Cefalocin

cefaloridine

cefuroxime and cefamandole form stable coordination compounds with pd2+. The ratios of cefuroxime vs. pd2+ in the coordination compounds

for example

were found to be 1:2 and 1:1.25 by the methods of equilibrium-shift and slope-ratio. The colours of these coordination compounds were mainly brownish yellow. These cephalosporins can be determined spectrophotometrically at 400 nm

the molar absorptivities were in the range of 2300 to 5600 1·mol-1·cm-1. The sensitivities can be greatly improved by determing the residual free pd2+ in reaction between cephalosporins and pd2+ with o-hydroxyquinolphthalein-CTAB

the effective molar "desorptivities" were more than 1×1051·mol-1·cm-1