Washing Microscope Slides and Cover Glasses
Posted: Tue Jul 20, 2021 2:46 pm
I am posting in Beginners and defining same as “first time doing something.” For those who have washed and re-used many times, maybe depending on your suggestions and tips, this thread will serve as a “sticky” in the Beginners sub-forum.
First, the same jars I use for infusions, I also use for my used slides. By definition, cover glasses go here too because they are adhered to the slides. I have the following containers: Depression Slides; Slides OIL (immersion oil; petroleum jelly; various mountants); slides NO oil; Trash (broken stuff). Into each bottle I put a few drops of dish soap and of bleach. The reason for the bleach is to kill any protozoan food chain that might appear and lead to a smelly jar in need of further cleaning. And fill each jar with 1/2 to 2/3 of water; otherwise, you will break the slides when you drop them in, glass on glass.
And finally comes Wash Day! I found a medium sized plastic basin. I also found a slightly smaller sieve/strainer/colander with smallish holes. This colander fits neatly inside the basin. For a given jar, pour out the bleach/soap/water combination. Gently pull out the slides and cover glasses by hand and lay them in the bottom of the colander. Do not empty out the jar or you will have broken slides.Now go to a sink with a deep basin where you can re-fill with clean water. Raise and lower the colander in the larger basin 10 or 15 times, gently agitating and cleaning by this kinetic motion. You don’t need to touch the slides. Then dump the soap water, and clean water, and repeat this agitation until the water runs clear.
Now it is time to dry. I use clean white cotton cloths that I buy by the bundle at Amazon. Separating any cover glasses, take one slide at a time and remove excess water with a few swipes on both sides. If you hold the slide up to the light, you will yet see cloudiness made by many small droplets that adhere. Here you must buff out each slide, both sides, with different parts of the dry cloth until the slides are shiny and clear when held up to the light.
Depending on the thickness of your cover glasses, particularly if they are < 0.17 mm, they break very easily and are very difficult to buff out clean. I recommend trashing cover glasses and not bothering with the cleaning. However, you can do it. It’s an individual decision. In my case, I did clean some because I had an extenuating circumstance. The circumstance was that I bought inferior quality cover glasses from Amsco, each laden with thousands of white particles. This is as good a time as any to say, Caveat emptor! Do NOT buy Amsco cover glasses. Buy from a professional site such as https://www.emsdiasum.com
Compared to many aspects of amateur microscopy, maybe washing slides is a no-brainer. Let’s see what useful suggestions other members have.
A consideration: When you consider that you may keep the same slides for life, if you purchased “plain vanilla” slides, would it not be better to put those aside and buy, a one time purchase only, the best slides obtainable? And what is a “best” slide? Are there differences in optical quality?
First, the same jars I use for infusions, I also use for my used slides. By definition, cover glasses go here too because they are adhered to the slides. I have the following containers: Depression Slides; Slides OIL (immersion oil; petroleum jelly; various mountants); slides NO oil; Trash (broken stuff). Into each bottle I put a few drops of dish soap and of bleach. The reason for the bleach is to kill any protozoan food chain that might appear and lead to a smelly jar in need of further cleaning. And fill each jar with 1/2 to 2/3 of water; otherwise, you will break the slides when you drop them in, glass on glass.
And finally comes Wash Day! I found a medium sized plastic basin. I also found a slightly smaller sieve/strainer/colander with smallish holes. This colander fits neatly inside the basin. For a given jar, pour out the bleach/soap/water combination. Gently pull out the slides and cover glasses by hand and lay them in the bottom of the colander. Do not empty out the jar or you will have broken slides.Now go to a sink with a deep basin where you can re-fill with clean water. Raise and lower the colander in the larger basin 10 or 15 times, gently agitating and cleaning by this kinetic motion. You don’t need to touch the slides. Then dump the soap water, and clean water, and repeat this agitation until the water runs clear.
Now it is time to dry. I use clean white cotton cloths that I buy by the bundle at Amazon. Separating any cover glasses, take one slide at a time and remove excess water with a few swipes on both sides. If you hold the slide up to the light, you will yet see cloudiness made by many small droplets that adhere. Here you must buff out each slide, both sides, with different parts of the dry cloth until the slides are shiny and clear when held up to the light.
Depending on the thickness of your cover glasses, particularly if they are < 0.17 mm, they break very easily and are very difficult to buff out clean. I recommend trashing cover glasses and not bothering with the cleaning. However, you can do it. It’s an individual decision. In my case, I did clean some because I had an extenuating circumstance. The circumstance was that I bought inferior quality cover glasses from Amsco, each laden with thousands of white particles. This is as good a time as any to say, Caveat emptor! Do NOT buy Amsco cover glasses. Buy from a professional site such as https://www.emsdiasum.com
Compared to many aspects of amateur microscopy, maybe washing slides is a no-brainer. Let’s see what useful suggestions other members have.
A consideration: When you consider that you may keep the same slides for life, if you purchased “plain vanilla” slides, would it not be better to put those aside and buy, a one time purchase only, the best slides obtainable? And what is a “best” slide? Are there differences in optical quality?