Enhanced performance of reagent-less carbon nanodots based enzyme electrochemical biosensors

This work reports on the advantages of using carbon nanodots (CNDs) in the development of reagent-less oxidoreductase-based biosensors. Biosensor responses are based on the detection of H2O2, generated in the enzymatic reaction, at 0.4 V. A simple and fast method, consisting of direct adsorption of...

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Detalhes bibliográficos
Autores: Bravo Segura, Iria, Gutiérrez Sánchez, María Cristina, García Mendiola, Tania, Revenga Parra, Mónica, Pariente Alonso, Félix, Lorenzo Abad, Encarnación
Tipo de documento: artigo
Data de publicação:2019
País:España
Recursos:Universidad Autónoma de Madrid
Repositório:Biblos-e Archivo. Repositorio Institucional de la UAM
Idioma:inglês
OAI Identifier:oai:repositorio.uam.es:10486/715463
Acesso em linha:http://hdl.handle.net/10486/715463
https://dx.doi.org/10.3390/s19245576
Access Level:Acceso aberto
Palavra-chave:Carbon nanodots
nanomaterials
oxidoreductase-based biosensors
l-lactate biosensor
electrochemical techniques
lactate oxidase
glucose oxidase
uricase
Química
Descrição
Resumo:This work reports on the advantages of using carbon nanodots (CNDs) in the development of reagent-less oxidoreductase-based biosensors. Biosensor responses are based on the detection of H2O2, generated in the enzymatic reaction, at 0.4 V. A simple and fast method, consisting of direct adsorption of the bioconjugate, formed by mixing lactate oxidase, glucose oxidase, or uricase with CNDs, is employed to develop the nanostructured biosensors. Peripherical amide groups enriched CNDs are prepared from ethyleneglycol bis-(2-aminoethyl ether)-N,N,N0 ,N0 -tetraacetic acid and tris(hydroxymethyl)aminomethane, and used as precursors. The bioconjugate formed between lactate oxidase and CNDs was chosen as a case study to determine the analytical parameters of the resulting L-lactate biosensor. A linear concentration range of 3.0 to 500 µM, a sensitivity of 4.98 × 10−3 µA·µM−1 , and a detection limit of 0.9 µM were obtained for the L-lactate biosensing platform. The reproducibility of the biosensor was found to be 8.6%. The biosensor was applied to the L-lactate quantification in a commercial human serum sample. The standard addition method was employed. L-lactate concentration in the serum extract of 0.9 ± 0.3 mM (n = 3) was calculated. The result agrees well with the one obtained in 0.9 ± 0.2 mM, using a commercial spectrophotometric enzymatic kit