Just adding a bit to the discussion. I learned quite a bit myself as I put this post together. Hope you all enjoy the read. I'm happy to be corrected if need be....
Molar Mass
MK-2866 (Ostarine) has a molar mass of 389.33. (
1) (
2) (
3)
The original DS Epitiostanol has a molar mass of 306.51. (
1) (
2)
The Epistane DS as we know it has a listed molar mass of 320.53 (
1)
Fun fact - water has a molar mass of 18.01 g/mol. (
1)
For a complete compositional mass breakdown of each compound, go
HERE and plug in the corresponding chemical formula seen below. I included some comparisons as well:
MK-2866 (Ostarine) = C19H14F3N3O3
Epitiostanol = C19H30OS
Epistane = C20H32OS
11-Ketotestosterone = C19H26O3
Tranavar/Trendione = C18H20O2
What we know is that successful TD drugs are suggested to need a molar mass of ~ 300 daltons (g/mol) or less to be
highly effective. (
1)
Most of the TD steroids or prohormones on the market today have a molar mass of around 300 g/mol or lower. For reference, see below.
4-DHEA/1-DHEA = 288.42 (
1)
Formestane = 302.41 (
1)
Trenavar/Trendione = 268.35 (
1)
11-Ketotestosterone = 302.41 (
1)
We also know that 500 daltons (1 dalton = g/mol) is generally considered to be the upper limiit for molar mass of a compound before it can no longer be absorbed through the skin under normal circumstances. Medical innovation is however breaking down some of those barriers. (
1) (
2)
Melting Point (MP)
The next thing we tend to look at for a candidate for transdermal drug delivery is melting point. It is generally considered that a compound should have a MP of equal to or less than 150* C. This is not a hard and fast number though as 11-Ketotestosterone has a MP of 186*C. (
1) (
2)
The MP of the discussed componds, a well as some other noted componds is listed below:
MK-2866 (Ostarine) = 70 - 74* C
Epistane = 168 - 169* C
11-Ketotestosterone = 186 - 187* C
Trenavar/Trendione = 33 - 37* C
Lipophilicity
Lipophilicity explained
It is noted that compounds that have a moderate or high lipohilic nature tend to absorb better through the
Dermis, but more specifically through the
Stratum Corneum and the
Epidermis.
I can't speak to the specific hydrophilic nature of the compounds in question. Having said that, we know that adding absorption enhancers (with moderate to high lipophilicity) will allow for easier penetration through the skin. Popular agents that are used for this enhancement are terpenes such as Limonene and Nerolidol. In fact, you will find these two enhancers (among others) in some of the top TD steroids and supplements on the market today. To better explain the process, here are some excerpts for the referenced study. (
1)
Conclusion
Both Epistane and Ostarine appear to be candidates for use in a transdermal application, with proper enhancement methods used. I can't speak to how successful they would be.
Having said that, the purpose of 17-alpha-alkylated/methylated steroids, such as Epistane, is to allow for them to bypass the destructive nature of being metabolized in the liver. As we know, 17-aa steroids are quite potent when ingested orally and I'm not sure that having one in a TD delivery system would be that much better, especially when considering the negatives of a TD delivery vehicle. Those negatives being transference (to clothes or other people), having to apply the lotion daily, as well as common issues such as rash and irritation from the TD lotion. I guess in
theory more would make it to the bloodstream through the skin but it will all end up in the same place eventually. I don't necessarily see the point...