What's wrong with my FFPE FISH?

• Place tissue block on ice for 20 mins before sectioning to enable smooth cutting.
• Regularly replace your cutting blade.
• Longer, continuous ribbons are easier to manipulate.

• Maintain water temperature of 40°C - higher temperatures melt the paraffin wax.
• Use scalpels/tweezers to manipulate the sections.
• Ensure good adhesion using positively charged slides.

• Ensure all paraffin is cleared with extra washes over a longer time period.

• Store both solution and enzyme at 2-8°C.
• Maintain temperature of water bath at 98-100°C for at least 15 minutes.
• Replace pretreatment solution after each batch (max of 20 slides per wash).
• Use ceramic jars instead of glass to maintain the temperature.
• Use plastic balls on the surface of the water bath to reduce evaporation.

• Decrease the enzyme digestion time.
• After digestion, stain with DAPI and check under microscope.
• The number of over-digested cells should be <15% of the total.

Suggested digestion times:*

• Breast: 10-40 mins
• Lung: 15-20 mins
• Ovary: 10-20 mins
• Kidney: 20-25 mins
• Colon: 20 mins
• Brain: 15-18 mins

The optimal enzyme digestion time will depend on the age of the block, tissue composition and quality of fixation. Our technical support team are able to offer further help and guidance on optimising digestion times for your tissue.

*These timings are based on independent validation carried out by CytoCell on a representative set of tissues using the CytoCell Tissue Pretreatment Kit (LPS100) and should be used for guidance purposes only.

• Increase the enzyme digestion time.
• Perform the step using a 37°C hotplate.
• Ensure that the enzyme is stored correctly.

Suggested digestion times:*

• Breast: 10-40 mins
• Lung: 15-20 mins
• Ovary: 10-20 mins
• Kidney: 20-25 mins
• Colon: 20 mins
• Brain: 15-18 mins

The optimal enzyme digestion time will depend on the age of the block, tissue composition and quality of fixation. Our technical support team are able to offer further help and guidance on optimising digestion times for your tissue.

*These timings are based on independent validation carried out by CytoCell on a representative set of tissues using the CytoCell Tissue Pretreatment Kit (LPS100) and should be used for guidance purposes only.

• Calibrate hotplate/hybridiser to ensure that the correct denaturation temperature is achieved.
• 75°C for 5 mins is recommended; however increasing the denaturation temperature up to 85°C may improve signal strength in difficult specimens.

• Calibrate hotplate/hybridiser to ensure that the correct denaturation temperature is achieved.
• 75°C for 5 mins is recommended; however increasing the denaturation temperature up to 85°C may improve signal strength in difficult specimens.