A universal electrochemical biosensor based on CRISPR/Cas12a and a DNA tetrahedron for ultrasensitive nucleic acid detection.

Herein, a universal nucleic acid analysis platform was constructed for sensitive and accurate detection of miRNA-155 and ctDNA using isothermal amplification-assisted CRISPR/Cas12a and a tetrahedral DNA nanostructure (TDN) supported sensing interface. Under the optimal experimental conditions, the prepared sensor achieved specific detection of miRNA-155 and ctDNA at as low as aM levels in 2.6 h. Furthermore, the platform was also successfully applied to human serum sample recovery experiments and cancer cell lysates, demonstrating outstanding reliability and accuracy. We firmly believe that this work provides a universal, sensitive, and practical tool for early clinical diagnosis.

In Situ Construction of Inorganics-Rich Cathode-Electrolyte Interface toward Long-Life Prussian White Cathode.

Prussian white (PW) is one of the most promising candidates as a cathode for sodium-ion batteries (SIBs) because of its high theoretical capacity, excellent rate performance, and low production cost. However, PW materials suffer severe capacity decay during long-term cycling. In this work, a robust cathode electrolyte interface (CEI) is designed on the PW cathode by employing cresyl diphenyl phosphate (CDP) and adiponitrile (ADN) as electrolyte additives. CDP and ADN possess higher highest occupied molecular orbital energy levels (HOMO) than other solvents, leading to the preferential decomposition of CDP and ADN to construct an inorganics-rich CEI layer in situ on the PW cathode. Benefiting from this CEI layer, the degradation of PW is effectively inhibited during the long cycling. The Na||PW cell achieves an excellent cycling performance with a capacity retention of 85.62% after 1400 cycles. This work presented here provides a feasible strategy for improving the cycling performance of PW by electrolyte modification.

Antibody-Protein-Aptamer Electrochemical Biosensor based on Highly Efficient Proximity-Induced DNA Hybridization on Tetrahedral DNA Nanostructure for Sensitive Detection of Insulin-like Growth Factor-1.

Herein, an antibody-protein-aptamer electrochemical biosensor was designed by highly efficient proximity-induced DNA hybridization on a tetrahedral DNA nanostructure (TDN) for ultrasensitive detection of human insulin-like growth factor-1 (IGF-1). Impressively, the IGF-1 antibody immobilized on the top vertex of the TDN could effectively capture the target protein with less steric effect, and the ferrocene-labeled signal probe (SP) bound on the bottom vertex of the TDN was close to the electrode surface for generating a strong initial signal. In the presence of target protein IGF-1 and an aptamer strand, an antibody-protein-aptamer sandwich could be formed on the top vertex of TDN, which would trigger proximity-induced DNA hybridization to release the SP on the bottom vertex of TDN; therefore, the signal response would decrease dramatically, enhancing the sensitivity of the biosensor. As a result, the linear range of the proposed biosensor for target IGF-1 was 1 fM to 1 nM with the limit of detection down to 0.47 fM, which was much lower than that of the traditional TDN designs on electrochemical biosensors. Surprisingly, the use of this approach offered an innovative approach for the sensitive detection of biomarkers and illness diagnosis.

Engineering A Boron-Rich Interphase with Nonflammable Electrolyte toward Stable Li||NCM811 Cells Under Elevated Temperature.

Despite the high energy of LiNi0.8 Co0.1 Mn0.1 O2 (NCM811) cathode, it still suffers serious decay due to the continuous solvents decomposition and unstable cathode electrolyte interphase (CEI) layers, especially under high temperatures. The intense exothermic reaction between delithiated NCM811 and flammable electrolyte, on the other hand, pushes the batteries to their safety limit. Herein, these two issues are tackled via engineering the electrolytes, that is, utilizing salts with higher HOMO levels and nonflammable solvents with lower HOMO levels, to reduce the massive decomposition of solvents and improve battery safety under elevated temperatures. Consequently, a thin and boron-rich CEI is generated, which effectively inhibited the side reactions, thus improving the cycling stability and safety. Deviated from the highly concentrated electrolytes which heavily relies on the usage of massive salts, the electrolyte recipe can introduce a robust inorganic-rich CEI but use much less salt (i.e., dilute electrolyte), and thus, offer an encouraging alternative toward practical applications. As such, the NCM811 cathode exhibits a high-capacity retention of 81.2% after 950 cycles at 25 °C and 75% after 300 cycles at 55 °C. This work provides a universal electrolyte design strategy for designing stable and safe high-temperature electrolytes for the NCM811 cathode.

Tetrahedral DNA Nanostructure with Multiple Target-Recognition Domains for Ultrasensitive Electrochemical Detection of Mucin 1.

In this work, a tetrahedral DNA nanostructure (TDN) designed with multiple biomolecular recognition domains (m-TDN) was assembled to construct an ultrasensitive electrochemical biosensor for the quantitative detection of tumor-associated mucin 1 (MUC-1) protein. This new nanostructure not only effectively increased the capture efficiency of target proteins compared to the traditional TDN with a single recognition domain but also enhanced the sensitivity of the constructed electrochemical biosensors. Once the target MUC-1 was captured by the protein aptamers, the ferrocene-marked DNA strands as electrochemical signal probes at the vertices of m-TDN would be released away from the electrode surface, causing significant reduction of the electrochemical signal, thereby enhancing significantly the detection sensitivity. As a result, this well-designed biosensor achieved ultrasensitive detection of the biomolecule at a linear range from 1 fg mL-1 to 1 ng mL-1, with the limit of detection down to 0.31 fg mL-1. This strategy provides a new approach to enhance the detection sensitivity for the diagnosis of diseases.

DNA Three-Way Junction with Multiple Recognition Regions Mediated an Unconfined DNA Walker for Electrochemical Ultrasensitive Detection of miRNA-182-5p.

In this work, a DNA three-way junction (TWJ) with multiple recognition regions was intelligently engineered, which could be applied as an unconfined DNA walker with a rapid walking speed and high sensitivity for electrochemical detection of microRNA (miRNA-182-5p). Once the target miRNA was presented, the hairpins on TWJ could be successively opened to form an annular DNA walker, which could walk on the entire scope of the electrode surface without the confine for the length of DNA walker legs compared with the traditional DNA walker, greatly improving the walking efficiency. In addition, this DNA walker with multirecognition segments could obviously increase the local concentration of recognition sites, which significantly enhanced the detection speed and sensitivity. As a result, this proposed biosensor with annular DNA as a walker could dexterously achieve the ultrasensitive and fast detection of miRNA-182-5p from 0.1 fM to 1 nM with a detection limit of 31.13 aM. Meaningfully, this strategy explored an innovative path in the design of a new DNA walker nanostructure for accomplishing speedy and sensitive detection of biomarkers.