Solid-contact potentiometric sensors for reliable automatic quantification of 2,4-dichlorophenol (2,4-DCP) as a food taint

Abstract

Sensitive, selective, and simple solidcontact potentiometric sensors were fabricated and characterized for 2,4dichlorophenol (2,4DCP) quantification. Membrane sensors based on the use of tridodecylmethylammonium chloride (TDMAC) and Aliquat 336 as anion exchangers were distributed in plasticized polyvinyl chloride (PVC) matrix. They revealed superNernstian responses with slopes of −70.3 and −78.2 over linear ranges 5.8 × 10 −7 -1.0 × 10 −3 M and 3.3 × 10 −6 -1.0 × 10 −3 M and with detection limits of 0.07 and 0.11 µg ml −1 , for TDMAC and Aliquat 336, respectively. The sensors were compared with conventional sensors. The effect of plasticizer on the potentiometric response and diverse foreign common ions effect were examined. Sensors of both types showed a long life span, good selectivity for 2,4DCP over a wide assortment of other common ions, long term stability, high reproducibility, and rapid response. Validation tests illustrated good performance characteristics of the recommended sensors by evaluating the lower detection limit, range, accuracy, precision, repeatability, and betweendayvariability. The sensors were effectively applied for the persistent monitoring of 2,4DCP using a flow injection system. The sensors were applied to the 2,4DCP potentiometric determination in spiked urine and fish samples. Recoveries ranged from 90% to 110%.

Tunable construction of electrochemical sensors for chlorophenol detection

“…2a, such a sensor generally consists of two basic functional units, and the signal processing normally undergoes three steps. 27–32 Firstly, the receptor unit captures the signal after its contact with target CPs. Then the transducer unit converts the signal into a useful electrochemical signal, which is finally collected by signal acquisition and processing assembly through the signal read-out techniques.…”

“…The signal read-out techniques for electrochemical detection can collect the electrical signals (current, potential, impedance, or charge) about every sampling interval of the reaction of target molecules in the analytical solution. 31–33 They are usually grouped into voltammetry, amperometry, potentiometry, conductometry, and impedimetry. 28–32 Among them, voltammetry and amperometry are more widely employed in electrochemical CP detection, and are described in detail in this section.…”

“…31–33 They are usually grouped into voltammetry, amperometry, potentiometry, conductometry, and impedimetry. 28–32 Among them, voltammetry and amperometry are more widely employed in electrochemical CP detection, and are described in detail in this section. In contrast, no previous literature is based on conductometry or impedimetry, and only one work reported potentiometric sensors for 2,4-DCP detection.…”

Single-Piece All-Solid-State Potential Ion-Selective Electrodes Integrated with Molecularly Imprinted Polymers (MIPs) for Neutral 2,4-Dichlorophenol Assessment

“…Recently, integration of MIPs with ISEs revealed a success in organics detection [24,25,26]. Only very few potentiometric sensors for 2,4-DCP determination were reported recently [24,27]. Doping of quaternary ammonium salt in polymeric membranes revealed a super-Nernstian response towards electrically neutral phenolic compounds at neutral pH values.…”

Non-Equilibrium Potential Responses towards Neutral Orcinol Using All-Solid-State Potentiometric Sensors Integrated with Molecularly Imprinted Polymers

“…In recent years, potentiometric sensors, or so-called “polymeric membrane ion-selective electrodes (ISEs)”, have become an attractive tool for determination of ionic species in different fields, such as clinical diagnostics and trace-level environmental assessment [1,2,3,4,5]. This can be attributed to their intrinsic advantages, such as high selectivity, ease of use, and good reliability.…”