen ion acceptor material selected from the group comprising aluminum hydroxide gel, anhydrous aluminum hydroxide, aluminum oxide, and mixtures thereof, the rate of hydrogen ion acceptance of said acceptor medium being substantially equivalent to the rate of generation of hydrogen ions by said stored blood mixture.
Liquid storage means for maintaining the pH of biological and biochemical liquid systems subject to deterioration through cumulative metabolic acidosis, within a very narrow pH range from 7.0 to 7.2, for periods of time not less than 21 days, comprising:
Method of producing an ion acceptor material packet for control of pH of liquid systems having initial pHs in the range of from 4.5 to 9.0 comprising the steps of:
A method of controlling the pH of whole blood during storage comprising the steps of:
Dependencies are inferred from the claim text.