A comprehensive and suitable method for determining major ions from atmospheric particulate matter matrices.

The present study proposes an analytical methodology that employs ion chromatography-conductivity detection for simultaneous quantification of inorganic (F(-), Cl(-), NO(3)(-), SO(4)(2-), and PO(3)(-)), monocarboxylate (HCOO(-), CH(3)COO(-), propionate, n-butyrate, lactate, and pyruvate), dicarboxylate (oxalate and succinate), and tricarboxylate anions (citrate), as well as crustal cations (Li(+), Na(+), K(+), NH(4)(+), Ca(2+), Mg(2+)) at low pgm(-3) range in airborne particle samples in one single run. The optimized conditions for anions were as follows: 0.6 mmol L(-1) KOH for 0-14 min, 0.

Development of method for the speciation of inorganic iron in wine samples.

In this paper, we proposed a procedure for the determination of iron(II) and total iron in wine samples employing molecular absorption spectrophotometry. The ligand used is 2-(5-bromo-2-pyridylazo)-5-(diethylamino)-phenol (Br-PADAP) and the chromogenic reaction in absence or presence of ascorbic acid (reducing agent) allows the determination of iron(II) or total iron, respectively. The optimization step was performed using a multivariate technique (Box Behnken design) involving the factors pH, acid ascorbic concentration and reaction time.