Development of electrochemical aptasensors detecting phosphate ions on TMB substrate with epoxy-based mesoporous silica nanoparticles. (June 2022)

• Record Type: Journal Article
• Authors: Altuner, Elif Esra; Ozalp, Veli Cengiz; Yilmaz, M. Deniz; Sudagidan, Mert; Aygun, Aysenur; Acar, Elif Esma; Tasbasi, Behiye Busra; Sen, Fatih
• Is Part Of: Chemosphere. Volume 297(2022)
• Publication Date: 2022-06
• Subjects: 3.3′ 5.5′tetra methyl benzidine -- Aptamer -- Aptasensor -- Mesoporus silica nanoparticles -- Phosphate ions; Pollution -- Periodicals; Pollution -- Physiological effect -- Periodicals; Environmental sciences -- Periodicals; Atmospheric chemistry -- Periodicals; 551.511
• DOI: 10.1016/j.chemosphere.2022.134077
• Languages: English
• ISSNs: 0045-6535

Abstract

Abstract: This study, it is aimed to develop an electrochemical aptasensor that can detect phosphate ions using 3.3′5.5′ tetramethylbenzidine (TMB). It is based on the principle of converting the binding affinity of the target molecule phosphate ion (PO4 3− ) into an electrochemical signal with specific aptamer sequences for the aptasensor to be developed. The aptamer structure served as a gate for the TMB to be released and was used to trap the TMB molecule in mesoporous silica nanoparticles (MSNPs). The samples for this study were characterized by transmission electron spectroscopy (TEM), Brunner-Emmet-Teller, dynamic light scattering&electrophoretic light scattering, and induction coupled plasma atomic emission spectroscopy. According to TEM analysis, MSNPs have a morphologically hexagonal structure and an average size of 208 nm. In this study, palladium-carbon nanoparticles (Pd/C NPs) with catalytic reaction were used as an alternative to the biologically used horseradish peroxidase (HRP) enzyme for the release of TMB in the presence of phosphate ions. The limit of detection (LOD) was calculated as 0.983 μM, the limit of determination (LOQ) was calculated as 3.276 μM, and the dynamic linear phosphate range was found to be 50–1000 μM. The most important advantage of this bio-based aptasensor assembly is that it does not contain molecules such as a protein that cannot be stored for a long time at room temperature, so its shelf life is very long compared to similar systems developed with antibodies. The proposed sensor shows good recovery in phosphate ion detection and is considered to have great potential among electrochemical sensors. Graphical abstract: Image 1 Highlights: An electrochemical aptasensor that can detect phosphate ions has been developed. For the aptamer study, firstly MSNPs were synthesized. TMB(ox) was trapped in the synthesized MSNPs. TMB release was observed in the presence of phosphate ions.