A Simple and Robust Exponential Amplification Reaction (EXPAR)-Based Hairpin Template (exp-Hairpin) for Highly Specific, Sensitive, and Universal MicroRNA Detection.

Specific and sensitive detection of microRNAs continues to encounter significant challenges, especially in the development of rapid and efficient isothermal amplification strategies for point-of-care settings. The exponential amplification reaction (EXPAR) has garnered significant attention owing to its simplicity and rapid amplification of signals within a short period. However, a substantial loss of amplification efficiency, difficulty in distinguishing closely related homologous sequences, and adapting the designed templates to other targets seriously hamper the practical application of the EXPAR.

T-Shaped Aptamer-Based LSPR Biosensor Using Ω-Shaped Fiber Optic for Rapid Detection of SARS-CoV-2.

SARS-CoV-2, especially the variant strains, is rapidly spreading around the world. Rapid detection methods for the virus are crucial for controlling the COVID-19 epidemic. Herein, a localized surface plasmonic resonance (LSPR) biosensor based on Ω-shaped fiber optic (Ω-FO) was developed for dual assays of SARS-CoV-2 monitoring.

Low-Triggering-Potential Electrochemiluminescence from a Luminol Analogue Functionalized Semiconducting Polymer Dots for Imaging Detection of Blood Glucose.

In recent years, semiconducting polymer dots (Pdots) as environmentally friendly and high-brightness electrochemiluminescence (ECL) nanoemitters have attracted intense attention in ECL biosensing and imaging. However, most of the available Pdots have a high ECL excitation potential in the aqueous phase (>1.0 V vs Ag/AgCl), which causes poor selectivity in actual sample detection.

Donor-Acceptor Conjugated Polymer Dots for Tunable Electrochemiluminescence Activated by Aggregation-Induced Emission-Active Moieties.

Low-potential electrochemiluminescence (ECL) luminophores with excellent ECL behavior have attracted considerable interest in biological analysis. Herein, we describe the synthesis of two aggregation-induced emission (AIE)-active conjugated polymers with a donor-acceptor (D-A) system via a Suzuki coupling polymerization reaction. The intramolecular D-A pairs enhanced their luminescence intensity in aggregate states, which was beneficial for preparation of conjugated polymer dots (Pdots) as ECL materials.

Electrochemiluminescent Imaging for Multi-immunoassay Sensitized by Dual DNA Amplification of Polymer Dot Signal.

A true-color electrochemiluminescent (ECL) imaging strategy was designed for a multi-immunoassay of proteins by coupling highly efficient polymer dots (Pdots) with dual DNA amplification. The Pdots were prepared by nanoprecipitation of poly[(9,9-dioctylfuorenyl-2,7-diyl)- alt-co-(1,4-benzo-{2,1',3}-thiadiazole)] in the presence of poly(styrene- co-maleic anhydride) and functionalized with DNA1 that hybridized with black hole quencher-labeled DNA2 to self-quench the ECL emission. The Pdots modified Au/ITO electrode showed 100-fold stronger ECL emission than the Pdots modified ITO electrode.

Highly Efficient Electrochemiluminescence of Cyanovinylene-Contained Polymer Dots in Aqueous Medium and Its Application in Imaging Analysis.

Luminescent semiconducting polymer dots (Pdots) have attracted intense attention in the field of electrochemiluminescence (ECL) due to their nontoxic features. For utilizing the nontoxic Pdots to achieve sensitive ECL bioimaging detection, this work studied the ECL behaviors of poly[2-methoxy-5-(2-ethylhexyloxy)-1,4-(1-cyanovinylene-1,4-phenylene)] (CN-PPV) Pdots in aqueous solution, which introduced an electron-withdrawing cyano group to p-phenylenevinylene for enhancing the luminescent efficiency. The CN-PPV Pdots could be both electrochemically oxidized to a positively charged state and electrochemically reduced to a negatively charged state, which led to annihilation of ECL emission.

Electrochemiluminescent resonance energy transfer of polymer dots for aptasensing.

This work designed a three-component polymer for the preparation of polymer dots (Pdots). The polymer contained 9-(diphenylmethylene)-9H-fluorene (DPF), 9,9-dioctyl-9H-fluorene (DOF) and 1,1'-binaphthyl moieties, and was synthesized via Pd-catalyzed Suzuki reaction. It exhibited obvious yellow-colored aggregation-induced emission (AIE) for fluorescence enhancement at 543nm via an intramolecular fluorescence resonance energy transfer from DOF moiety to DPF moiety.

Ru(bpy) Incorporated Luminescent Polymer Dots: Double-Enhanced Electrochemiluminescence for Detection of Single-Nucleotide Polymorphism.

Encapsulating a large amount of electrochemiluminescence (ECL) active molecules into one nanoparticle for single-target recognition can greatly improve the sensitivity of the ECL assay. This work used luminescent conjugated polymer as a carrier to synthesize Ru(bpy)-doped polymer dots (RuPdots). The RuPdots with an average size of 20 nm and encapsulation of about 1354 Ru(bpy) showed greatly enhanced ECL emission.

Pegylated folate and peptide-decorated graphene oxide nanovehicle for in vivo targeted delivery of anticancer drugs and therapeutic self-monitoring.

This work reports a graphene oxide-based nanovehicle with conjugation of pegylated folate for targeted delivery of anticancer drugs and fluorescein-labeled peptide for therapeutic self-monitoring in vitro and in vivo. The nanovehicle could absorb hydrophobic and aromatic drug molecules with high loading capacity and efficiency of more than 1.7 mg mg(-1) and 90%, respectively.

Silole-Containing Polymer Nanodot: An Aqueous Low-Potential Electrochemiluminescence Emitter for Biosensing.

A novel D-A conjugated polymer backbone containing silole and 9-octyl-9H-carbazole units was synthesized via Sonogashira reaction. This silole-containing polymer (SCP) was further used to prepare SCP dots with a nanoprecipitation method, which showed an electrochemiluminescence (ECL) emission at relatively low potential in aqueous solution. The strong anodic ECL emission could be observed at +0.

Electrochemiluminescent DNA sensing using carbon nitride nanosheets as emitter for loading of hemin labeled single-stranded DNA.

Carbon nitride nanosheets (CNNS) have been reported as a cathodic electrochemiluminescence (ECL) emitter in the presence of dissolved oxygen to produce an endogenous coreactant H2O2 on electrode surface. This work uses this emitter to construct an ECL sensing platform for sensitive DNA detection through its adsorption ability toward single-stranded DNA (ssDNA). The adsorption of hemin-labeled ssDNA on CNNS leads to in situ consumption of dissolved oxygen via hemin-mediated electrocatalytic reduction, thus decreases the formation of coreactant and quenches the ECL emission of CNNS.

Novel and high-performance asymmetric micro-supercapacitors based on graphene quantum dots and polyaniline nanofibers.

In comparison with graphene sheets, graphene quantum dots (GQDs) exhibit novel chemical/physical properties including nanometer-size, abundant edge defects, good electrical conductivity, high mobility, chemical inertia, stable photoluminescence and better surface grafting, making them promising for fabricating various novel devices. In the present work, an asymmetric micro-supercapacitor, using GQDs as negative active material and polyaniline (PANI) nanofibers as positive active material, is built for the first time by a simple and controllable two-step electro-deposition on interdigital finger gold electrodes. Electrochemical measurements reveal that the as-made GQDs//PANI asymmetric micro-supercapacitor has a more excellent rate capability (up to 1000 V s(-1)) than previously reported electrode materials, as well as faster power response capability (with a very short relaxation time constant of 115.