Cleaning microscope slides
Answer reviewed 27 February 2023
Microscope slides are best handled carefully by holding the edges. Finger marks and other artefacts such as dust and scratches can affect the quality of the image viewed on the slide. Slides that are scratched should be disposed of into a glass/sharps bin
Cleaning dry or wet mount slides for re-use
- Carefully remove coverslip and discard into a glass/sharps bin.
- Remove sample e.g., onion or “e” slides, and discard non-hazardous biological samples to general refuse.
- Wash slide in warm soapy water.
- Rinse well in running water.
- Blot dry on low-lint tissue (Kimwipes®).
- Dip into methylated spirit.
- Polish with a clean dry lint-free tissue.
- Store in a clean container.
Caution: Methylated spirit is flammable1. Science ASSIST advises that glass slides not be stored in methylated spirit in school teaching laboratories.
Cleaning new slides prior to use
New slides may have dirt or grease on them. To remove: follow procedure as for used slides outlined above (steps 3-8).
Cleaning prepared slides with permanently mounted coverslips
- Using low-lint tissue (Kimwipes®) carefully and gently clean marks with a drop of methylated spirit, taking care not to use excess which may affect the opacity and adhesion of the cover slip mounting medium.
Slides with heat fixed smears and no coverslips
Heat fixed smears are difficult to clean so are not reused and should be disposed of with broken glass into a glass/sharps bin.
Low-lint tissue (Kimwipes®) is available from Science Suppliers. See our list of School science suppliers.
References and further reading
1 ChemSupplyAustralia. (2021). ChemSupplyAustralia business unit, Search Results, Methylated Spirits (95% IMS). Retrieved from ChemSupplyAustralia: https://shop.chemsupply.com.au/search?ProductSearch=methylated%20spirit
Simulab Testing Laboratory, LabTech Training. (n.d.). Cleaning and Handling Microscope Slides. Retrieved from Study Notes: http://simulab.ltt.com.au/4/laboratory/studynotes/SNCleanMicroSlides.htm