Vitamin E (tocopherols and toeotrienols) antioxidaAU are detennined by reducing Cu(ll) to Cu(l) or Fe(IIl) to Fe(ll) in presence of vitaminE and"subsequentcomplexation of Cu(l) with bathocuproine and lor Fe(1l) with 2,4,6-tris-(2' -p~y1) -s-triazine (TPTZ). Both the reactions are monitored separately, Cu(l)-bathClCUplOiull.at479 nm where as, Fe(llr (TPTZ) at 595 nm spectrophotometrically. Linear calibration ,curves are achieved for both complexes between I to 51!8 mI"l for vitamin E:The methods were applied for the determination of vitamin E in pharmaceutical preparations and edible oils. Vitamin E, from edible oils, ~ solvent exllaCted into n-hexane prior to saponification. .Furthermore, a single lined flow injection manifold was also'lcxamined. A large excess of Cu(ll) or Fe(llI) with different concentrations of vitamin E in buffer pH 4 was run on the line and constant amounts of reagent bathocuproine or TPTZ in each case was injected through the injector. The peak height shows a linear relationship for vitamin E between 0.5 to 2.5 I!g mI"l for both complexes.
S A MEMON ,M Y KHUHAWAR ,I DEVI ,
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