Analytical sorbent and method of use

A method of preparing an analytical sorbent for an in vitro diagnostic test which has a stabilized sorbent capacity for endogenous material found in a body fluid selected from the group consisting of protein-type constituents and metals comprising:

• a. wetting a particulate inorganic crystalline lattice material with a standard aqueous saline solution, said particulate inorganic crystalline lattice material being selected from the group consisting of carbonates, phosphates, oxides, hydroxides, silicates, aluminates, and sulfates of the metallic elements in Groups IA, IIA, IIIA, IIB and VIII of the Periodic Table and mixed salts thereof;
• and
• b. heating the resulting dispersion at a temperature of from about 25.degree. C to the boiling point of said standard aqueous saline solution for a sufficient time to cause the sorbent capacity of said material to stabilize.

A method for preparing an analytical mixture containing a sorbent, for use in vitro diagnostic test which has a stabilized sorbent capacity for endogenous material found in a body fluid selected from the group consisting of protein-type constituents and metals, said mixture including an aqueous medium consisting essentially of an aqueous buffer solution and a particulate inorganic crystalline sorbent material selected from the group consisting of carbonates, phosphates, oxides, hydroxides, silicates, aluminates and sulfates of the metallic elements in Groups IA, IIA, IIIA, IIB and VIII of the Periodic Table and mixed salts thereof comprising:

• a. admixing said aqueous buffer solution and said sorbent and thereafter heating the mixture at a temperature in the range of from about 25.degree. C to the boiling point of said aqueous buffer solution until the percent uptake of said analytical sorbent for said endogenous material will not vary greater than about .+-. 1.5 percent;
• and
• b. packaging the mixture of aqueous buffer solution and said stabilized sorbent material in a sealed container.

A packaged analytical mixture within a sealed container comprising a sorbent for use in an in vitro diagnostic test which has a stabilized sorbent capacity for endogenous material found in a body fluid selected from the group consisting of protein type constituents and metals, said mixture including an aqueous buffer solution containing a particulate inorganic crystalline sorbent material selected from the group consisting of carbonates, phosphates, oxides, hydroxides, silicates, aluminates and sulfates of the metallic elements in Groups IA, IIA, IIIA, IIB and VIII of the Periodic Table and mixed salts thereof, said sorbent having been stabilized by a process comprising mixing said sorbent with an aqueous fluid consisting essentially of water and thereafter heating the resulting mixture at a temperature in the range of from about 25.degree. C to the boiling point of said water for a sufficient time to cause the sorbent capacity of said material for said endogenous material to stabilize.

A material for receiving and sorbing protein-type material in a clinical test procedure comprising an aqueous barbital buffer solution having dispersed therein a particulate inorganic crystalline lattice material selected from the group consisting of carbonates, phosphates, oxides, hydroxides, silicates, aluminates, and sulfates of the metallic elements in Groups IA, IIA, IIIA, IIB and VIII of the Periodic Table, and mixed salts thereof, which has been heated to a temperature of from about 25.degree. C to the boiling point of said solution for a sufficient time to cause the sorbent capacity of said material to stabilize for said protein-type material.

A method of treating a particulate inorganic crystalline lattice material selected from the group consisting of carbonates, phosphates, oxides, hydroxides, silicates, aluminates and sulfates of the metallic elements in Groups IA, IIA, IIIA, IIB and VIII of the Periodic Table, and mixed salts thereof, comprising wetting said material with an aqueous barbital buffer solution and thereafter heating the wetted material at a temperature of from about 25.degree. C to the boiling point of said barbital buffer solution for a sufficient time to cause the sorbent capacity of said material to stabilize.