Supported liquid membrane extraction of glyphosate metabolites

Use of the supported liquid membrane (SLM) technique for (aminomethyl)phosp honic acid (AMPA) extraction is presented. For the extraction of this analy te a suitable SLM system involves a liquid membrane containing Aliquat 336 - a cationic carrier that facilitates AMPA transport. The extraction of thi s compound, as in the case of glyphosate, is dependent on the donor phase p H and the concentration and type of counterion in the acceptor phase, altho ugh some differences are also observed. In both cases the transport mechani sm is counter-coupled transport in which the driving force of mass transpor t over the membrane is created by the gradient of chloride anions from the acceptor to donor phase.