A Novel Potentiometric Sensor for Determination of Tramadol in Biological Samples

Document Type : Original Article


1 Department of Chemistry, Payame Noor University (PNU), Tehran, Iran

2 Department of Chemistry, Faculty of Science, Yazd University, Yazd, 89195-741, I.R. Iran


A unique potentiometric ion-selective PVC membrane sensor was developed based on tramadol-(tetraphenylborate) as the sensing element, tetraphenylborate as an additive, and dibutyl phthalate (DBP) as the plasticizer solvent for the measurement of Tramadol in pharmaceutical preparations. Different parameters such as the electrode conditioning time, the effect of electrode materials, and the impact of pH solution on the electrode performance were evaluated. The electrode showed a Nernstian slope of 59.5±0.4 mV/decade for tramadol ions. The potentiometric sensor reported here has been optimized to provide excellent analytical performance with a linear in the concentration spectrum 1.0×10-7-1.0×10-1 mol L-1 and a limit of quantification of 7.0×10-8 mol L-1. The sensor has a reaction time of 5 seconds and can be utilized in the pH range of 2.0 to 7.0. With a mean relative standard deviation of less than 2%, the approach is effective and reliable. The current electrode would be used to detect tramadol hydrochloride in biological samples with excellent results.