Influence of copper, iron, and zinc on the physicochemical properties of parenteral admixture.

A parenteral admixture composed of 25% of 20% Intralipid, 25% of Azonutril 25, 37.5% of 30% Glucose and 12.5% of 50% Glucose was supplemented with copper, iron and zinc in the organic (gluconate) or inorganic (chloride) form at the following usual final concentrations: copper 0.24 mg/L, iron 0.50 mg/L, zinc 2.00 mg/L. The mixture was stored at 4 degrees C and at 25 degrees C for 24, 48, and 72 hours, and for one week. Determination of the pH indicated good stability of the mixture containing the trace elements in the gluconate form. A significant decrease in the pH of the mixture containing the trace elements as chlorides was noted after one week of storage at both temperatures. Particle size analysis revealed no significant variations between the two formulations after one week of storage. Flocculation kinetics confirmed the results obtained with the other two methods used to determine physicochemical stability. In addition, the kinetics indicated that the possibilities of coalescence processes are highly reduced in all cases. It may be concluded that the two type of mixtures remain stable for Seven days at 4 degrees C and 25 degrees C. However, mixtures containing trace elements in gluconate form should be chosen in cases of longer storage.