3.2. Optimization of the SALLE procedure
The main factors affecting the extraction efficiency in a SALLE
procedure, such as the type and volume of the organic solvent,
sample volume, type and amount of salt, pH of the sample and
vortex time, were evaluated by mean of recovery studies.
Efficiency was evaluated by means of the recoveries of the
extraction process, estimated as the peak area ratio of the analytes
fortified before and after the application of the SALLE procedure.
All the experiments for the optimization process were performed
in triplicate (n¼3) by spiking ultrapure water with 100 mg/L of a
mixed standard solution containing nine SUHs.