Uni and Simplex Optimization for the Spectrophotometric Determination of Erythromycin ethylsuccinate Drug via Charge-Transfer Complex Formation

Charge transfer complex formation method has been applied for the spectrophotometric determination of erythromycin ethylsuccinate, in bulk sample and dosage form. The method was accurate, simple, rapid, inexpensive and sensitive depending on the formed charge- transfer complex between cited drug and, 2,3-Dichloro-5,6-dicyano-p- benzoquinone (DDQ) as a chromogenic reagent. The formed complex shows absorbance maxima at 587 nm against reagent blank. The calibration graph is linear in the ranges of (10 - 110) µg.mL-1 with detection limit of 0.351µg.mL-1. The results show the absence of interferences from the excipients on the determination of the drug. Therefore the proposed method has been successfully applied for the determination of erythromycin ethylsuccinate in pharmaceutical preparations. Keywords: Simplex, Spectrophotometric, Erythromycin ethylsuccinate , Charge- transfer