05/08/2017 at 17:34 •
I have always been interested in micro fluid systems and lab-on-a-chip solutions. I love the combination of chemistry and electronics. To start with such experiments I followed the simple fabrication of complex microfluidic devices tutorial. I used ABS printer filament with a dia. of 1.75 mm to wind a small coiled type micro fluid system with one inlet and one outlet. I used a yogurt cup as a mold, added 50 g 2-component silicone (TFC silicone rubber type 15, Shore hardness 32) and placed the coil in it.
After the silicone was cured I removed the mold and cut the exceeding filament away. You can see a lot of trapped air bubbles because I didn't degas the silicone for the first experiment.
Then I left it for 48 h in acetone to remove the ABS filament. First try using my vacuum chamber to degas the silicone...
Cleaned up micro fluid system. I used a syringe for medical use to remove residual liquefied ABS. Those syringes are acetone resistant.
04/19/2017 at 17:52 •
Today I had a chat with my brother. His wife is a doctor. She told him if the patient is sweating, he or she will absorb much more medicine through the skin. This could lead to a dangerous overdose. Means for me, I need to add a galvanic skin response meter as a second sensor to my design, which is fortunately very easy to do.
04/18/2017 at 18:49 •
Based on my research on the former log I started to develop an antipyretic and anti-inflammatory drug which works within 10 seconds by absorption through the skin. I will call it Ibupromt.
I pestled three 400 mg Ibuprofen pills, put it in an Erlenmeyer flask, added 40 ml dichloromethane and let it set for at least one hour.
Then I filtered the solution off by adding piece wise another 40 ml dichloromethane to the filter cake. Re-crystallization of solids in the petri dish started immediately as dichloromethane is highly volatile.
After all dichloromethane evaporated I measured the weight of the filter cake:Assuming all ibuprofen were dissolved by the dichloromethane, I should have now 1895 mg containing 1200 mg ibuprofen left in the re-crystallized filtered solution, means I must get rid of 695 mg of other in dichloromethane dissoluble ingredients.
I dried the re-crystallized stuff for 5 hours at 70° C on a lab hot plate.As mentioned ibuprofen is practically insoluble in water. I put the re-crystallized and dried filtrate in a beaker, added 100 ml distilled water and heated it up to 70° C and stirred it for 2 hours, to remove any water-soluble remaining ingredients.
Then I filtered it off again.
Afterwards I dried the filter cake at 70° C for 5 hours and measured the weight again. I was expecting around 1200 mg, but the yield was only 700 mg. I doubt one pill really contains 400 mg ibuprofen, but I do not have time to prove that the pharmaceutical industry is cheating. The public trade supervision will do that for me.
Next I dissolved the 700 mg ibuprofen in 5 ml of 50° C warm DMSO. This happens quick, within a few seconds.
Then I filtered the solution again off directly into a brown medicine bottle. I used a quite warm place (nearby the radiator in my bathroom with floor heating; melting point of pure DMSO is approx. 19° C).
Finally I labeled the medicine bottle accordingly.
04/17/2017 at 13:38 •
Today I had headache - perfect condition for an experiment on myself. Instead of taking Ibuprofen the normal way, I dissolved it in Dimethyl sulfoxide (DMSO).
Ibuprofen is practically insoluble in water, but very soluble in most organic solvents like ethanol, acetone or dichloromethane. DMSO is an important solvent and because it increases the rate of absorption of some compounds through organic tissues, including skin, it is used in some transdermal drug delivery systems.
I used a 400 mg Ibuprofen pill and weighted it firstly: 650 mg, means 250 mg other ingredients like starch, titanium and silicon dioxide.I pestled the pill and added 10 ml warm pure ethanol to dissolve the Ibuprofen and filtered the still warm solution off.
Then I added 5 ml DMSO to the filtered solution and heated it up to 150° C using a lab magnetic stirrer with hot plate until I was sure all ethanol evaporated. I don't wanted to get drunken. Meanwhile my headache got worse.
Finally I filtered the hot solution again.
I sat down with a stopwatch, applied 5 drops of the DMSO/Ibuprofen solution to the back of my left hand and waited. After 2 minutes my headache was gone. It works!