The composition of a commercial sample of aspirin, also known as acetylsalicylic acid, typically consists of the active pharmaceutical ingredient API and various excipients such as binders, fillers, and coatings. The exact composition may vary depending on the manufacturer and specific formulation.Liquid chromatography analysis, such as high-performance liquid chromatography HPLC , can be used to determine the concentrations of impurities in a commercial aspirin sample. Impurities may include degradation products, residual solvents, and other related substances.The specific concentrations of impurities in a commercial aspirin sample will depend on the quality control measures employed by the manufacturer and the storage conditions of the product. In general, the impurity levels should be within the acceptable limits set by regulatory agencies such as the United States Pharmacopeia USP or the European Pharmacopoeia EP .For example, the USP sets limits for the following impurities in aspirin:1. Salicylic acid: Not more than 0.15%2. Any individual unspecified impurity: Not more than 0.10%3. Total impurities: Not more than 0.30%To determine the exact concentrations of impurities in a specific commercial aspirin sample, a laboratory analysis using liquid chromatography would need to be performed.