The stability of total nutrient admixtures (TNAs) prepared from dextrose and amino acid injections commercially packaged in a dual-chamber container and a safflower-soybean oil fat emulsion was studied. The admixtures studied were divided into two groups. Group 1 admixtures represented 14 combinations of Aminosyn II, dextrose, and Liposyn II. Group 2 admixtures represented 10 combinations of Aminosyn II with Electrolytes, dextrose, and Liposyn II. Amino acid concentrations of 7, 8.5, and 10%, dextrose concentrations of 10, 20, 40, and 50%, and 10 and 20% fat emulsion were used. After the amino acid and dextrose injections were mixed in their original container (Nutrimix, Abbott Laboratories), the fat emulsion was added. One of two combinations of electrolytes and trace metals was then added. Multivitamins were added to each TNA just before 24-hour storage at room temperature (25 +/- 4 degrees C). Admixtures were tested initially and at the conclusion of storage periods of 24 hours at room temperature or nine days at 5 degrees C followed by 24 hours at room temperature. Measurements of pH, emulsion particle size, and weight percent of oil particles larger than 5 microns in diameter (HIAC) were made after visual inspection of each admixture. In selected admixtures, concentrations of individual amino acids and dextrose were determined by chromatographic techniques initially and at the conclusion of storage. The TNAs retained a uniform milk-like appearance throughout both storage periods. The pH values, particle size, HIAC measurements, and amino acid and dextrose concentrations remained essentially unchanged.(ABSTRACT TRUNCATED AT 250 WORDS)