## 3 Molecular Imprinting by Electropolymerization
[87] proposed a sensor for melamine detection that involved the electropolymerization of aniline in order to obtain the MIP film. In this case, a three-electrode system with GCE (working electrode), Pt electrode (counter electrode) and Ag/AgCl electrode (reference electrode) was employed and the electrodeposition of the MIP film was carried out in potentiodynamic conditions, by applying a potential between \(-\)0.2 and 1 V for 10 scan cycles. This group [87] evaluated the properties of prepared sensors by CV and SWV, in which case they obtained a higher detection limit (4.47 \(\times\) 10\({}^{-10}\) M) compared to the previous work [86]. [PERSON] and his team [88] developed an MIP sensor for electrochemical detection of asulam herbicide or methyl \(N\)-(4-aminophenylsulfonyl)carbamate. In the first step, the GCE was modified with g-C\({}_{3}\)N\({}_{4}\) (synthesized powder) and, subsequently, used for the electrodeposition of the MIP. The MIP solution consisted of monomer (dopamine), the template molecule (asulam) and electrolyte (KCl) dissolved intra-buffered saline (TBS) (pH = 7), which was electropolymerized in the \(-\)0.5 to 0.5 V potential range, for 10 cycles. The electrochemical behavior was analyzed using different methods, including CV, DPV and EIS, which led to the conclusion that the sensors possess high selectivity and affinity towards asulam, with an LOD close to 0.17 pM [88]. [PERSON] and colleagues [89] studied and developed a sensor based on MIP for electrochemical detection of luteolin, using a three-electrode system (ITO as the working electrode, SCE as a reference electrode and Pt electrode as counter electrode). The MIP film synthesis was achieved by electropolymerization of \(\beta\)-cyclodextrintrin (monomer) in the presence of luteolin, applying a potential between \(-\)0.8 and 1.1 V for 20 cycles. Rebinding and selectivity experiments were performed by contacting the sensor with luteolin, respectively with quercetin and apigenin solutions and studied by DPV. In this case, the sensor detection limit for luteolin was near 2.4 \(\times\) 10\({}^{-8}\) M [89]. [PERSON] and co-workers [90] proposed a two-step fabrication process of an electrochemical MIP-based sensor for detection of 4-nonylphenol (4-NP) in milk samples. In the first step, a multilayer electrode was obtained using reduced graphene and HAuCl\({}_{4}\). In the second step, the MIP film was prepared by electropolymerization of p-aminothiophenol (monomer), in presence of 4-NP as template molecule, upon applying a potential between \(-\)1 and 1 V. CV and DPV were employed for determining the sensor characteristics, in which case indicated a good selectivity and a LOD of 0.01 ng/mL [90]. The study by [PERSON] and her group [91] presented an MIP sensor for electrochemical detection of anthracene using GCE. The procedure was performed in a potential range between 0 and 1.4 V or 0 and 1.2 V, at a scanning rate of 10 mV/s, for 5 scan cycles, using pyrrole as a monomer and anthracene as a template molecule. The rebinding of anthracene was detected by SWV when a detection limit of 12 nM was calculated [91]. Recently, [PERSON] et al. [92] proposed a sensor based on MIP that allowed for detecting and identifying components from cocaine samples. Identification of the components provides important information regarding the origin of the cocaine. Herein, the MIP film was synthesized by electropolymerization of 3-amino-4-hydroxybenzoic in the presence of anesthetic benzocaine as the template molecule, on the carbon electrode of a SPCE. The electropolymerization process was performed in a potential range between 0 and 1.5 V for 10 scan cycles at a scan rate of 100 mV/s. SWV and EIS were used to study the electrochemical behavior of the films after contact with artificial urine (containing benzocaine) or caffeine, aminopyrine and procaine, in which case a limit of detection of 2.9 nM was achieved [92]. [PERSON] and co-workers [93] have also described a sensor developed using MIP films that can be used for entacapone detection.