An Investigation of the Reuse of Liquid Membranes and the Use of a Multidrug Donor Phase in Solute Transport

Abstract

Complex or multiple emulsions have been investigated for their potential use in pharmaceutics as both drug delivery and drug removal systems. Studies involving previously unused emulsions and single drug donor phases have been described in the literature. The subsequent uptake of solutes using one multiple emulsion or liquid membrane and the co-uptake of solutes from one donor phase were studied. The ability of liquid membranes to remove one solute following removal of another solute was studied for three systems using salicylic acid and phenobarbital at various temperatures. In each case it was observed that the liquid membrane was capable of subsequent drug uptake to varying degrees indicating that the previous use of liquid membranes does not materially affect their further use as sinks. The removal of two drugs from one donor phase using a liquid membrane was studied using acetylsalicylic acid, salicylic acid, and phenobarbital. These systems demonstrated the ability to remove two solutes simultaneously at rates which were of the same magnitude as those measured in single solute systems. The solute combination, initial molar concentration of each solute, and the liquid membrane oil/water ratio were found to influence the apparent rate constants and extent of removal for each drug in the donor phase.