Intrinsic solubility refers to the drug does without any impurities in the solvent and occur dissociation or association, nor the interaction occurred when the concentration of saturated solution is one of the important physical parameters of the drug, especially for new compounds.
From the point of view of formulation, the solubility of a new drug is the first parameter that should be determined because, after understanding of the parameter, the choice of formulation dosage form and the formulation of the formulation, the process, the crystal form of the drug, the particle size and the like can be appropriately considered. In many cases, if the solubility of the oral drug is less than 1 mg / ml, the absorption problem may occur.
Obviously, this index has a certain correlation with the dissolution rate and has the same meaning. Medicilon Biomedical has a wealth of compound solubility test, the empirical solution of the compounds solubility.
Drug properties of the solubility and determination of the drug properties and solubility (intrinsic solubility) refers to the drug does not contain any impurities in the solvent does not occur dissociation or association, nor the interaction occurs when the concentration of saturated solution is the drug one of the important physical parameters, especially for new compounds is more meaningful.
Drug solution of the solubility and determination of the drug solubility of the number of values are mostly balanced solubility, the specific method of measurement is to take a number of drugs, the preparation of unsaturated solution from the saturated solution to a series of solutions, under constant temperature conditions to balance the oscillation, filtration, take the filtrate analysis, determination of the actual concentration of drugs in the solution S, and the preparation of the solution concentration c mapping.
Whether it is to determine the equilibrium solubility or the solubility of the properties, generally need to be low temperature (4 ~ 5 ℃) and body temperature (37 ℃) under the two conditions in order to drug and its preparation to consider the storage and use. If you need to further understand the impact of drug stability on the solubility, the test should also use both acidic and alkaline solvent system.
When do the determination of solubility, it should pay attention to constant temperature stirring to achieve the balance of time, different drugs in the solvent dissolution equilibrium time is different. Determination of sampling to keep the temperature and test temperature consistent and filter out undisclosed drugs, which is the main factor affecting the determination.