What is the stability of a minoxidil lotion solution?

Of a study, which is unfortunately only available in Chinese, I found an abstract, which teaches us something.

The study was conducted on a 2% solution, which contains as solvents propylene glycol 10ml; water 20ml and alcohol AD 100ml. The solution was stored at 50 à 80 ° C. After a certain time, she turns dark yellow. The shelf life was recorded at 6 months.

everywhere it is pointed out the degradation by light and therefore the importance of the packaging, which must be impenetrable to light. Also the addition of sodium thiosulfate increases the stability. The solubility of this salt will be greatly determined by the amount of water present in the solution. Concrete data are published in the article "Photostability Profiles of Minoxidil solutions" in PDA J. Pharm Sci Tech. 1996, 50, pages 94-98. But this article is not available electronically.