Fig. 3

Optimization of various parameters a pH of the phosphate buffer, b volume of DDQ reagent, c standing time, and d temperature that affects the absorbance of the charge transfer complex formed between IPR and FEN (30.0 µg/mL) and DDQ reagent
Optimization of various parameters a pH of the phosphate buffer, b volume of DDQ reagent, c standing time, and d temperature that affects the absorbance of the charge transfer complex formed between IPR and FEN (30.0 µg/mL) and DDQ reagent