Electrochemical Biosensing in Cancer Diagnostics and Follow‐up

Abstract

In cancer, screening and early detection are critical for the success of the patient's treatment and to increase the survival rate. The development of analytical tools for non‐invasive detection, through the analysis of cancer biomarkers, is imperative for disease diagnosis, treatment and follow‐up. Tumour biomarkers refer to substances or processes that, in clinical settings, are indicative of the presence of cancer in the body. These biomarkers can be detected using biosensors, that, because of their fast, accurate and point of care applicability, are prominent alternatives to the traditional methods. Moreover, the constant innovations in the biosensing field improve the determination of normal and/or elevated levels of tumour biomarkers in patients’ biological fluids (such as serum, plasma, whole blood, urine, etc.). Although several biomarkers (DNA, RNA, proteins, cells) are known, the detection of proteins and circulating tumour cells (CTCs) are the most commonly reported due to their approval as tumour biomarkers by the specialized entities and commonly accepted for diagnosis by medical and clinical teams. Therefore, electrochemical immunosensors and cytosensors are vastly described in this review, because of their fast, simple and accurate detection, the low sample volumes required, and the excellent limits of detection obtained. The biosensing strategies reported for the six most commonly diagnosed cancers (lung, breast, colorectal, prostate, liver and stomach) are summarized and the distinct phases of the sensors’ constructions (surface modification, antibody immobilization, immunochemical interactions, detection approach) and applications are discussed.

Electrodeposition of Silver Amalgam on Thin Gold Film Electrodes for Voltammetric Detection of 4‐Nitrophenol and DNA Labeled with Osmium Tetroxide‐Bipyridine Complex

“…Recent progress in molecular diagnostics has led to discoveries of new genes, proteins, and other biomarkers, which have been shown to be involved in various diseases, carrier detection, and in primary patient or prenatal diagnosis . Electrochemical sensors and biosensors represent a prospective tool for this purpose . In electroanalysis of deoxyribonucleic acid (DNA), ribonucleic acid (RNA) and protein or glycoprotein, dropping and hanging mercury drop electrodes still hold their irreplaceable importance .…”

Electrochemical Sensing Platforms for HER2‐ECD Breast Cancer Biomarker Detection

“…Currently medical strategies for screening and early detection are based on imagiology tools, namely mammography. Therefore, their development is in continuous expansion and they have widely been applied in point-of-care detection [4,5]. Nevertheless, the evolution of clinical methods for effective detection of breast cancer along with the development of non-invasive and low-cost in situ techniques can improve survival rates and allow personalized patient follow-up [2,4].…”

“…AuNPs were used in these studies to enhance the capture antibody's immobilization and to retain its immunoactivity on the electrode [11]. Efficient bioconjugation is largely achieved by using magnetic particles comprising a magnetite core (Fe 3 O 4 MNPs) with a non-magnetic coating [5]. Arkan et al proposed an immunosensor based on multiwalled carbon nanotubes (MWCNTs) and AuNPs contained in a carbon ionic liquid electrode (CILE).…”

Electrogenerated Chemiluminescence for Chronopotentiometric Sensors

“…Electrochemical detection methods (voltammetry, amperometry, potentiometry, conductometry and electrochemical impedance spectroscopy) not only possess the advantages of simplicity, fast responses and ease of use, the instruments needed to perform the analysis can be miniaturized to low-cost microscale dimensions. [1][2][3][4] However, electrochemical signals are normally not intuitive and need numerical algorithms to allow for an interpretation of the data. Moreover, electrochemical methods become overly complex when extended to chemical detection in two dimensions and multiple channels.…”