were procured from Sigma (St. Louis,
MO, USA). Sodium phosphate (monobasic and dibasic), anhydrous
sodium sulfate, ammonium molybdate, ferric chloride
anhydrous, potassium ferric-cyanide, anhydrous sodium acetate,
tri-chloroacetic acid (TCA) and potassium persulfate were procured
from SRL Chemicals (Mumbai, India).