Further insight into the possible influence of electrode blocking agents on the stem-loop based electrochemical DNA sensor parameters

Electrochemical detection of SARS-CoV-2 based on copper nanoflower-triggeredin situgrowth of electroactive polymers

“…On the gold electrode, the 5′-end azide and 3′-end sulfhydryl double-labeled Sp were modified, followed by the addition of MCH to occupy the nonspecific adsorption site for blocking. 30 In the presence of AA, Cu( ii ) of the copper nanoflowers can be reduced to Cu( i ) and released, catalyzing PBIB to be anchored on the electrode surface through the CuAAC reaction. Then, eATRP reaction was carried out to polymerize the signal molecules’ FMMA grafting onto the modified electrode surface for the quantitative detection of SARS-CoV-2.…”

Strategy, Design, and Fabrication of Electrochemical Biosensors: A Tutorial

“…The most commonly used blocking agent is mercaptohexanol (MCH) that facilitates a 90° orientation of DNA strands and thereby favors a configuration for subsequent hybridization. There are also reports of other blocking agents in the literature such as mercaptoethanol, cysteamine hydrochloride, and benzenedithiol, to name a few . In fact, blocking agents are usually underappreciated in an academic setting, but industry experts are aware that reducing unwanted adsorption is key to a low background signal and device performance.…”

“…Whereas the labeled systems involve redox mediators or enzymes in the configuration given in Figure a–e. There are also reports of DNA strands labeled with nanoparticles and ones monitoring their redox properties …”

“…There are also reports of other blocking agents in the literature such as mercaptoethanol, cysteamine hydrochloride, and benzenedithiol, to name a few. 102 In fact, blocking agents are usually underappreciated in an academic setting, but industry experts are aware that reducing unwanted adsorption is key to a low background signal and device performance.…”

Recent Progress on Highly Selective and Sensitive Electrochemical Aptamer-based Sensors

“…When covalent strategies carried out on the electrode surface, it is difficult to ensure that aptamers completely cover the whole electrode surface. In order to prevent electrochemical active substances from reacting on the unmodified electrode surface and producing false-positive electrical signals, it is usually necessary to add blocking agents to passivate the unmodified area on the electrode surface [110] .…”