Page 66 - Practical book PC406-MNU-2025

MANSOURA NATIONAL UNIVERSIY
PHARM D- CLINICAL PHARMACY LEVEL II INSTRUNENTAL ANALYSIS (PC 406)

II- Spectrofluorimetric determination of oxybutynin

hydrochloride

 Principle:

 This spectrofluorimetric method depended on the ion-pair complex formation

between the tertiary amino group in the oxybutynin (OBT) hydrochloride and

eosin in 0.2 M acetate buffer of pH 4.

 The spectrofluorometric measurement of the quenching influence of OBT on the

native fluorescence of eosin at 548 nm after excitation at 304 nm.

 Procedures:

1) Transfer aliquots of the working standard solution into a series of 10 mL volumetric
flasks.

2) approximately 4.0 ml of distilled water were added followed by 0.5 ml of EY

(4.0 × 10−3 M); 0.5 ml of 0.2 M acetate buffer (pH 4) was added and mixed well.

38 | P a g e S e c o n d s e m e s t e r 2 0 2 4 - 2 0 2 5