title: MIP-graphene-modified glassy carbon electrode for the determination of trimethoprim.
abstract: A novel sensitive electrochemical sensor was developed by electropolymerization of pyrrole (PY) and molecularly imprinted polymer (MIP) which was synthesized onto a glassy carbon electrode (GCE) in aqueous solution using cyclic voltammetry in the presence of Trimethoprim (TMP) as template molecules. Furthermore, a previous electrode modification was performed by deposition of a suspension of graphene on the electrode's surface. The performance of the imprinted and non-imprinted (NIP) films was evaluated by impedance spectroscopy (EIS) and cyclic voltammetry (CV) of a ferric solution. The molecularly imprinted film exhibited a high selectivity and sensitivity toward TMP. The sensor presented a linear range, between peak current intensity and logarithm of TMP concentration between 1.0 × 10(-6) and 1.0 × 10(-4)M. The results were accurate (with recoveries higher than 94%), precise (with standard deviations less than 5%) and the detection limit was 1.3 × 10(-7)M. The new sensor is selective, simple to construct and easy to operate. The MIP sensor was successfully applied to quantify TMP in urine samples.
authors.affiliation: REQUIMTE, Instituto Superior de Engenharia do Porto, Instituto Politécnico do Porto, Rua Dr António Bernardino de Almeida 431, 4200-072 Porto, Portugal.
authors.forename: Hélder
authors.initials: H
authors.lastname: da Silva
authors.forename: João G
authors.initials: JG
authors.lastname: Pacheco
authors.forename: Júlia M C S
authors.initials: JM
authors.lastname: Magalhães
authors.forename: Subramanian
authors.initials: S
authors.lastname: Viswanathan
authors.forename: Cristina
authors.initials: C
authors.lastname: Delerue-Matos
mesh_terms: D002244:Carbon / Q000737:chemistry*; D058266:Dielectric Spectroscopy; D004566:Electrodes; D006108:Graphite / Q000737:chemistry*; D011108:Polymers / Q000737:chemistry; D014295:Trimethoprim / Q000737:chemistry / Q000302:isolation & purification*
chemical_list: D011108:Polymers; D002244:Carbon; D006108:Graphite; D014295:Trimethoprim
keywords: Electrochemical sensor; Graphene; Molecularly Imprinting Polymer (MIP); Pyrrole; Trimethoprim