determination of the stability constant of cobalt (іі) – piroxicam complex by spectrophotometery

in this work, a new spectrophotometric method for the determination of trace amount of cobalt (іі) ionwas investigated and the stability constant of the related complex was evaluated 2.174 × 104. in the cobalt(іі)-piroxicam complex, the maximum absorbance wavelength is 570 nm and the linearity of calibrationcurve was investigated (5-10 ppm). the relative standard deviation for seven replicate experiments is0.5292 percent. the accuracy is 0.15 percent and limit of detection is 1.19 ppm. the analytical sensitivityallows us to detect the concentration difference of 0.06 ppm with reliable level of confidence. the ligand tometal ratio was determined (1:1) by the continuous variation method. the above spectrophotometricmethod was optimized in terms of ph, temperature, time, ligand concentration and ionic strength. thismethod is tolerant against several external matters, which means high selectivity.