Quantifoil® porous carbon membrane

Quantifoil is a porous support membrane that is precisely arranged with meshes of various sizes and shapes. Compared with ordinary porous carbon film, this kind of support film has more advantages in transmission electron microscope (TEM) grid and low energy electron point source microscope (LEEPS). The fixed geometry of Quantifoil porous carbon film facilitates automated operation on a transmission electron microscope (TEM), which is basically infeasible for ordinary carbon films. Quantifoil carbon support membrane has a large pore surface area and is often used to reduce sample thickness and reduce distortion caused by interference of the support membrane. Quantifoil porous carbon film for transmission electron microscopy (TEM) Porous film can be used to support ultra-thin carbon film, or directly as a carrier for larger samples (such as micron powder). This is very important in electron diffraction (ED), electron energy loss spectroscopy (EELS), electron energy loss spectroscopy imaging and dark field imaging. This kind of film can also be applied to the study of material nano-characteristics, such as the study of the free suspension of biological macromolecule complexes on carriers. The surface characteristics of Quantifoil porous carbon support grid, especially the wettability, need to be adjusted according to user requirements. Like other carbon membranes, untreated Quantifoil carbon membranes will gradually lose their hydrophilic properties over time (new carbon membranes generally have better hydrophilicity). ◎ Round hole: Quantifoil round hole carbon film is more suitable for low-temperature transmission electron microscope (TEM), because the round hole is more helpful to form a uniform thickness of ice. The choice of hole spacing depends on the required magnification and whether the supporting membrane blot is placed in the final image. If the diaphragm is placed in the final image, then the image quality assessment is easier because the diaphragm has a much larger power spectrum than the isolated ice layer. ◎ Square hole: Quantifoil square hole diaphragm has a small grid line width, suitable for transmission electron microscope (TEM) analysis. The thickness of the carbon film here is too thin to cover the grid spacing, nor can it provide good support for the X-ray energy spectrum analysis area. Quantifoil now provides porous membranes with "standard, stock" mesh sizes, mainly 200, 300, 400, and 100x400 meshes, made of copper, nickel, gold and rhodium-plated copper.