Background
I’ve been doing tissue culture work on different plants and had constructed a sterile glove box in which I’d be able to work in an environment free of organisms that could contaminate the cultures.
The concept is that the tissue/explants are placed inside the box and the UVC germicidal light turned on once the lid is locked shut. This will eliminate the contaminants (bacteria, viruses, mold) in the inside air and create a seal that won’t allow the life-filled outside air in. I shut the UVC light off after 3-4 minutes of being on before working, as the light will damage my eyes. I then sterilize the surface of the explants for clean plating, allowing for a successful callus induction.
Here’s what I’ve come up with…
The Problem
Some of the cultures have been becoming contaminated by mold spores. Just for fun I let them run wild for over a month…
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The seal created by the gasket in the lid is leaking. This is caused by working with the gloves creating both negative and positive pressure leading to outside air entering the box.
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The germicidal UVC light isn’t killing everything.
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My sterilization technique for the explants needs to be improved.
My guess is that it’s either or both of the first two. I know for sure that the light works to some extent cause I can smell ozone, and I know of the leak cause I can smell it once I begin working but not before I start. I can determine if it’s also the third by eliminating the first two.
The Solution
Convert it into a filtered positive pressure system that will constantly blow sterile air into the box and through an exhaust port on the bottom. Even if there’s a leak, nothing can get in cause filtered air is always being pushed out.
I will be keeping this thread updated as the project progresses… Feel free to coment and ask questions! Cheers! 
