Extraction of aminoglycoside antibiotics with reverse micelles

Abstract

The reverse micelle system of sodium di-2-ethylhexyl phosphate was used to extract aminoglycoside antibiotics, neomycin and gentamicin. The aminoglycosides can be efficiently extracted into a reverse micelle solution, and the antibiotics extracted into the micelle phase can readily be recovered back to a divalent cation aqueous solution, such as Ca2+. The transfer efficiency, %E, is heavily dependent on pH and salt concentration in the aqueous feed solution. %E decreases drastically with pH in the pH range 8.5-11, and declines with increasing (NH&SO, concentration. A simple transfer mechanism was proposed which suggests that the antibiotic molecules were extracted into the inner water cores of reverse micelles through attractive electrostatic interaction during forward transfer. In backward transfer, the antibiotics loaded in the micelle phase are released back to an aqueous phase through breaking up of the reverse micelles by using divalent cation solutions. The model is supported by the results of dynamic light scattering and infra-red spectroscopy study.

The Development of Ring Rolling Technology - Part 2: Investigation of Process Behaviour and Production Equipment

“…The results are compared against the experimental results from Mamalis [22] and achieves good results given the coarseness of the mesh -the spread is generally overestimated at higher reductions. Hu et al [120] use this approach to simulate the hot forming of a titanium ring. In this case an elastoplastic material law is used and the guide rolls are modelled to control the roundness of the ring.…”

Phase Behavior of Mixtures Containing Antibiotics. Chloramphenicol Partitioning

“…However, some highly water-soluble antibiotics (e.g., streptomycin) require ion-exchange separation (Bartels et al, 1958). In addition, a new extraction process based on reverse micelles was recently proposed by Hu and Gulari (1996) for neomycin and gentamycin.…”

Reverse Micelle Liquid-Liquid Extraction of a Pharmaceutical Product

“…Previous studies on protein extraction have also shown that pH plays important role in reverse micellar systems [8,12,30,31,[35][36][37][38]. Noble and Varley [39), using protein as the biomolecule, pointed out that the pH of the protein and surfactant solutions could be manipulated so that the protein would exhibit a net charge opposite to that of the surfactant, thus allowing electrostatic interactions between the protein and surfactant in the different phases.…”

“…Separation processes using reverse micelles are based on conventional liquid-liquid extraction techniques. They are easy to scale up, have a high efficiency, can be made selective, have a Iow energy demand, and can be operated continuously [7,8,[10][11][12][13][14]. They can also offer moderate thermal conditions for processing of biomaterials [5,9).…”