Cost-effective and handmade paper-based potentiometric sensing platform for piperidine determination

Abstract

For the first time, a robust, rugged, and low-cost ion sensor based on potentiometric transduction is presented here for rapid determination of piperidine. A conventional filter paper is used as a substrate to establish the sensors after coating a carbon-ink layer on the surface of the filter paper to make it conductive. Poly(3,4-ethylenedioxythiophene)/poly(styrenesulfonate) (PEDOT/PSS) was used as an ion-to-electron transducer and deposited through drop-casting on the paper-based carbon electrode. The polymeric membranes were based on the incorporation of two types of electroactive materials, namely ion association complexes such as piperidinium phosphomolybdate (Pip/PMA) (sensor I), piperidinium phosphotungstate (Pip/PT) (sensor II), piperidinium tetraphenyl borate (Pip/TPB) (sensor III), and β-cyclodextrin (β-CD) ionophore (sensor IV) in a plasticized polyvinyl chloride (PVC) matrix. The sensors revealed Nernstian slopes of 60.2 ± 0.5, 57.1 ± 0.6, 56.2 ± 0.8 and 54.2 ± 0.6 mV per decade with linear concentration ranges begin from 5.1 × 10⁻⁶, 7.4 × 10⁻⁶, 3.1 × 10⁻⁵ and 5.5 × 10⁻⁶ M for sensors I, II, III and IV, respectively. The detection limits range from 0.32 to 0.66 μg mL⁻¹ for all the proposed sensors with a response time <10 seconds. The sensors exhibited clear selectivity towards piperidinium ions over several common organic and inorganic cations. Repeatability, reproducibility and stability have been studied to evaluate the properties of the sensors. The sensors were successfully utilized for piperidine quantification in wastewater and human urine samples. The obtained results agreed well with the acceptable recovery percentage and were better than those obtained by other previously reported routine methods.