Green Nanoemulsion Water/Ethanol/Transcutol/LabM-Based Treatment of Pharmaceutical Antibiotic Erythromycin-Contaminated Aqueous Bulk Solution.

Abstract

Contaminated wastewater released from hospital, domestic, and industrial sources is a major challenge to aquatic animals and human health. In this study, we addressed removal of erythromycin (ERN) from contaminated water employing water/ethanol/Transcutol/Labrafil M 1944 CS (LabM) green nanoemulsions as a nanocarrier system. ERN is a major antibiotic contaminant harming aquatic and human lives. Green nanoemulsions were prepared and evaluated for size, size distribution (measuring polydispersity index), stability, zeta potential, refractive index, and viscosity. Transmission electron microscopy (TEM) was used to visualize morphological behavior. The treated-water was analyzed for ERN by the spectroscopy, scanning electron microscopy-energy-dispersive X-ray analysis mode (SEM-EDX), and inductively coupled plasma-optical emission spectroscopy (ICP-OES) techniques. We studied factors (composition, size, viscosity, and time of exposure) affecting removal efficiency (%RE). The obtained green nanoemulsions (ENE1-ENE5) were stable and clear (<180 nm). ENE5 had the smallest size (58 nm), a low polydispersity index value (0.19), optimal viscosity (∼121.7 cP), and a high negative zeta potential value (-25.4 mV). A high %RE value (98.8%) was achieved with a reduced size, a high water amount, a low Capryol 90 content, and optimal viscosity as evidenced by the obtained results. Moreover, contact time had insignificant effect on %RE. UV-vis spectroscopy, SEM-EDX, and ICP-OES confirmed the absence of ERN from the treated water. Conclusively, ERN can easily be removed from polluted water employing green nanoemulsions prepared from the optimized excipients, and evaluated characteristics.