Steroid isolation , depending on context, is the isolation of chemical matter required for chemical structure elucidation, derivitzation or degradation chemistry, biological testing, and other research needs (generally milligrams to grams, but often more  or the isolation of "analytical quantities" of the substance of interest (where the focus is on identifying and quantifying the substance (for example, in biological tissue or fluid). The amount isolated depends on the analytical method, but is generally less than one microgram.  [ page needed ] The methods of isolation to achieve the two scales of product are distinct, but include extraction , precipitation, adsorption , chromatography , and crystallization . In both cases, the isolated substance is purified to chemical homogeneity; combined separation and analytical methods, such as LC-MS , are chosen to be "orthogonal"—achieving their separations based on distinct modes of interaction between substance and isolating matrix—to detect a single species in the pure sample. Structure determination refers to the methods to determine the chemical structure of an isolated pure steroid, using an evolving array of chemical and physical methods which have included NMR and small-molecule crystallography .  : 10–19 Methods of analysis overlap both of the above areas, emphasizing analytical methods to determining if a steroid is present in a mixture and determining its quantity. 
Our goals vary depending on our pursuit, depending on our need but generally speaking the same rules apply to all if we are to maximize activity and reach the productive end we truly desire. For the individual who supplements with anabolic androgenic steroids for therapeutic measures, most commonly being that of low testosterone treatment, as testosterone is needed androgen replacement is really all they will be concerned with; after all, if you’re testosterone deficient the only thing that will cure it is androgen replacement. It is the performance enhancer that will truly find understanding here to be a little more worthwhile as quality stacks and cycles will generally include steroids of both anabolic and androgenic nature and activity.
As the use of anabolic androgenic steroids will suppress natural testosterone production, with total suppression varying from steroid to steroid, in most cases the primary androgen testosterone is needed in exogenous fashion in order to maintain adequate levels in the body while the cycle is in play. For many this will be the only androgen they will need and anything else they add may be of a strict anabolic capacity; this does not mean you must add anything, some will be fine even more than fine with only testosterone; after all, it is not only highly anabolic and androgenic in nature but equal in both in-terms of makeup and action and extremely well-tolerated by most healthy adult men. For others , especially those who are really looking to grow and this is found in many bodybuilding and hardcore gym circles, multiple androgenic items may be coupled together in the same cycle with an additional possible strong anabolic in nature steroid. Prime examples of such stacks might be Testosterone/Trenbolone/ Anadrol ; with this stack you have two steroids of powerful anabolic and androgenic power and a third steroid in Anadrol, while possessing decent androgenic activity highly anabolic in nature.