Reduced Graphene Oxide and Gold Nanoparticles-Modified Electrochemical Aptasensor for Highly Sensitive Detection of Doxorubicin

Abstract

Doxorubicin (DOX) is the most clinically important antibiotic in cancer treatment, but its severe cardiotoxicity and other side effects limit its clinical use. Therefore, monitoring DOX concentrations during therapy is essential to improve efficacy and reduce adverse effects. Here, we fabricated a sensitive electrochemical aptasensor for DOX detection. The sensor used gold wire as the working electrode and was modified with reduced graphene oxide (rGO)/gold nanoparticles (AuNPs) to improve the sensitivity. An aptamer was used as the recognition element for the DOX. The 5′ end of the aptamer was modified with a thiol group, and thus immobilized to the AuNPs, and the 3′ end was modified with methylene blue, which acts as the electron mediator. The combination between the aptamer and DOX would produce a binding-induced conformation, which changes the electron transfer rate, yielding a current change that correlates with the concentration of DOX. The aptasensor exhibited good linearity in the DOX concentration range of 0.3 μM to 6 μM, with a detection limit of 0.1 μM. In addition, the aptasensor was used for DOX detection in real samples and results, and showed good recovery. The proposed electrochemical aptasensor will provide a sensitive, fast, simple, and reliable new platform for detecting DOX.

A Multienzyme Reaction-Mediated Electrochemical Biosensor for Sensitive Detection of Organophosphorus Pesticides

“…The electrocatalysis and adsorptive properties of graphene receive attention; at the same time, Au NPs could improve adsorption. Graphene and Au NPs have a synergistic effect [25]. Therefore, a composite material of graphene and Au NPs was prepared.…”

Emerging Roles of Microrobots for Enhancing the Sensitivity of Biosensors

“…More importantly, aptamers have high specificity for certain targets, ranging from small molecules to large proteins and even cells, which offers remarkable flexibility and convenience for designing biosensors with high sensitivity and selectivity [75][76][77][78]. Compared with antibodies or enzymes, aptamers have higher chemical stability and convenience in the structure design [79][80][81][82][83]. Recent researches revealed the development for designing new fluorescence (bio)-sensing strategies based on artificial microrobots.…”