I am going to perform a minimum inhibition concentration (MIC) assay using the broth microdilution method which will involve a 12-16 hour incubation period of the 96-well plate in a shaking incubator.

As I understand, the 96-well plates are usually sealed with a sterile adhesive film prior to incubation to prevent the liquid contents in the wells from evaporating while allowing gaseous exchange to occur. However, my university's budget is very limited and I realised that these seals are extremely expensive, so I was thinking of modifying my experiment by sealing the sides of the plates with parafilm to minimise water evaporation.

Could anybody advise me on whether my method would be any effective in preventing water from evaporating from my 96-well plates while at the same time allow some form of gaseous exchange to occur during the incubation process?

Another idea which I could think of is to purchase the non-sterile seals for a very cheap price and attempt to sterilise them myself by placing the seals in the biological safety cabinet and subjecting them to UV light for 1 hour prior to use. Could this method of sterilisation be sufficient to prevent contamination?