Synthesis and characterization of a material derived from 4-mercaptobenzoic acid: A novel platform for oligonucleotide immobilization.
This paper reports the electrochemical modification of pencil carbon graphite electrodes with a polymeric material derived from 4-mercaptobenzoic acid. Acidic solutions (pH 0 and 5.02) yielded an insulating polymeric film with anionic permselective properties. Scanning Electron Microscopy (SEM) analysis showed a complete coverage of the carbon graphite electrodes with a laminar-like polymeric structure. Different characterization studies indicate that the carboxyl group remained unchanged since the absorbance peak and oxidation potential did not change with the increase in pH at the pKaaccounting for the carboxyl/carboxylate redox transition. The functionalized matrix was activated using carbodiimide, succinimide and an amine-modified oligonucleotide. The immobilization and hybridization processes were successfully verified using the redox electroactive indicator methylene blue, where better electrochemical signals were obtained when compared with the traditional self-assembled monolayer system. The selectivity of the system was verified using a noncomplementary target where no significant difference in electric current was observed when compared to the system containing only the probe. The method showed a good linear correlation coefficient (r2=0.9915), low limit of detection (1.17nmolL-1), and an acceptable precision (RSD=2.75%). The proposed method is suitable for further studies using different sequences of oligonucleotides.
Grupo de Eletroquímica Aplicada a Polímeros e Sensores - Laboratório de Eletroanalítica Aplicada à Biotecnologia e Engenharia de Alimentos - Instituto de Química - Universidade Federal de Uberlândia - Campus Patos de Minas -Av. Getúlio Vargas, 230, 38700-128 Patos de Minas, Minas Gerais, Brazil. Electronic address: rafaelfonseca@biotec.ufu.br.
Rafael da Fonseca
RDF
Alves
Grupo de Eletroquímica Aplicada a Polímeros e Sensores - Laboratório de Eletroanalítica Aplicada à Biotecnologia e Engenharia de Alimentos - Instituto de Química - Universidade Federal de Uberlândia - Campus Patos de Minas -Av. Getúlio Vargas, 230, 38700-128 Patos de Minas, Minas Gerais, Brazil. Electronic address: amandags@ealim.ufu.br.
Amanda Gonçalves
AG
da Silva
Laboratório de Eletroquímica e Nanotecnologia Aplicada - Instituto de Ciência e Tecnologia, Universidade Federal dos Vales do Jequitinhonha e Mucuri, Rodovia MGT 367, Km 583, 5000, Alto da Jacuba, Diamantina, MG 39.100-000, Brazil. Electronic address: lucas.franco@ict.ufvjm.edu.br.
Lucas Franco
LF
Ferreira
Grupo de Eletroquímica Aplicada a Polímeros e Sensores - Laboratório de Eletroanalítica Aplicada à Biotecnologia e Engenharia de Alimentos - Instituto de Química - Universidade Federal de Uberlândia - Campus Patos de Minas -Av. Getúlio Vargas, 230, 38700-128 Patos de Minas, Minas Gerais, Brazil. Electronic address: diegoleoni@ufu.br.
Diego Leoni
DL
Franco
D001565:Benzoates / Q000737:chemistry / Q000378:metabolism*; D015374:Biosensing Techniques; D004563:Electrochemistry; D004566:Electrodes; D006108:Graphite / Q000737:chemistry*; D008751:Methylene Blue / Q000378:metabolism; D009693:Nucleic Acid Hybridization / Q000379:methods*; D009841:Oligonucleotides / Q000737:chemistry / Q000378:metabolism*; D010084:Oxidation-Reduction; D011108:Polymers / Q000737:chemistry / Q000378:metabolism*; D013438:Sulfhydryl Compounds / Q000737:chemistry / Q000378:metabolism*
D001565:Benzoates; D009841:Oligonucleotides; D011108:Polymers; D013438:Sulfhydryl Compounds; C013594:4-mercaptobenzoate; D006108:Graphite; D008751:Methylene Blue
Characterization; Electrochemical technique; Oligonucleotide; Polymeric materials