Electrochemical Signal Substance for Multiplexed Immunosensing Interface Construction: A Mini Review

Abstract

Appropriate labeling method of signal substance is necessary for the construction of multiplexed electrochemical immunosensing interface to enhance the specificity for the diagnosis of cancer. So far, various electrochemical substances, including organic molecules, metal ions, metal nanoparticles, Prussian blue, and other methods for an electrochemical signal generation have been successfully applied in multiplexed biosensor designing. However, few works have been reported on the summary of electrochemical signal substance applied in constructing multiplexed immunosensing interface. Herein, according to the classification of labeled electrochemical signal substance, this review has summarized the recent state-of-art development for the designing of electrochemical immunosensing interface for simultaneous detection of multiple tumor markers. After that, the conclusion and prospects for future applications of electrochemical signal substances in multiplexed immunosensors are also discussed. The current review can provide a comprehensive summary of signal substance selection for workers researched in electrochemical sensors, and further, make contributions for the designing of multiplexed electrochemical immunosensing interface with well signal.

Antibody–Ferrocene Conjugates as a Platform for Electro-Chemical Detection of Low-Density Lipoprotein

“…This action is next converted into analytically useful signals by means of an electrochemical transducer [ 8 ]. The Ab–Ag immunocomplex formation can be observed by changes in the redox activity of different labels, including ferrocene, thionine, methylene blue, hemin, or antraquinone [ 9 ], and gold, silver, or quantum dots attached to antibodies [ 10 , 11 ]. There are possibilities for covalent conjugation of electrochemical labels on antibodies by combining amino groups of labels with carboxyl groups of antibodies [ 12 ].…”

Recent advancement in sensitive detection of carcinoembryonic antigen using nanomaterials based immunosensors

“…In addition, metal nanoparticles can be directly electrodeposited on immunosensing surfaces to generate the EC signal indication or act as an ideal anchor to attach biomolecules as sensing components [168]. This can be done by providing a biocompatible microenvironment to the biomolecules by using noble metal nanoparticles that substantially improve the surface-to-volume ratio of an immobilized biomolecule on the electrode surface, both of which adversely allow electrical signal enhancement [100,169]. Some of the recent examples of the NMs-based EC immunosensor fabricated for CEA detection are summarised in Table 3.…”

Electrochemical stripping analysis

“…As each biomolecular probe can accommodate a large number of quantifiable labels, very low limits of detection (in the range of femtomoles per litre) can be achieved. Additionally, multiplexed detection of several target biomolecules is possible using different metalbased nano-labels with different stripping peak potentials 212 . Reproducibility and data deposition Reproducibility aspects are related to analyte losses or contamination 213 , control of the instrumental parameters, the fabrication process itself and chemical issues, such as the formation of intermetallic compounds or the fouling of electrode surface.…”