Preconditioning of chromatography chamber 1. #####%%%%% output "chromatography solvent" are used in line4
{"action": "optimize", "output": "chromatography solvent", "device": [""]}
Prepare chromatography solvent by mixing isobutanol, .
{"action": "prepare", "output": "", "reagent": ["chromatography solvent", "isobutanol"]}
Seal the solvent-containing chamber for at least 1 h to saturate the chamber with solvent vapors. #####%%%%% output "solvent vapors" are used in line8
{"action": "seal", "output": "solvent vapors", "time": ["at least 1 h"], "temperature": [""]}
Scissor out a strip of chromatography paper with the appropriate dimensions.
{"action": "pin", "output": "", "container": ["chromatography paper"], "reagent": ["", "solvent vapors"]}
The width of the strip depends on the number of samples to be analyzed.

The height depends on the difference in Rf values of separated compounds . #####%%%%% output "separated compounds" are used in line24
{"action": "determine", "output": "separated compounds", "device": [""]}
Draw a line 20 mm from the bottom of the strip with a graphite pencil (starting line).
{"action": "draw", "output": "", "length": ["a line"], "device": ["a graphite pencil (starting line)"]}
Microliter quantities are used to prepare spots.

In order to get a concentrated spot, the spotting can be repeated several times. #####%%%%% output "urocanic acid" are used in line20
{"action": "repeat", "output": "urocanic acid", "concentration": ["a concentrated spot"]}
In the case of urocanic acid , each spot should contain about 10 nmol of one of these compounds.
{"action": "produce", "output": "", "reagent": ["urocanic acid"]}
To develop the chromatogram, place the prepared strip into the saturated chromatography chamber . #####%%%%% output "the chromatogram" are not used
{"action": "place", "output": "the chromatogram", "container": ["the prepared strip"]}
seal the chamber
{"action": "seal", "output": "", "container": ["the chamber"], "reagent": ["separated compounds"]}
Remove the strip from the chamber when the solvent front has traveled up to about 20 mm from the top of the paper.
{"action": "remove", "output": "", "container": ["the strip"]}
Air dry the strip. #####%%%%% output "imidazolyl derivatives" are used in line30
{"action": "dry", "output": "imidazolyl derivatives", "device": [""]}
Using a spraying nozzle, spray the dried strip first with the Pauly diazo reagent until the paper becomes humid, followed by spraying the humid strip with a 10% Na2CO3 solution until spots of imidazolyl derivatives become colored (urocanic acid – orange, red).
{"action": "rinse", "output": "", "reagent": ["the Pauly diazo reagent", "imidazolyl derivatives"]}
Calculate Rf values [(distance traveled by a component)/(distance traveled by the solvent)]. #####%%%%% output "Rf values" are not used
{"action": "calculate", "output": "Rf values", "container": ["the solvent"]}