A kind of bioactive ligand functionalized graphene film and preparation method thereof

Abstract

The invention discloses a bioactive ligand functionalized graphene film and a preparation method thereof. The bioactive ligand is connected to the graphene film, and the bioactive ligand is Ni-nitrilotriacetic acid ligand; the preparation method of the bioactive ligand functionalized graphene film is: transferring the graphene film to an electron microscope carrier On the Internet; use the mixed aqueous solution of potassium permanganate and alkaline compound to treat the graphene film; use nitrilotriacetic acid to activate the graphene film, and then react with nickel salt. The functional modification of graphene in the present invention can solve the hydrophobicity problem of graphene, and introduce high-density biologically active ligands by using chemical links, which can realize selective and specific binding between support membranes and biomolecules, and accurately control protein distribution. The bioactive ligand-functionalized graphene film of the present invention can directly localize or capture target biomolecules in cell lysates in future optimization, and it is expected to combine biomolecule purification and cryo-EM sample preparation into one step.

Description

technical field [0001] The invention relates to a biologically active ligand-functionalized graphene film and a preparation method thereof, belonging to the technical field of biological cryo-electron microscopy. Background technique [0002] Since its appearance in the 1970s, cryo-electron microscopy has become the most important means of structural biology research after long-term development, especially recent scientific and technological breakthroughs. Cryo-electron microscopy quickly freezes water-containing biological samples under physiological conditions into amorphous glass ice, and then uses transmission electron microscopy to observe the frozen samples, and combines image processing technology to analyze the structure of biological macromolecules, so it has the advantages of other means. unique advantages that it does not have. The revolutionary breakthrough of cryo-EM technology in instrument hardware and structural analysis software in recent years has greatly ...

AI Technical Summary

Problems solved by technology

[0004] At present, the commonly used supporting membrane material for cryo-electron microscopy is micro-sieve carbon film, which has a series of disadvantages in the field of cryo-electron microscopy, including uneven surface properties, inconsistent thickness at the edge of micro-sieve holes, and amorphous carbon skeleton at liquid nitrogen temperature. Poor electrical conductivity, poor mechanical rigidity and ductility, easy to break, etc., the gas-liquid interface of the solution film suspended in the micro-sieve has adverse effects on the structural stability, particle orientation, and distribution uniformity of biomacromolecules

Ultra-thin carbon film (thickness 3-5nm) supported by micro-sieve is also a commonly used support material for frozen sample preparation, which reduces the influence of solution gas-liquid interface on biomolecules to a certain extent, but amorphous carbon Membrane background noise is high, limiting high-resolution structural studies of smaller molecular structures

The above problems have greatly reduced the repeatability, general applicability, success rate, and uniformity of sample quality of frozen samples.

In the past few years, several research groups have been exploring frozen sample grids made of new materials, including silicon nitride micro-sieves, gold micro-sieves, graphene oxide films, etc., but they have not been widely used so far. The main reason is that These materials themselves are not ideal support membrane materials for the grid, and have problems such as poor conductivity, poor rigidity at liquid nitrogen temperature, and easy rupture, and the repeatable preparation process is not mature in practice.

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