To extend the approach of using RNA aptamers as transient protective groups for the synthesis of novel small-molecule drug derivatives from the existing aminoglycosides, we incorporated 2'-5' phosphodiester backbone modification in a structurally known neomycin RNA aptamer and studied the binding of a series of aminoglycosides using isothermal calorimetry (ITC) and molecular dynamics (MD) simulation. Experimental characterization of amikacin, a commercially available and widely used aminoglycoside for treating bacterial infections, shows that the aptamer A1 with a 2'-5' linkage between G15 and U16 exhibits a sevenfold increase in binding affinity with a lower binding energy compared to the native aptamer. Molecular dynamics (MD) simulation studies rationalize that this noncanonical linkage generates a narrower binding pocket by creating a superspiral RNA helical structure, which improves the ligand's fit in the binding pocket.
View Article and Find Full Text PDFCurrently, real time monitoring of chemical substances in vivo and in vitro has gained enormous attraction, and many researches reports have been focused on the design and construction of high-performance biosensor devices. In this work, a high-performance sensor was constructed by taking advantage of the excellent electrochemical activity and high-index facets of Au-Pd nanocubes and the large surface of rGO. Glassy carbon electrodes (GCEs) were modified by both Au-Pd nanocubes and rGO nanocomposites via physical adsorption.
View Article and Find Full Text PDFRecently, great efforts have been made to use biosensors for the early diagnosis of cancer. Specifically, using a biomarker to detect HO in physiological conditions is of great significance for understanding the signal transduction pathways and achieving early cancer diagnosis. In this work, we report an innovative HO sensor that was fabricated by trimetallic AuPtPd nanocomposites platform on reduced graphene oxide (rGO) nanosheets with the modification of the rGO and trimetallic AuPtPd nanoparticles on a glassy carbon electrode (GCE) by physical adsorption.
View Article and Find Full Text PDFThe flourish of nanotechnology has brought new vitality to the research and development of electrochemical sensing materials. In this work, we successfully synthesized Nano Au and Pt alloy microspheres decorated with reduced graphene oxide (RGO/nAPAMSs) by a simple, facile, and eco-friendly one-step reduction strategy for the fabrication of highly sensitive nonenzymatic HO sensing interfaces. Energy-dispersive X-ray spectroscopy mapping (EDX mapping), energy-dispersive X-ray spectroscopy analysis (EDX), transmission electron microscopy (TEM), Fourier transform infrared spectrum (FT-IR), and X-ray diffraction spectrum (XRD) were employed to characterize RGO/nAPAMSs from a microscopic perspective.
View Article and Find Full Text PDFAn innovative epinephrine sensor was fabricated by integrating tetrahexahedral (THH) Au-Pd core-shell nanocrystals on reduced graphene oxide (rGO) nanosheets. Furthermore, the nanocomposites combined the large specific areas of rGO with the high-index facets and excellent electrocatalytic activity of the THH Au-Pd nanocrystals, and the nanocomposites were an essential adapter for detecting epinephrine. In the present work, transmission electron microscopy (TEM), Fourier transform infrared spectroscopy (FTIR) and X-ray diffraction (XRD) were used to identify and characterize these unique nanocomposites, and the results revealed that a unique THH Au-Pd/rGO core-shell nanostructure was synthesized successfully.
View Article and Find Full Text PDFGraphene sheets are a sp-hybridized carbon material that offer extraordinary electrical conductivity and excellent thermal and mechanical properties. They are expected to find use in a wide variety of applications. In this study, a new novel electrocatalyst, a Pb nanowires-Au nanoparticles nanocomposite decorated with reduced graphene oxide (rGO-Pb NWs-Au NPs), was successfully synthesized by an effective and simple approach.
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