Tetrahedral DNA Nanostructure-Engineered Paper-Based Sensor with an Enhanced Antifouling Ability for Photoelectrochemical Sensing

Abstract

Herein, a newly designed two-in-one tetrahedral DNA (TDN) nanostructure with an antifouling surface and backbone-rigidified interfacial tracks was developed for highly sensitive and selective detection of miRNA-182-5p. The well-regulated TDN tracks were assembled onto the surface of the TiO 2 /MIL-125-NH 2 -functionalized paper electrode, which efficiently avoided the obstacle of DNA strand tangling and decreased the probability of suspension during the walking process, thus greatly promoting the moving efficiency of DNA walkers. More interestingly, the TDN-modified sensing interfaces demonstrated incomparable antifouling ability against protein samples and interfering miRNAs due to the strong hydrophilic capacity and special molecular conformations, which addressed the dilemma of low sensitivity from traditional antifouling coating strategies. As a proof of concept, the designed bifunctional tetrahedron-modified paper-based photoelectrochemical sensor was successfully used to quantify miRNA-182-5p with a low detection limit of 0.09 fM and high specificity and was validated for monitoring of miRNA-182-5p in real samples. This TDN-engineered biointerface could be used as a universal platform for tracking various targets by substituting the biorecognition events, providing great promise for bioanalysis and clinical diagnosis.

Highly Specific Aptamer–Antibody Birecognized Sandwich Module for Ultrasensitive Detection of a Low Molecular Weight Compound

“…Thus, the strand displacement reaction would drive the swing arm to move autonomously along the TDN, until all S 0 -Fc were eliminated for reaching the “signal on” state. The walking efficiency of the aptamer fixed in TDN − was notably enhanced via the kinetics study in Figure S8.…”

Orderly Aggregated Catalytic Hairpin Assembly for Synchronous Ultrasensitive Detecting and High-Efficiency Co-Localization Imaging of Dual-miRNAs in Living Cells

“…MicroRNAs (miRNAs) are a kind of single-stranded noncoding RNA composed of 18–24 nucleotides, which participate in the regulation of many physiological processes by controlling mRNA translation. – A great deal of research evidence identify that the imbalance of specific miRNA expression is closely related to the occurrence of cancer or other pathological conditions, so some specific miRNAs have been identified as biomarkers for cancer diagnosis, therapy, and prognosis. – Pancreatic ductal adenocarcinoma (PDAC) is considered to be one of the mortal neoplasms with the worst prognosis, which is difficult to diagnose at an early stage. – Previous studies have demonstrated that miRNA-196a is significantly upregulated but miRNA-217 is markedly downregulated in PDAC, while miRNA-217 was highly expressed and miRNA-196a was low expressed in normal pancreas . Therefore, exploring simultaneous ultrasensitive detection and precise colocalization imaging of miR-217 and miR-196a in living cells holds immense importance in the early diagnosis of pancreatic cancer and ensure detection specificity.…”

Tetrahedral DNA Nanostructure-Engineered Paper-Based Electrochemical Aptasensor for Fumonisin B1 Detection Coupled with Au@Pt Nanocrystals as an Amplification Label

“…However, a key obstacle in the design of the aptasensor is to tackle the crowding and entanglement of Apt at the electrode resulted from the uncontrollable density and orientation of Apt . Tetrahedral DNA nanostructures (TDNs) possess good mechanical rigidity, structural stability, and well-controlled orientation. , TDNs could act as scaffolds to anchor Apt and efficiently avoid the surface crowding and intertwining effects, improving the binding efficiency of Apt toward targets. Thus, the TDN-engineered sensing platform was used to controllably anchor FB1 Apt in this work, aiming to improve the sensitivity of the aptasensor.…”