I played a bit with making a gel with diluted formic and water. The gel can be made a number of ways but I was familiar with the easily obtained psyllium husk powder from health food stores. The gel slows transfer of liquid to the evaporative surface giving a slow release. I tested for weight loss of a sample in gel compared to open container and it appeared to have promise of a workable slow release method.
That was about the time I switched to Oxalic vaporization and I did not take the experiment to any conclusion. It appeared possible to come to a much lower cost home brew treatment than the Maqs. strips.
Water and glycerine mix quite well with formic and perhaps do not interfere with the gell forming abilities of psyllium powder.