Array Tomography
While FIB/SEM offers unparalleled resolution for 3D volume reconstruction (typically with a voxel size of a few nanometers), the time-consuming milling process poses challenges for obtaining information on large volumes. In situations where 3D information is needed across a substantial volume, we have developed imaging protocols that utilize array tomography. This technique involves of serial sectioning of a resin embedded sample, and acquiring sequential images using a scanning electron microscope (SEM). Although the 3D resolution is limited to the thickness of the sections (approximately 70 nm), array tomography enables the reconstruction of volumes across large areas of samples with multi-millimeter dimensions.
At Radboudumc EMC, we provide a specialized service for array tomography, and our team of experts will assist you in designing the most suitable approach for your sample and research question. Samples can be prepared using either conventional chemical fixation or cryogenic fixation through high-pressure freezing and freeze substitution. After resin embedding, ultrathin sections are prepared using an ultramicrotome, and the serial sections are then imaged using our Zeiss Sigma 300 SEM. To ensure precise imaging and accurate 3D reconstruction, we utilize the Zeiss Atlas 5 software, which facilitates data acquisition and visualization.
We recently used array tomography to
observe the ultrastructure of the myocardium and microvasculature after infarction
in a rat heart, covering large areas of the tissue.