تعيين محتوى حمض الحماض في السبانخ و البقدونس باستخدام تقنية الاشتقاق الكيميائي المطورة حديثا

الملخص EN

A new, improved spectrophotometric method from us, which is characterized by simplicity, sensitivity, accuracy, and specificity in oxalic acid assay, was applied to samples of spinach and parsley.

The developed method is a chemical derivatization method involving the action of a free carboxylic acid in oxalic acid, sodium nitrite releases nitrous acid which diazotizes sulfanilamide, and a diazonium salt is developed with α-naphthylamine, exhibiting maximum absorption (λ max) at 482 nm.

The effects of reaction time, reagent concentration and volume on the absorption of the complexes formed have been examined.

Beer,s law is obeyed over concentration ranges of (2-48) µg /ml (R2= 0.9972).

The precision as RSD ˃ 2%, and accuracy was determined the value of the recovery 99.66%.

The total acid content of spinach and parsley was measured volumetrically by potassium permanganate in order to compare and confirm the quantification of oxalic acid, The concentration was on spinach and parsley, respectively: (478.7 mg / 100 g) - (1360.6 mg /100 g).