The pharmaceuticals pass sewage treatment plants. They like estrogen conjugates may cause problems. Drugs of the research were common, present in the aquatic environment and inability to be adequately removed by sewage treatment plants. There were seven different drugs in the research. Dibutyl sebacate and oleic acid formed liquid cores in capsules because they do not diffuse away from capsules and have affinity for drugs. Capsule external diameters were 740 µm and 680 µm and internal diameters were 570 µm and 500 µm. Agitation was 300 rpm. Equilibrium times were 30, 50 and 90 minutes.
Since dibutyl sebacate and oleic acid were different affinity for drugs, they were used concurrently. Four drugs were extracted effectively for 40–50 minutes (at least 50% removed). Extraction rates did not change significantly above 150 rpm. Membrane thickness did not affect the result significantly. On the contrary the capsule size was remarkable for mass transfer.