Abstract: A solid, water-soluble substantially anhydrous, storage-stable reagent formulation for use in conducting a clinical diagnostic test on a biological specimen is provided. The reagent formulation comprises a mixture containing a reagent capable of participating in a test reaction to effect a measurable change in a test system; and a nitrogen bearing polyoxyalkylene nonionic surfactant. The surfactant has a structure corresponding to that obtained when ethylene diamine is reacted sequentially with propylene oxide and ethylene oxide in the presence of a catalyst. The polyoxypropylene chains of said surfactant have an average molecular weight of between about 750 and about 6750. Methods of preparing the reagent formulations and methods of using them to conduct clinical diagnostic tests are also provided.

Abstract: Glutamic oxaloacetic transaminase and glutamic pyruvic transaminase are determined using granular water-soluble substantially anhydrous, storage stable reagent formulations comprising a nitrogen-containing polyoxyalkylene nonionic surfactant obtained by the sequential reaction of ethylene diamine with propylene oxide and ethylene oxide in the presence of a catalyst. The surfactant contains, polyoxypropylene chains having an average molecular weight of between about 750 and about 6,750 and polyoxyethylene chains constituting between about 10 and about 80 weight percent of the surfactant. The surfactant has an advantageous effect upon granulation, dissolution and storage stability of the anhydrous reagent formulations, and is effective for solubilizing proteins.

Abstract: Glucose is assayed in biological specimens using granular, water soluble, substantially anhydrous, storage-stable reagent formulations containing enzymes, a chromogen and/or a buffer and a nitrogen - containing polyoxyalkylene nonionic surfactant obtained by the sequential reaction of ethylenediamine with propylene oxide and ethylene oxide in the presence of a catalyst. The surfactant contains polyoxypropylene chains having an average molecular weight of between about 750 and about 6,750, and polyoxyethylene chains constituting between about 10 and about 80 weight percent. The surfactant has an advantageous effect on granulation, dissolution and storage stability of the reagent formulations and is effective for solubilizing protein such as enzymes.

Abstract: A solid, water-soluble substantially anhydrous, storage-stable reagent formulation for use in conducting a clinical diagnostic test on a biological specimen is provided. The reagent formulation comprises a mixture containing a reagent capable of participating in a test reaction to effect a measurable change in a test system; and a nitrogen bearing polyoxyalkylene nonionic surfactant. The surfactant has a structure corresponding to that obtained when ethylene diamine is reacted sequentially with propylene oxide and ethylene oxide in the presence of a catalyst. The polyoxypropylene chains of said surfactant have an average molecular weight of between about 750 and about 6750. Methods of preparing the reagent formulations and methods of using them to conduct clinical diagnostic tests are also provided.