Using Canada Balsam for Microscope Slide Preparation

Canada Balsam is an excellent mounting medium that ensures long-lasting preservation and clarity for your specimen slides. Its high viscosity (10,000-11,000 cSt) and refractive index close to that of glass (nD = 1.5250-1.5270) make it ideal for creating durable preparations with optimal optical properties. It is also compatible with xylene, which serves as a clearing and deparaffinizing agent.

Required Materials

  • Canada Balsam: A natural exudate from conifer trees used as a mounting medium.
  • Xylene: A clearing medium that also serves to deparaffinize specimens.
  • Glass Slides: High-quality slides for mounting specimens.
  • Cover Glasses: Available in sizes ranging from 18x18 mm to 24x60 mm.



Ensure your specimen is completely dehydrated before mounting. This is crucial for the clarity and preservation of the sample.

Applying Canada Balsam:

  • Use a glass stick to apply approximately 0.05 ml of Canada Balsam to a horizontal glass slide.
  • Carefully spread the medium over the specimen to avoid air bubbles.
  • Place a clean cover glass on top, ensuring no air bubbles form.


  • Leave the slide in a thermostat set to a horizontal position.
  • Allow to dry for 30-40 minutes until the medium solidifies.

Microscopical Analysis:

  • Once dried, your specimen slide is ready for examination under a microscope.

Notes for Optimal Results

  • For the best optical quality and transparency, the mounting medium must contain the same solvent as the clearing/deparaffinizing medium used earlier. Use Canada Balsam if you have previously used xylene.
  • Utilize modern technology and appropriate instruments for sample collection and preparation.
  • Ensure all samples are clearly marked.

Safety and Handling

  • Follow safety guidelines for work and environmental protection diligently.
  • Dispose of used solutions and expired products as special waste according to national regulations.
  • Treat all tested tissue specimens as potentially infectious and adopt necessary safety measures.
  • Adhere to the product's label instructions, safety warnings, and safety data sheet recommendations.

Storage and Stability

  • Store Canada Balsam in its original, tightly sealed package at a temperature between 15°C and 25°C.
  • Avoid freezing and exposure to direct sunlight.
  • Note the manufacturer and expiration dates on the product label for safe use.

By adhering to these instructions, you ensure the preparation of high-quality, durable specimen slides for microscopy, leveraging the benefits of Canada Balsam for sample preservation and clarity.


  1. Carson, F. L., Hladik, C. (2009): Histotechnology: A Self-Instructional Text, 3rd ed., Chicago: ASCP Press
  2. Cook, D. J. (2006): Cellular Pathology, 2nd ed., Banbury: Scion Publishing Ltd.
  3. Ono, M., Murakami, T., Kudo, A., Isshiki, M., Sawada, H., Segawa, A. (2001): Quantitative Comparison of Anti-Fading Mounting Media for Confocal Laser Scanning Microscopy, 4th ed., Bloxham: Scion Publishing Ltd.