DERIVATIVE SPECTROPHOTOMETRIC DETERMINATION OF COPPER(II) IN NONIONICMICELLAR MEDIUM

A photometric method for trace analysis of Cu(II) with 1-(2-pyridylazo )-2-naphthol (PAN) in presence of a neutral surfactant, Triton X-100, has been reported in normal and derivative modes. The molar absorption coefficient (epsilon) and Sandell's sensitivity (S) of PAN-Cu(II) com plex at 555 nm is 5.21 x 10(4) mol(-1) cm(-1) and 1.22 ng cm(-2) respe ctively. The detection limit of Cu(II) is 4.0 ng ml(-1) and Beer's law is obeyed in the range 0.08-4.00 mu g ml(-1) of the analyte. Copper c ontent of a number of commercially available alcoholic beverages, biol ogical and standard alloy samples is reported. The results obtained ar e in excellent agreement with those obtained using AAS. (C) 1997 Elsev ier Science B.V.