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. 
Many people who supplement with this bronchodilator will slowly ramp down over a period of time, steadily dropping the dose every few days until it is discontinued altogether. There is truly no need for such a method as it is by-large overkill and provides no strategic advantage. No, you do not want to discontinue use cold turkey, all you need to do is simply drop down to your original Clenbuterol dosage. While many women may have begun at 20mcg per day most, including women and men will find 40mcg per day for 7-14 days to be perfect and once this period has passed simply discontinue use until your next diet is at hand.