Development of Electrochemical Aptasensor for Lung Cancer Diagnostics in Human Blood

Abstract

We describe the preparation and characterization of an aptamer-based electrochemical sensor to lung cancer tumor markers in human blood. The highly reproducible aptamer sensing layer with a high density (up to 70% coverage) on the gold electrode was made. Electrochemical methods and confocal laser scanning microscopy were used to study the stability of the aptamer layer structure and binding ability. A new blocking agent, a thiolated oligonucleotide with an unrelated sequence, was applied to fill the aptamer layer’s defects. Electrochemical aptasensor signal processing was enhanced using deep learning and computer simulation of the experimental data array. It was found that the combinations (coupled and tripled) of cyclic voltammogram features allowed for distinguishing between the samples from lung cancer patients and healthy candidates with a mean accuracy of 0.73. The capacitive component from the non-Faradic electrochemical impedance spectroscopy data indicated the tumor marker’s presence in a sample. These findings allowed for the creation of highly informative aptasensors for early lung cancer diagnostics.

Structure-Switching Electrochemical Aptasensor for Rapid, Reagentless, and Single-Step Nanomolar Detection of C-Reactive Protein

“…The apparently well-maintained sensitivity, upon changing from simplified assay buffers to partially diluted biological fluids, has been reported in numerous other studies for SS-EABs. 15,63 This observation is generally attributed to signal induction dependence on binding-induced changes to receptor physics, as opposed to sensors that depend on adsorption-based signal induction mechanisms. 64 As mentioned previously, the latter are notoriously prone to false positives and response dampening, in addition to baseline drift that is commonly attributed to the "biofouling" of the sensor surface with abundant proteins and interferants found in complex sample matrices.…”

Aptamers Enhance Oncolytic Viruses’ Antitumor Efficacy

“…Using conjugates of nucleolin aptamers (AS 1411), a susceptible and straightforward colorimetric method using UV-vis spectrometry was developed to detect MCF-7 breast cancer cells [ 91 ]. Based on the DNA aptamer LC-18, an electrochemical aptasensor for diagnosing lung cancer in human blood was developed [ 94 ]. Deep learning and computer simulation of an array of experimental data were used to process the signals of the electrochemical aptasensor for early lung cancer diagnosis.…”