Separation of pharmaceutical products with reverse micelles

Reverse micelle extraction has received considerable attention in recent years due to its ability to\nselectively solubilise solutes from an aqueous phase and to maintain their biological activities.\nThis paper presents the results from studies on extraction of penicillin G from aqueous solution\n(forward extraction) and from reverse micelles to a new aqueous solution (backward extraction), by\nemploying the principle of liquid-liquid extraction with reverse micelles. AOT is used as a\nsurfactant and isooctane is used as an organic phase. The effect of pH, salt concentration, AOT\nconcentration, and initial penicillin concentration on the penicillin forward and backward transfer at\n21ºC was studied. The results show that the solubilisation of penicillin in the forward extraction is\ndependent on both pH and surfactant concentration. The backward extraction is dependent on\nionic strength, surfactant concentration and the initial amount of penicillin in the organic phase\nbefore backward extraction. Despite successful results in the backward extraction, the overall\nextraction yield of penicillin is found to be less than the initial amount of penicillin before forward\nextraction due to difficulties during the forward extraction process.