Limit tests are quantitative or semi-quantitative tests designed to identify and control small quantities of impurities which are likely to be present in a substance. Think of these as “pass/fail” tests to ensure chemical purity. It determines if the impurity is below the maximum allowable limit specified by the Pharmacopoeia. Definition & Logic Limit Test … Read more
In Pharmaceutical Chemistry, an impurity is any substance present in a medicinal agent other than the chemical entity itself. Even a tiny amount of impurity can make a drug toxic or reduce its shelf life. It is very essential to understand where these impurities come from for ensuring drug safety and quality. Impurities can enter … Read more
An error is the difference between the measured value and the “true” or accepted value. Even with the best equipment, some error is always present. In pharmaceutical analysis, errors can significantly impact the safety and efficacy of a drug. While errors can never be zero, they must be within the Official Limits set by the … Read more
Preparation and standardization are fundamental techniques in analytical chemistry. It is crucial to understand the principle, chemical reactions, equivalent weight calculations, and the indicators used. Equivalent weight calculation: Eq. Wt. = Molecular Weight/Valency Factor (n-factor); The n-factor varies depending on whether the substance is an acid, a base, or a redox agent. Calculation of the … Read more
In Pharmaceutical Analysis, “Standards” are the backbone of every measurement. To understand them easily, think of a Primary Standard as the “Master Key” and a Secondary Standard as a “Duplicate Key” that we check against the master. Primary Standard Primary standards in pharmaceutical analysis are highly pure substances that serve as a reference for quantitative … Read more
In the analysis of fats and oils, mathematical constants are used to normalize results to a standard sample weight (usually 1 gram or 100 grams). These are used to convert titrant volumes into the weight of the substance being measured. The Constant 56.1 (Saponification & Acid Value) The constant 56.1 is the most frequently used … Read more
The Acetyl Value is an important analytical constant used to determine the concentration of hydroxyl groups (—OH) in a fat, oil, or wax. This is particularly significant for evaluating oils like Castor Oil. It is naturally rich in 18-carbon hydroxylated fatty acid known as ricinoleic acid. Definition The Acetyl Value is defined as the number … Read more
The Ester Value is a critical analytical parameter used primarily to determine the quality and purity of waxes, fats, and essential oils. It is often studied immediately after the Acid value and Saponification value because it is mathematically derived from them. Definition The Ester Value is defined as the number of milligrams (mg) of Potassium … Read more
The Iodine Value (IV), also known as the Iodine Number. It is a fundamental analytical parameter in the analysis of fats and oils. It is a direct measure of the degree of unsaturation (number of double bonds) in a lipid sample. Definition The Iodine Value is defined as the number of grams of iodine absorbed … Read more
The Saponification Value (or Saponification Number) is a critical chemical constant used to characterize and assess the quality of fats and oils. It is essentially a measure of the average molecular weight (or chain length) of all the fatty acids present in a sample. Definition and Units: The Saponification Value is defined as the number … Read more