High-Performance Ratiometric Electrochemical Method Based on the Combination of Signal Probe and Inner Reference Probe in One Hairpin-Structured DNA

Abstract

In this work, the dual signal-tagged hairpin structured DNA (dhDNA)-based ratiometric probe was developed by the combination of ferrocene-labeled signal probe (Fc-sP) and methylene blue-modified inner reference probe (MB-rP) in one hairpin-structured DNA. On the basis of this, a high-performance ratiometric electrochemical method was proposed for biomarker detection. In contrast to the conventional ratiometric electrochemical probe, this dhDNA ratiometric probe integrated sP and rP into one structure, which ensured the completely same modification condition and the interdependence of sP and rP on one sensing interface. As a result, the dhDNA ratiometric probe possesses a stronger ability to eliminate the disturbance of environmental change, which was proven by the fact that the changes of the surface roughness and pH value had no significant effects on the reproducibility and stability of the sensor. Moreover, in the proposed strategy, the initial ratio responses of Fc-sP to MB-rP ((I/I)) are controllable and can be kept constant at 1:1, which is favorable for the increase in signal-to-noise ratio and sensitivity. When the sequence of Fc-sP is designed as the aptamer of mucin 1 (MUC1), the dhDNA ratiometric sensor with signal amplification of Au nanoparticles becomes feasible for the sensitive detection of MUC1 by one-step incubation procedure. Compared with the conventional ratiometric sensor, the proposed dhDNA sensor has higher reproducibility, accuracy, stability, sensitivity, and simplicity, which are significant for the development of the sensor in various fields for practical applications.

Mini Gold Nanorods with Tunable Plasmonic Peaks beyond 1000 nm

“…Gold nanoparticles (AuNPs) have been widely used in catalysis, 1–3 sensing, 4,5 imaging, 6–8 and therapeutics 8–10 due to their tunable sizes, tailorable optoelectronic properties, and straightforward surface modification. 11–15 Most applications of AuNPs rely on their shape- and size-dependent plasmonic properties.…”

A multifunctional ratiometric electrochemical sensor for combined determination of indole-3-acetic acid and salicylic acid

“…The ratio of the two signals is used to replace the absolute value of signal of analyte as the output signal, thus the reproducibility and robustness of the sensor can be remarkably enhanced. Nowadays, ratiometric electrochemical sensors have been developed for a varieties of biomolecules including nucleic acid, 22,23 biological small molecule, 24,25 protein, 26,27 and metal ions, 28,29 etc. But most ratiometric electrochemical sensors only can detect one analyte.…”

Ratiometric Electrochemical Sensing Strategy for the Ultrasensitive Detection of Telomerase Activity

“…The limit of detection is calculated to be 0.02 cells/μL (S/N=3). The stability of the ratiometric strategy is also improved by the use of the internal control . The proposed electrochemical ratiometric method exhibits a wide linear range and lower limit of detection than other representative analytical methods with single signal output (Table ).…”