The Wolfson Bioimaging Facility houses a range of sample preparation equipment to support both routine and specialised EM applications.
Each EM application relies on samples undergoing specialised processing steps prior to image acquisition. We can offer sample processing as a paid for service provided by our support team or users can learn the techniques required to process their specimens independently. We are happy to discuss the costs associated with each processing route.
Timescales for processing workflows vary depending on precise requirements and the numbers of samples entering the workflow but, as a guide, specimens can usually be processed and embedded for TEM by facility staff within two weeks. Due to the high demand for our ultramicrotomes and microscopes, preparation of ultrathin sections may take 2-3 weeks and acquisition of TEM images up to 2 weeks.
- Standard TEM samples are prepared by manual fixing, dehydrating, embedding, staining and sectioning. We have a range of ultramicrotomes available in a dedicated sectioning room (Leica EM UC6, EM UC7 RT with IC80HD camera, Reichert Ultracut S).
- Immunostaining applications usually require sectioning with a cryo-ultramicrotome (Leica EM UC7 with FC7 Cryo attachment). The dedicated temperature and humidity controlled room housing this ultramicrotome facilitates CEMOVIS, frozen hydrated sectioning.
- Improved ultrastructural preservation can sometimes be achieved with rapid freezing for which we have a high pressure freezer (Leica EMPACT2 + RTS) and freeze substitution equipment (Leica AFS2 + FSP). Tissue samples can also be preserved by rapid freezing with a dedicated biopsy gun system.
- For SEM, samples are first fixed and dehydrated then subjected to further drying either by solvent evaporation or, more routinely, using a critical point dryer (Leica CPD300) followed by applying a conductive metal coating with a sputter coater (Emitech K757X or Quorum Q150RES). Alternatively, we can coat with carbon (Leica ACE600 and Edwards306).
- For cryo-TEM we have a Leica EM GP Plunge freezer.
- For cryo-SEM we have a Gatan Alto cryoSEM attachment.