Theoretical and experimental study for the biomimetic recognition of levothyroxine hormone on magnetic molecularly imprinted polymer

Author(s)

Lima Moura, Silio ^[1] ; Martinez Fajardo, Laura ^[1] ; Cunha, Leonardo dos Anjos ^[2] ; Taboada Sotomayor, Maria Del Pilar ^[3] ; Correto Machado, Francisco Bolivar ^[2] ; Araujo Ferrao, Luiz Fernando ^[2] ; Isabel Pividori, Maria ^[1]

Affiliation

^[1] Univ Autonoma Barcelona, Dept Quim, Grp Sensors & Biosensors, Bellaterra 08193 - Spain

^[2] Inst Tecnol Aeronaut, Dept Quim, BR-12228900 Sao Jose Dos Campos, SP - Brazil

^[3] Univ Estadual Sao Paulo UNESP, Dept Quim Analit, Inst Quim, BR-14801970 Araraquara, SP - Brazil

• Document type: Journal article
• Source: BIOSENSORS & BIOELECTRONICS; v. 107, p. 203-210, JUN 1 2018.
• Web of Science Citations: 10

Abstract

This study addresses the rational design of a magnetic molecularly imprinted polymer (magnetic-MIP) for the selective recognition of the hormone levothyroxine. The theoretical study was carried out by the density functional theory (DFT) computations considering dispersion interaction energies, and using the D2 Grimme's correction. The B97-D/def2-SV(P)/PCM method is used not only for studying the structure of the template the and monomer-monomer interactions, but also to assess the stoichiometry, noncovalent binding energies, solvation effects and thermodynamics properties such as binding energy. Among the 13 monomers studied in silico, itaconic acid is the most suitable according to the thermodynamic values. In order to assess the efficiency of the computational study, three different magnetic-MIPs based on itaconic acid, acrylic acid and acrylamide were synthesized and experimentally compared. The theoretical results are in agreement with experimental binding studies based on laser confocal microscopy, magneto-actuated immunoassay and electrochemical sensing. Furthermore, and for the first time, the direct electrochemical sensing of L-thyroxine preconcentrated on magnetic-MIP was successfully performed on magneto-actuated electrodes within 30 min with a limit of detection of as low as 0.0356 ng mL(-1) which cover the clinical range of total L-thyroxine. Finally, the main analytical features were compared with the gold standard method based on commercial competitive immunoassays. This work provides a thoughtful strategy for magnetic molecularly imprinted polymer design, synthesis and application, opening new perspectives in the integration of these materials in magneto-actuated approaches for replacing specific antibodies in biosensors and microfluidic devices. (AU)

• FAPESP's process: 14/50945-4 - INCT 2014: National Institute for Alternative Technologies of Detection, Toxicological Evaluation and Removal of Micropollutants and Radioactivies
• Grantee: Maria Valnice Boldrin
• Support Opportunities: Research Projects - Thematic Grants
• FAPESP's process: 14/25264-3 - Development and application of new nanoestructurated chemical sensors based on biomimetic polymers
• Grantee: Maria Del Pilar Taboada Sotomayor
• Support Opportunities: Regular Research Grants
• FAPESP's process: 17/07707-3 - Excited states and biradicalar nature of poliacenes and periacenes
• Grantee: Francisco Bolivar Correto Machado
• Support Opportunities: Regular Research Grants