Specimen preparation is a multi-step process, where each stage plays a crucial role in preparing a sample for examination. Minimising contamination during the embedding stage is essential in producing clean, high-quality sections for microscopy, which is critical for diagnostic accuracy. There are a number of factors that can affect the quality of samples, let’s take a look at how we can curb contamination…
A Clean Workspace
It is essential to clean the embedding station, forceps and tools after each use and remove any wax residue and tissue debris. Proactively using paraffin repellents helps to minimise time spent cleaning, whilst wax removal sprays remove any residue oil and greases. In addition, it is important to check that embedding moulds are clean prior to use. Using a mould release spray can help to reduce wax buildup. If contamination is a concern disposable moulds may be an effective alternative. It’s also important to check and remove any debris from the wax reservoir.
Wearing the correct clothing in the lab, including clean gloves and a lab coat, helps to minimise the introduction of contaminants. Avoid loose clothing and jewellery that may shed fibres or debris.
Proper Tissue Handling
Before beginning the embedding process, it is important to inspect tissue samples for foreign objects and to remove any with clean forceps. To reduce the risk of cross-contamination, samples should be handled one at a time to avoid the mixing of tissue fragments.
The Right Tools
Heated forceps are a great addition to the workspace, enabling accurate orientation in the wax. Heated forceps are available as both stand-alone systems or as an integrated feature within some embedding centres, including our Slee MPS/P2 Embedding Centre. While helping to maintain a consistent temperature, the heated functionality also prevents wax from sticking to the tool, minimising downtime spent removing wax buildup. Tissue tampers aid in specimen orientation, they ensure the sample is evenly distributed and tightly compacted within the embedding media. Getting the orientation right first time avoids any unnecessary repositioning and risk of contamination.
Fresh Embedding Medium
Reusing old wax can introduce impurities into the tissue block, regularly filtering the wax helps to remove any debris. Using new wax when required is optimal in keeping contamination to a minimum. High quality wax, such as the UltraPlast wax, ensures superior quality sections every time.
Maintenance
In addition to regularly cleaning the embedding centre, it is importance to check that all parts are functioning correctly. Solmedia offer a range of maintenance packages, including equipment service options. Proactively servicing your equipment minimises the risk of breakages and downtime.
The Final Check
Before moving onto the next step in specimen preparation it is important to carry out a final inspection of the paraffin wax block to ensure no debris or foreign objects are present.
Adhering to these practices helps to minimise contamination, produce cleaner tissue blocks and improve the overall quality of slides for microscopic examination.