title: Solubility changes on mixing short- and long-acting insulin preparations.
abstract: The loss of solubility of short-acting insulins when mixed in a ratio of 1:1 with intermediate-acting insulins in vitro was determined using high-performance liquid chromatography. Insulin preparations (porcine and human) from three different manufacturers were tested and various times of mixing (0-24 h) were investigated. The loss of solubility with mixtures of human insulins and with mixtures of porcine Velosulin (Nordisk) and Insulatard (Nordisk) was small at all the times used. A mixture of porcine Actrapid MC (Novo) and Monotard MC (Novo) led to a 60-95% loss of the soluble component, depending on the duration of mixing. The greater the time the greater the loss. These in vitro data indicate that short-acting insulins may lose solubility when mixed with long- or intermediate-acting ones. This phenomenon could be clinically relevant when patients are changed from mixtures of monocomponent to human insulins.
authors.affiliation: Department of Pharmacology, University of the Witwatersrand, Johannesburg.
authors.forename: I
authors.initials: I
authors.lastname: Havlik
authors.forename: G
authors.initials: G
authors.lastname: Galasko
authors.forename: E
authors.initials: E
authors.lastname: Alberts
authors.forename: K I
authors.initials: KI
authors.lastname: Furman
authors.forename: H C
authors.initials: HC
authors.lastname: Seftel
mesh_terms: D004338:Drug Combinations; D006801:Humans; D007328:Insulin; D012995:Solubility; D013997:Time Factors
chemical_list: D004338:Drug Combinations; D007328:Insulin