Histology and Sample Prep
Comprehensive histology and sample preparation support for light and fluorescence microscopy applications.
Overview
SLIM provides access to a fully equipped histology laboratory supporting sample preparation, tissue processing, embedding, sectioning and staining for a wide range of biological applications.
Histology & Sample Preparation
- Paraffin wax and resin sample preparation
- Cryostat sectioning Routine histology workflows
- Light microscopy sample preparation
- Immunohistochemistry and staining
- Consultation and workflow optimisation
Sample Preparation Guidelines
Sample preparation can have profound impacts on the resulting image quality.
Fluorophore and staining selection
The information you would be able to obtain / extract from your samples it will be highly dependable on what type of labelling and staining is applied (or what is possible/feasible) and which microscope(s) will be used in your project. Therefore labelling has to be performed with considerations of which microscopy techniques will be used. With this, if you aim to image multiple components of the sample, you will need to consider the fluorophores and stains you combine. For example, filter-based imaging techniques have limited segregation of wavelengths meaning combinations are relatively narrow. For confocal, and spectral unmixing, the fluorophore selection can be more closely packed and allow for more fluorophores to be used in the same sample.
If imaging with STORM (Stochastic Optical Reconstruction Microscopy), a super-resolution technique, a maximum of 3 fluorophores can be used on our system (488, 568, and 647 nm). This combination is possible but due to the complexities of the technique, feasibility tests are recommended. Specialised buffers are needed and testing multiple buffers fro the project is advisable.
When considering co-localisation or super resolution techniques the use of fiducials (special markers) are recommended. This allows for channel alignment where small shifts between colours occur. Fluorescent beads allow for registration of channels for high precision localization.
Sample format
Knowing the best way to prepare your sample requires knowing the type of data you want to extract and the type of microscope you’re going to use. The position of objectives also impacts the type of sample format that can be accepted and the sample holders present impact the format (slide, petridish, or multiwell plate) that can be held onto the microscope stage. If you require any sample format help, please contact the SLIM team who can help demonstrate sample preparation ideas for getting your sample microscope ready.
Coverslips and thin bottom multiwell dishes
To achieve high resolution imaging, typically a short working distance objective is required. This means that the objective must be very close to the sample to be able to focus on the sample. To do this, 1.5# coverslips are recommended. If thicker coverslips or slides are used, high resolution and high magnification imaging cannot be achieved. For TIRF imaging, only glass can be used to achieve the critical angle. For SIM imaging, high precision coverslips (1.5H#) are recommended. Utmost care must be taken when bringing samples to the microscope. Ensure that coverslip surfaces remain clean and free from contamination, including PBS salt residues, excess mounting medium, nail varnish and or fingerprints. Contaminated samples can compromise image quality and potentially damage microscope objectives.
In the case of cell culture, many cell types require plastic rather than glass for adhesion. Thin plastic bottom multiwell dishes can be purchased to enable high resolution imaging. Please contact a member of the SLIM team who can advise you on available suppliers.
There are also 35mm glass bottom dishes available. SLIM keep a stock of these if users wish to trial small batches rather than buying the dishes in bulk.
Live of fixed samples, and mounting media
Please let SLIM know if you are planning to image live cells. You will be required to obtain a Biological Risk Assessment (BARA) signed off by your biological safety officer. The BARA will have to include the transport, the microscopy room location and inactivation-decontamination method in case of spill.
Please be aware that fixation processes could alter samples, therefore we recommend careful consideration in the choice of fixatives; e.g. mitochondria, ER, etc. are susceptible to fixatives. Likewise, mounting media could interfere with the staining, and samples could change over time, despite the assumption that mounting media should preserve the staining. Also the refractive index of the mounting media, or sample has to be taken into consideration when performing super resolution microscopy (SIM, Airyscan).
Available Equipment
Leica TP1020 Tissue Processor
- Automatic tissue processor
- Fixation, dehydration, and infiltration of histological tissue samples
- Compatible with fixatives, alcohols, solvents, and paraffin wax
Leica EG1150 Embedding Centre
- Modular tissue embedding system
- Leica EG1150 C cold plate
- Leica EG1150 H heated paraffin dispensing module
Leica RM2245 Microtome
- Semi-motorised rotary microtome
- Routine sectioning of histological wax blocks
- Micron-thickness sectioning
Leica RM2125RT Microtome
- Microtome for sectioning histological wax blocks
- Routine micron sectioning workflows
Epredia Cryostar NX70 Cryostat (x2)
- Cryostat for frozen tissue sectioning
- Serial section production
- Automated cutting features
- Ergonomic design
- Micron section preparation
Leica VT1000S Vibratome
- Vibrating blade tissue sectioning
- Maintains tissue morphology
- Preserves enzyme activity and cell viability
Supported Applications
- Histological tissue processing
- Frozen tissue sectioning
- Immunohistochemistry
- Paraffin and resin embedding
- Tissue clearing
Training & Support
SLIM staff provide support for sample preparation workflows, histological processing, staining techniques, and optimisation of imaging-ready samples.
Contact
For histology, staining, or sample preparation support, please contact:
Ian Ward – Senior Technical Specialist
Lizzie Ison – Senior Technical Specialist
To request a quote for grant submissions contact: Robert Markus and Seema Bagia