Main observation and conclusion DNA circuits have been designed for implementation of various functions based on DNA strand displacement in cell-free settings,but their capabilities in biological environments remain l...Main observation and conclusion DNA circuits have been designed for implementation of various functions based on DNA strand displacement in cell-free settings,but their capabilities in biological environments remain limited.In this work,we report framework nucleic acid(FNA)-based circuits enabling intracellular logic computation for mRNA imaging.FNAs as rigid scaffolds enable to deliver our built DNA circuits into cells without aid of transfection reagents,evading a time-consuming and tedious process prior to analysis,and the pendant duplex DNA designed at one vertex of FNA as gate is suitable for four-way strand exchange,minimizing crosstalk with other nucleic acids in the cellular milieu.We demonstrated that such FNA-based circuits can operate both in vitro and in vivo logic computation,including OR and AND logic gates.Moreover,in situ mRNA imaging was also realized by exploiting native mRNA as scaffolds to bind multiple FNA-based gates for the enhanced signal-to-background ratio.We hope that this FNA-based circuit can be applied for disease diagnosis,facilitating the development of biomedicine.展开更多
A low-cost and high-activity catalyst for oxygen evolution reaction （OER） is the key to the water splitting technology for hydrogen generation. Here we report the use of three solvents, DMF, ethanol and glycol, in t...A low-cost and high-activity catalyst for oxygen evolution reaction （OER） is the key to the water splitting technology for hydrogen generation. Here we report the use of three solvents, DMF, ethanol and glycol, in the solvothermal synthesis of three nano-catalysts, Co3（VO4）2-I, Co3（VO4）2-II, and Co3（VO4）2-III, respec- tively. Transmission electron microscope shows Co3（VO4）2-I, II, and III exist as ultrafine nanosheets, ultrathin nanofilms, and ultrafine nanosheet-comprised microspheres, respectively. These Co3（VO4）2 catalysts exhibit OER electrocatalysis, among which the Co3（VO4）2-II shows the lowest onset overpotential of 310 mV and only requires a small overpotential of 330 mV to drive current density of 10 mA/cm^2. Due to their high surface free energy, the ultmthin nanofilms of Co3（VO4）2- II exhibits a good immobilization effect with the high electrocatalytic activity for OER.展开更多
基金This work was supported by the National Key Research and Development Program of China for International Science&Innovation Cooperation Major Project between Governments(No.2018YFE0113200)the National Natural Science Foundation of China(Grant Nos.21722502,22074041)+1 种基金the Shanghai Rising-Star Program(No.19QA1403000)the Shanghai Science and Technology Committee(STCSM)(Grant No.18490740500).
文摘Main observation and conclusion DNA circuits have been designed for implementation of various functions based on DNA strand displacement in cell-free settings,but their capabilities in biological environments remain limited.In this work,we report framework nucleic acid(FNA)-based circuits enabling intracellular logic computation for mRNA imaging.FNAs as rigid scaffolds enable to deliver our built DNA circuits into cells without aid of transfection reagents,evading a time-consuming and tedious process prior to analysis,and the pendant duplex DNA designed at one vertex of FNA as gate is suitable for four-way strand exchange,minimizing crosstalk with other nucleic acids in the cellular milieu.We demonstrated that such FNA-based circuits can operate both in vitro and in vivo logic computation,including OR and AND logic gates.Moreover,in situ mRNA imaging was also realized by exploiting native mRNA as scaffolds to bind multiple FNA-based gates for the enhanced signal-to-background ratio.We hope that this FNA-based circuit can be applied for disease diagnosis,facilitating the development of biomedicine.
文摘A low-cost and high-activity catalyst for oxygen evolution reaction （OER） is the key to the water splitting technology for hydrogen generation. Here we report the use of three solvents, DMF, ethanol and glycol, in the solvothermal synthesis of three nano-catalysts, Co3（VO4）2-I, Co3（VO4）2-II, and Co3（VO4）2-III, respec- tively. Transmission electron microscope shows Co3（VO4）2-I, II, and III exist as ultrafine nanosheets, ultrathin nanofilms, and ultrafine nanosheet-comprised microspheres, respectively. These Co3（VO4）2 catalysts exhibit OER electrocatalysis, among which the Co3（VO4）2-II shows the lowest onset overpotential of 310 mV and only requires a small overpotential of 330 mV to drive current density of 10 mA/cm^2. Due to their high surface free energy, the ultmthin nanofilms of Co3（VO4）2- II exhibits a good immobilization effect with the high electrocatalytic activity for OER.
