SARS-CoV-2 main protease, M, plays a crucial role in the virus replication cycle, making it an important target for antiviral research. In this study, a simplified model obtained through truncation is used to explore the reaction mechanism of aldehyde warhead compounds inhibiting M at the level of density functional theory. According to the calculation results, proton transfer (P_T)-nucleophilic attack (N_A) is the rate-determining step in the entire reaction pathway.
View Article and Find Full Text PDFPrimary liver cancer, mostly hepatocellular carcinoma (HCC) is the most common cause of cancer-related deaths around the world. Hepatitis B virus (HBV) DNA is the dominant factor that influences the progression of HCC. In this work, a novel electrochemical sensor triggered by a sandwich hybridization reaction has been developed for the ultrasensitive detection of HBV DNA.
View Article and Find Full Text PDFThe combination of supramolecular chemistry and nanotechnology has potentially applied in the construction of biosensors, and thus improves the analytical performance and robustness of electron devices. Herein, a new sandwich-type DNA sensor was constructed for ultrasensitive determination of hepatitis B virus (HBV) DNA, a recognized marker for chronic hepatitis B. The water-soluble pillar[5]arene stabilized Pd NPs combined with reduced graphene oxide nanosheet (WP5-Pd/RGO) was synthesized and employed as supporting material for the modification of electrode surface.
View Article and Find Full Text PDFIn this work, water-soluble pillar[6]arene functionalized PdPt porous core-shell octahedral nanodendrites (WP6@PdPt PCONs) were simply synthesized and used for the fabrication of NSE immunosensor. The newest generation of macrocyclic host and biomimetic nano-enzymes have been effectively integrated to achieve the robust immobilization of signal molecules by host-guest molecular recognition and sensitively catalytic amplification of electrochemical signals. The addition of Pd and the formation of WP6@PdPt PCONs unique bimetallic nanostructure are beneficial to changing Pt-based catalyst electronic structure, accelerating the electron transport, promoting the generation of synergistic catalysis effect.
View Article and Find Full Text PDFIn this work, a novel, facile, clean synthesis of monodisperse Au nanoparticles (AuNPs) with an average diameter of 5 nm was achieved by reducing HAuCl with dihydroxylatopillar[5]arene (2HP5) in basic solution without the use of harsh reagents and/or external energy. Accordingly, toluidine blue (TB), one electrochemcial indicator, could enter into the cavity of 2HP5 to fabricate host-guest complex through strong electrostatic interaction and charge-transfer interaction, which significantly enhanced the loading quantity of TB and effectively suppressed the leaking of TB resulting in an ultrasensitive and robust electrochemical response. More importantly, the integration of 2HP5-stabilized AuNPs and Pd-decorated MnO nanocomposites (2HP5@Au-Pd/MnO) might usually obtain a novel functional-enhanced materials and lead to new properties and improving the analytical performance and robustness of electrochemical devices.
View Article and Find Full Text PDFNitrogen-doped carbon dots (N-CDs) with a quantum yield of 41 ± 3% and excellent stability were prepared and are shown to be viable probes for the determination of ferric ions, which is a strong quencher of fluorescence. The absorption peak of the N-CDs is located at 325 nm. The optimal excitation and emission wavelengths of the N-CDs are 340 nm and 430 nm, respectively.
View Article and Find Full Text PDFFoodborne pathogens such as can cause diverse illnesses and seriously threaten to human health, yet far less attention has been given to detecting these pathogenic bacteria. Herein, two morphologies of nanoceria were synthesized via adjusting the concentration of NaOH, and CeO₂ nanorod has been utilized as sensing material to achieve sensitive and selective detection of DNA sequence due to its strong adsorption ability towards DNA compared to nanoparticle. The DNA probe was tightly immobilized on CeO₂/chitosan modified electrode surface via metal coordination, and the DNA surface density was 2.
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