Field Effect and Applications

Bueno, Paulo Agenor Alves

doi:10.1007/978-3-319-90487-0_3

Cited by 1 publication

(1 citation statement)

References 85 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…PMB is the polymer chain that plays as “wires”, which connect resonantly chargeable redox sites to the electrode. The binding of cortisol molecules to the receptor cavities of MICP hinders the electron transfer through adjacent PMB, which causes the PMB wires less conductive, thus leading to a decrease in resonant quantum conductance (detailed in Supporting Information Note S1). − Such phenomenon can also be explained using the equivalent circuit of the MICP (Figure B). In the equivalent circuit, the quantum conductance of the MICP is a constant, which is quantized by G 0 ( e 2 / h ) in a single-electron channel of PMB.…”

Section: Resultsmentioning

confidence: 99%

Introducing Nanoscale Electrochemistry in Small-Molecule Detection for Tackling Existing Limitations of Affinity-Based Label-Free Biosensing Applications

Lee,

Kim

2023

J. Am. Chem. Soc.

View full text Add to dashboard Cite

Electrochemical sensing techniques for small molecules have progressed in many applications, including disease diagnosis and prevention as well as monitoring of health conditions. However, affinity-based detection for low-abundance small molecules is still challenging due to the imbalance in target-to-receptor size ratio as well as the lack of a highly sensitive signal transducing method. Herein, we introduced nanoscale electrochemistry in affinity-based small molecule detection by measuring the change of quantum electrochemical properties with a nanoscale artificial receptor upon binding. We prepared a nanoscale molecularly imprinted composite polymer (MICP) for cortisol by electrochemically copolymerizing β-cyclodextrin and redoxactive methylene blue to offer a high target-to-receptor size ratio, thus realizing "bind-and-read" detection of cortisol as a representative target small molecule, along with extremely high sensitivity. Using the quantum conductance measurement, the present MICP-based sensor can detect cortisol from 1.00 × 10 −12 to 1.00 × 10 −6 M with a detection limit of 3.93 × 10 −13 M (S/N = 3), which is much lower than those obtained with other electrochemical methods. Moreover, the present MICP-based cortisol sensor exhibited reversible cortisol sensing capability through a simple electrochemical regeneration process without cumbersome steps of washing and solution change, which enables "continuous detection". In situ detection of cortisol in human saliva following circadian rhythm was carried out with the present MICP-based cortisol sensor, and the results were validated with the LC−MS/MS method. Consequently, this present cortisol sensor based on nanoscale MICP and quantum electrochemistry overcomes the limitations of affinity-based biosensors, opening up new possibilities for sensor applications in point-of-care and wearable healthcare devices.

show abstract

Section: Resultsmentioning

confidence: 99%