Although
the absorbing strength at 742 nm is relatively lower than that at
555 nm, much higher selectivity at such wavelength can be
obtained at 742 nm because very few other metal complexes can
form with 5-Br-PADAP and generate absorbance. Based on the
above selectivity, the speciation of iron in beer sample using cloud
point extraction (CPE) coupled with direct spectrometric analysis
was reported. The method is simple (without digestion of beer),
reliable and more convenient than AAS combining UV–vis photometric
analysi