Suppression of Impedimetric Baseline Drift for Stable Biosensing

Abstract

Biosensors based on electrochemical impedance spectroscopy detect the binding of an analyte to a receptor-functionalized electrode by measuring the subsequent change in the extracted charge-transfer resistance (RCT). In this work, the stability of a long chain alkanethiol, 16-mercaptohexadecanoic acid was compared to that of a polymer-based surface linker, ortho-aminobenzoic acid (o-ABA). These two classes of surface linkers were selected due to the marked differences in their structural properties. The drift in RCT observed for the native SAM-functionalized gold electrodes was observed to correlate to the drift in the subsequent receptor functionalized SAM. This indicates the importance of the gold-molecule interface for reliable biosensing. Additionally, the magnitude of the baseline drift correlated to the percentage of thiol molecules improperly bound to the gold electrode as evaluated using X-ray photoelectron spectroscopy. Alternatively, the o-ABA-functionalized gold electrodes demonstrated negligible drift in the RCT drift. Furthermore, these polymer-functionalized gold electrodes do not require a stabilization period in the buffer solution prior to receptor functionalization. This work emphasizes the importance of understanding and leveraging the structural properties of various classes of surface linkers to ensure the stability of impedimetric measurements.

Paper-Based All-in-One Origami Nanobiosensor for Point-of-Care Detection of Cardiac Protein Markers in Whole Blood

“…The baseline drift issue is critical for EIS sensors and a conditioning step has been reported to help stabilize the R ct baseline prior to receptor functionalization and analyte attachment. 65 However, the conditioning process could be tedious, and its parameters may be different from one electrode to the other. Thus, the conditioning method may be hard to transfer for POC applications.…”

“…Note that our calibration curves for artificial plasma (Figure d–f) and whole blood samples (Figure ) bear relatively large error bars. The baseline drift issue is critical for EIS sensors and a conditioning step has been reported to help stabilize the R ct baseline prior to receptor functionalization and analyte attachment . However, the conditioning process could be tedious, and its parameters may be different from one electrode to the other.…”

Electrochemical Detection of Metronidazole by the Fabricated Composites of Orthorhombic Iron Tungsten Oxide Decorated with Carbon Nanofiber Composites Electrode

“…[6][7][8][9] Moreover, electrochemical sensors are highly preferable for analytical techniques such as biosensors, aptamers, chemosensors, etc. [10][11][12] Besides, electrochemical detection methods are currently highly focused on determining MTD due to their portability, ease of handling use, sensitivity, exact detection, strong repeatability, and reproducibility. 13 An aromatic nitro group of MTD has reduced on the different electrode surfaces such as screen-printed carbon electrodes, glassy carbon electrodes, gold electrodes, and carbon paste electrodes.…”

SERS Detection of Rhodamine-6G on Ion Beam Nanostructured Ultra-Thin Gold (Au) Films: A Correlation between Fractal Growth, Water Contact-Angle and Raman Intensity

“…8 Nanostructures' shapeand size-dependent characteristics are exploited in a variety of applications, including optical, electrical, medicinal, and biological devices. [9][10][11][12] To create nanostructures with the needed features and to comprehend the underlying mechanisms, it is crucial to develop dependable production techniques. 13 Nanostructures are created using a variety of techniques.…”

“…Progress in nanoscience and nanotechnology is helping to create highly sensitive electrochemical and biosensors. 6,11,21,22 An energetic ion loses energy through a series of collisions with the atoms in a thin film that has been applied to a substrate. 23 Secondary collisions between the recoiling atoms and the thin film can produce more recoiling atoms, which could then continue in this manner.…”