Abstract

Potentiometric Sensor for Determination of Tramadol Hydrochloride in Pharmaceutical Preparations and Biological Fluids

Hazem M. Abu Shawish, Ayoub R. Al-Dalou, Nasser Abu Ghalwa and Anwar A. Abou Assi

A potentiometric tramadol-selective electrode based on the ion-association of tramadol hydrochloride (TDCl) with phosphomolybdic acid (TD-PM) is developed. The electrode exhibits a Nernstian slope of 58.3±0.7 mV/decade for tramadol ions in the concentration range 2.0 × 10 -6 - 1.0 × 10 -1 M with the limit of detection of 1.3 × 10 -6 M. The electrode has a fast and stable response time 5-8 s, good reproducibility and it can be used in pH range of 1.8-6.1. The present electrode show good discrimination of tramadol hydrochloride from several inorganic, organic ions, sugars and some common drug excipients. These characteristics of the electrode enable it to be used successfully for determination of tramadol hydrochloride in its pharmaceutical preparations and biological fl uids (urine and milk).