United States Pharmacopeia solubility

Table 4 The United States Pharmacopeia Solubility Classification...

Soluble, effervescent tablets are prepared by compression. In addition to active ingredients, they contain mixtures of acids (citric acid, tartaric acid) and sodium bicarbonate (NaHCOs) that release carbon dioxide when dissolved in water. The United States Pharmacopeia (USP) 24 includes the following seven monographs Acetaminophen for Effervescent Oral Solution Aspirin Effervescent Tablets for Oral Solution Potassium Bicarbonate Effervescent Tablets for Oral Solution Potassium Bicarbonate and Potassium Chloride for Effervescent Oral Solution Potassium Bicarbonate and Potassium Chloride Effervescent Tablets for Oral Solution Potassium and Sodium Bicarbonates and Citric Acid for Oral Solution and Potassium Chloride, Potassium Bicarbonate, and Potassium Citrate Effervescent Tablets for Oral Solution. ... 

The United States Pharmacopeia (USP) describes a group of tests used to characterize the plastic components of pharmaceutical containers and medical devices to avoid use of materials that may release water-soluble chemicals into the drug products or tissue fluids they contact. USP limits can be used to establish specifications for raw materials. 

USP 24 (1171) Phase-solubility analysis, The United States Pharmacopeia Convention, Inc... 

According to HHS-FDA guidances, the determination of the equilibrium solubility should be carried out with the shake-flask method (other methods such as acid or base titration are permitted when their ability to predict the equilibrium solubility is justified). The experiments should be carried out at a temperature of 37 1°C. Further, a sufficient number of pH conditions should be chosen to cover the pH range of 1-7.5 and each determination should be carried out at least in triplicate. The buffer solutions given in the United States Pharmacopeia (USP) are appropriate for the tests, but other buffers are also allowed for these experiments. The pH value of each buffer solution should be checked before and after each experiment. Degradation of the API due to pH or buffer composition should be reported together with other stability data. 

For very dilute solutions, solubility is often expressed in units of parts per million (ppm), which is defined as the quantity of solute dissolved in 1,000,000 equivalent units of solution. As long as the same unit is used for both solute and solvent, the concentration in parts per million is equivalent to the weight, volume, or weight-volume percentages multiplied by 10,000. The descriptive terms of solubility that is expressed in units of parts of solvent required for each part of solute can be found in each edition of the United States Pharmacopeia (Table 1). 

Considerable interest has been shown in poly(ethylene oxide) for diverse applications in food, drug, and cosmetic products. Such uses fall within the scope of the Federal Food, Drug, and Cosmetic Act. The U.S. Food and Drug Administration (FDA) has recognized and approved the use of poly(ethylene oxide) for specific food and food packaging uses. USP/NF grades of Polyox water-soluble resins (The Dow Chemical Co.) that meet all requirments of the United States Pharmacopeia/National Formulary (USP/NF) are available for pharmaceutical applications (105). 

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