...the concentration of a steroid hormone in an injectable liquid can be very considerably increased by the simple ex pedient of adding to the liquid another non-toxic steroid compound.
The stereid compound can be completely neutral physiologically or it may have a mild or even a high physiblogical action which does not interfere with that of the hormone, and it may even have a hormone activity similar to that of the hormone to be injected.
The increase in solubility effected by our steroid solubilizer can be as much as 150 to 400% and even more. This increased solubility was quite unexpected and appears to be contrary to the “common ion" theory of solubility in the case of ionizing substances; for in such case it is known that ionizing compounds like salts have a reduced solubility in a liquid which already has in solution a compound having an ion in common with the salt. While steroid hormones are different substances from ionizable salts, nevertheless it was to be expected that a steroid com pound would have a lower, rather than a greater, solubility in a solvent already containing another steroid compound.
