Variables: concentration Substances: 4-Formylaminoantipyrin (4-FAA) (WSJBSKRPKADYRQ-UHFFFAOYSA-N) 5-Fluoro Cytosine (XRECTZIEBJDKEO-UHFFFAOYSA-N) 2-n-Octyl-4-isothiazolin-3-on (OIT) (JPMIIZHYYWMHDT-UHFFFAOYSA-N) 4-Hydroxy-1-(2-hydroxyethyl)-2-2-6-6-tetramethylpiperidine (STEYNUVPFMIUOY-UHFFFAOYSA-N)