Angiotensin-converting enzyme 2(ACE2) is not only an enzyme but also a functional receptor on cell membrane for severe acute respiratory syndrome coronavirus 2(SARS-CoV-2). Here, the activity of ACE2 in single living ...Angiotensin-converting enzyme 2(ACE2) is not only an enzyme but also a functional receptor on cell membrane for severe acute respiratory syndrome coronavirus 2(SARS-CoV-2). Here, the activity of ACE2 in single living cell is firstly determined using a nanokit coupled electrospray ionization mass spectrometry(nanokit-ESI-MS). Upon the insertion of a micro-capillary into the living h ACE2-CHO cell and the electrochemical sorting of the cytosol, the target ACE2 enzyme hydrolyses angiotensin II inside the capillary to generate angiotensin 1-7. After the electrospray of the mixture at the tip of the capillary, the product is differentiated from the substrate in molecular weight to achieve the detection of ACE2 activity in single cells. The further measurement illustrates that the inflammatory state of cells does not lead to the significant change of ACE2 catalytic activity, which elucidates the relationship between intracellular ACE2 activity and inflammation at single cell level. The established strategy will provide a specific analytical method for further studying the role of ACE2 in the process of virus infection, and extend the application of nanokit based single cell analysis.展开更多
Controlled synthesis of asymmetrical gold nanokites was realized by reducing HAuCl4 with polyvinyl alcohol （PVA） in PVA-sodium dodecyl sulfate （SDS） aggregations aqueous solution at room temperature without any ad...Controlled synthesis of asymmetrical gold nanokites was realized by reducing HAuCl4 with polyvinyl alcohol （PVA） in PVA-sodium dodecyl sulfate （SDS） aggregations aqueous solution at room temperature without any addi- tional reducing agents. The crystal structures, optical property and growth process of the gold nanokites were inves- tigated by X-ray diffraction （XRD）, Vis-NIR spectrum and transmission electron microscope （TEM）. HAuCl4 con- centration dramatically influenced the morphologies of the products. When HAuCl4 concentration was increased from 0.5 mmol·L^-1 to 2.2 mmol·L^-1, the products changed from network-like nanostructures to nanokites, nanoleaves and microplates. SDS was indispensable for the formation of gold nanokites and without SDS su- per-branched structures became the dominant products.展开更多
基金supported by Ministry of Science and Technology of China(No.2017YFA0700500)the National Natural Science Foundation of China(Nos.22025403 and 21974060)+1 种基金Kuanren Talents Program of the Second Affiliated Hospital of Chongqing Medical UniversityYoung and Middle-aged Senior Medical Talents Studio of Chongqing。
文摘Angiotensin-converting enzyme 2(ACE2) is not only an enzyme but also a functional receptor on cell membrane for severe acute respiratory syndrome coronavirus 2(SARS-CoV-2). Here, the activity of ACE2 in single living cell is firstly determined using a nanokit coupled electrospray ionization mass spectrometry(nanokit-ESI-MS). Upon the insertion of a micro-capillary into the living h ACE2-CHO cell and the electrochemical sorting of the cytosol, the target ACE2 enzyme hydrolyses angiotensin II inside the capillary to generate angiotensin 1-7. After the electrospray of the mixture at the tip of the capillary, the product is differentiated from the substrate in molecular weight to achieve the detection of ACE2 activity in single cells. The further measurement illustrates that the inflammatory state of cells does not lead to the significant change of ACE2 catalytic activity, which elucidates the relationship between intracellular ACE2 activity and inflammation at single cell level. The established strategy will provide a specific analytical method for further studying the role of ACE2 in the process of virus infection, and extend the application of nanokit based single cell analysis.
基金Project supported by the National Natural Science Foundation of China （No. 20871059） and Jiangsu Provincial Post Graduate Innovation Plan （No. CX08B_118Z）.
文摘Controlled synthesis of asymmetrical gold nanokites was realized by reducing HAuCl4 with polyvinyl alcohol （PVA） in PVA-sodium dodecyl sulfate （SDS） aggregations aqueous solution at room temperature without any addi- tional reducing agents. The crystal structures, optical property and growth process of the gold nanokites were inves- tigated by X-ray diffraction （XRD）, Vis-NIR spectrum and transmission electron microscope （TEM）. HAuCl4 con- centration dramatically influenced the morphologies of the products. When HAuCl4 concentration was increased from 0.5 mmol·L^-1 to 2.2 mmol·L^-1, the products changed from network-like nanostructures to nanokites, nanoleaves and microplates. SDS was indispensable for the formation of gold nanokites and without SDS su- per-branched structures became the dominant products.
