A surface acoustic wave sensor functionalized with a polypyrrole molecularly imprinted polymer for selective dopamine detection

Abstract

A surface acoustic wave sensor operating at 104 MHz and functionalized with a polypyrrole molecularly imprinted polymer has been designed for selective detection of dopamine (DA). Optimization of pyrrole/DA ratio, polymerization and immersion times permitted to obtain a highly selective sensor, which has a sensitivity of 0.55°/mM (≈ 550 Hz/mM) and a detection limit of ≈ 10 nM. Morphology and related roughness parameters of molecularly imprinted polymer surfaces, before and after extraction of DA, as well as that of the non imprinted polymer were characterized by atomic force microscopy. The developed chemosensor selectively recognized dopamine over the structurally similar compound 4-hydroxyphenethylamine (referred as tyramine), or ascorbic acid,which co-exists with DA in body fluids at a much higher concentration. Selectivity tests were also carried out with dihydroxybenzene, for which an unexpected phase variation of order of 75% of the DA one was observed. Quantum chemical calculations, based on the density functional theory, were carried out to determine the nature of interactions between each analyte and the PPy matrix and the DA imprinted PPy polypyrrole sensing layer in order to account for the important phase variation observed during dihydroxybenzene injection.

Raman Computational and Experimental Studies of Dopamine Detection

“…The level of receptor activation strongly depends on the dose administrated. The need for its accurate detection at physiological levels is largely the reason for the development of various techniques, ranging from electrochemistry [ 14 ], chromatography [ 15 ], and gravimetry [ 16 , 17 ], to optical spectroscopy [ 5 , 6 , 7 , 8 ]. From a chemical perspective, its ionizable functional groups—an ethyl ammonium, which acts as a proton acceptor, and two phenolic hydroxyls, which act as donors—can participate in DA molecular bonding.…”

“…From a chemical perspective, its ionizable functional groups—an ethyl ammonium, which acts as a proton acceptor, and two phenolic hydroxyls, which act as donors—can participate in DA molecular bonding. At physiological levels, the dominant presence of ionized DA has been reported from both experimental [ 14 , 15 , 18 ] and theoretical [ 16 , 17 , 19 ] results.…”

Dopamine detection by doped single-walled carbon nanotube biosensors: A theoretical study

“…As such, as well as to the relevance of detecting it accurately, also been used as a potent drug for activating receptors in the brain, heart muscle, kidney, and gut [13]. Additionally, it has an important role in detecting emergence of Parkinson's disease, drug abuse, and HIV infection of some cells [14][15][16]. Necessity of exact and correct detection at physiological levels of dopamine, is the principal factor for the progress of several techniques including electrochemistry [17], chromatography [18], gravimetric [19], and optical spectroscopy [20].…”

Design of Novel Electrochemical Sensors for the Selective Detection of Glyphosate

“…An interesting alternative approach consists in the design of molecularly imprinted polymer (MIP) based electrochemical sensors [2,3] for the selective detection of glyphosate. The rationale for making MIPs, is that they are low-cost, sensitive and powerful analytical tools capable of determining low concentrations of this herbicide, inferior to the limits required by the European standards (EU limit in drinking water is 0.1 μgL −1 (5.9 × 10 −10 M) [4].To achieve high sensitivities and low limits of detection, a promising route consists in increasing the specific surface area of the sensors by incorporating ZnO nanorods, which have ultra-high surface/volume ratio, and coating them with the PPy-MIP [5,6].…”