Column preconcentration and second derivative spectrophotometric trace determination of scandium in standard biological and synthetic samples using 1-(2-thiazolylazo)-2-naphthol

Scandium has been preconcentrated from a large volume of its aqueous solution after solid phase extraction of its 1-(2-thiazolylazo)-2-naphthol chelate onto ammonium tetraphenylborate-naphthalene adsorbent in the pH range 4.0 - 5.8. The solid mass consisting of metal complex along with the adsorbent was dissolved in 5 ml of DMF and quantified by second derivative spectrophotometry. The calibration graph is linear in the concentration range 0.08-2.8 mu g ml(-1) with a correlation coefficient of 0.9998. The sensitivity of the method as found from the slope of the calibration plot is 0.185 (d(2)A/d lambda(2)) ml mu g(-1) Nine replicate determinations of 7.0 mu g of scandium in 5 ml of final DMF solution give second derivative amplitudes as 0.255 with a relative standard deviation of 0.92%. The various instrumental and experimental variables are optimized. The conditions developed have been utilized for its determination in various standard and synthetic samples. The proposed method is found to be reproducible, reliable, sensitive, selective and economical.