4. Conclusion
An on-line cloud point extraction system was successfully applied
to the determination of Mn in food samples by detection using FAAS.
All steps of the procedure of the cloud point extraction were carried
out on-line, which allowed some advantages in relation to the cloud
point extraction in batch. Among these advantages is higher analysis
speed because some of the operations in batch procedures were not
necessary in the proposed system, such as incubation time, centrifugation,
cooling, removal of supernatant and dilution. The removal of
these steps significantly decreased the time of analysis. Other
advantages obtained by the proposed procedure are simplicity of
operation, low cost, lower consumption of samples and reagents, and
reduced losses of the analyte and risk of contamination. The
procedure developed showed good precision, accuracy and sensitivity
for the determination of Mn in food, and the results agree with those
obtained by ETAAS.