ADSORPTIVE VOLTAMMETRIC DETERMINATION OF MIXED PIGMENT BY ITERATIVE TARGET TRANSFORMATION FACTOR-ANALYSIS

Synthetic pigments, such as amaranth, sunset yellow, tartrazine and po nceau 4R, have sensitive adsorptive voltammograms in a phosphate buffe r (pH=5.7), The voltammetric waves of these pigments, however, are ser iously overlapped and it is difficult to determine them without a pres eparation. In this paper, the experimental conditions were investigate d, The mixture was accumulated for 240 s at a HMDE with a accumulate p otential, -100 mV, After a 10 s quiet time the potential was then scan ned from -100 to -1 100 mV using linear sweep voltammetry (LSV) with a scan rate, 100 mV/s, Tile voltammetric data of mixed pigments were pr ocessed by a chemometric approach, iterative target transformation fac tor analysis (ITTFA) and acceptable results with a total prediction er ror, 8.35%, were obtained.