Development of a Simple, Selective, Stable and Ultrasensitive Poly(safranine/nano NiO) Modified Carbon Paste Electrode for Selective Detection of Rutin in Buckwheat and Green Tea Samples

Present study demonstrates the construction of a new electrochemical sensor by electropolymerization of safranine on the surface of modified nano NiO carbon paste electrode. Cyclic and differential pulse voltammetric techniques were applied for the detection of rutin using 0.1 M phosphate buffer solution (pH 5.5) as supporting electrolyte. Specific variables including solution pH, analyte concentration and scan rates were optimized to validate the method. The peak currents were proportional with rutin concentration between 1.61x10(-8) M to 2.30x10(-7) M. The assessed limit of detection and limit of quantification values were found to be 0.54x10(-8) M and 1.61x10(-8) M respectively. The modified poly(safranine/nano NiO)CPE was successfully employed for the selective quantification of rutin in buckwheat and green tea samples in presence of other interfering substances. The recoveries were found consistent between 96.5%-102.8% with the modified poly(safranine/nano NiO)CPE. Hence, the electrochemical response of poly(safranine/nano NiO)CPE for the detection of rutin was greatly enhanced after electropolymerization, which is 3 times higher than the nano NiO modified CPE and 6 times higher than the bare CPE. Overall, the proposed poly(safranine/nano NiO)CPE has showed superior electrocatalytic activity and higher sensitivity for the selective detection of rutin in real samples.