Incorporating Hydrophobic Moieties into Self-Assembled Monolayers to Enable Electrochemical Aptamer-Based Sensors Deployed Directly in a Complex Matrix

Abstract

Continuous real-time measurement of specific targets in complex biological samples is of great significance for early diagnosis and treatment of diseases and thus enables achievement of personalized medicine. Electrochemical aptamer-based (E-AB) sensors are good candidates to fill this role due to their high specificity, sensitivity, rapid detection, and simple preparation. However, this sensor class suffers from severe baseline drift in the complex matrix probably due to the nonspecific adsorption of components. Here, we introduce a series of self-assembled monolayers with a variety of hydrophobic functional groups into an E-AB sensor platform, achieving enhancement of the antifouling performance and thus the detection performance (e.g., stability, sensitivity, and specificity). We reveal that the antifouling performance enhanced by such hydrophobic SAMs is probably due to its instant adsorption of components onto the surface, rather than the repelling of these components by hydrophilic SAMs in previous reports.

Highly Uniform DNA Monolayers Generated by Freezing‐Directed Assembly on Gold Surfaces Enable Robust Electrochemical Sensing in Whole Blood

“…Moreover, fouling in biological samples is unavoidable, resulting in a short lifetime and poor sensing performance [10] . It is then necessary to engineer the monolayers with antifouling molecules [10a,11] or porous architectures [12] . However, these strategies require either less cost‐effective reagents or multiple steps of surface modification.…”

Vacancy defects on structural and optoelectronic properties of double perovskite Cs2AgInCl6: A density functional theory investigation

“…However, their toxicity, as well as thermodynamic instability and the possibility of decomposition upon exposure to light and moisture, limit their photovoltaic applications [17,18]. Researchers have addressed the issues caused by toxicity and instability by developing various strategies, such as multiple-cation substitution [19], hydrophobic moiety incorporation [20], surface passivation of a perovskite absorbers [21], carbon encapsulation [22] and a low-dimensionality scheme or treatment [23]. Among these strategies, the most promising and feasible approach is to replace the Pb element with non-toxic elements [24].…”