A comprehensive classification of amino acids is based on their structure and chemical nature. Each amino acid is assigned a three-letter or one-letter symbol. The twenty amino acids found in protein are divided into seven distinct groups. Example: Glycine. Glycine has the smallest functional group (hydrogen) of any of the α amino acids
There are different ways to classify the amino acids based on structure, chemical nature, nutritional requirement, metabolic fate, and so on.
Amino acids are termed as α-amino acids, if both the carboxyl and the amino groups are attached to the same carbon atom. The α-carbon atom binds to a side chain represented by R—, which is different for each amino acid found in proteins. Amino acids exist mostly in ionised form in the biological system.
Solutions come into immediate contact with the taste buds on the tongue. Drugs and other adjuvants are generally not palatable. To enhance the palatability and to mask the undesired taste of the drugs, sweeteners are used. Examples of sweeteners are sucrose, saccharin, aspartame, sucralose and liquid glucose.
Amino acids are a group of organic compounds containing two functional groups – amino and carboxyl. The amino group (NH 2) is the basic, while the carboxyl group (—COOH) is acidic in nature. Amino acids are the simplest unit of protein molecule, and they form the building blocks of protein structure.
These are compounds or mixtures of compounds that resist changes in the final pH upon addition of small quantities of acid or base. Hence, buffering agents are used in the liquid preparation to prevent changes in the pH upon dilution or addition of an acid or alkali. They dissolve weakly acidic or basic drug in…
The solvents usually used in the oral liquid preparations are purified water, alcohol, glycerin and propylene glycol. Purified water: Naturally occurring water exerts its solvent effect on most of the drug substances. In oral preparations, demineralized water or purified water is used. Alcohol: This is the most useful primary solvent for many organic compounds. It acts as…
Applied aspects Mucopolysaccharidosis is a hereditary disorder due to the accumulation of GAGs in various tissues. Examples are Hunter’s syndrome and Hurler’s syndrome.
Glycosaminoglycans belong to negatively charged heteropolysaccharides combined with a small amount of proteins. GAGs usually absorb large quantities of water and produce a gel-like matrix that forms the basis of a body’s ground substances. The viscous and lubricating properties of mucous secretion are caused by the GAGs. Hence, they are also known as mucopolysaccharides. GAGs…
This enhances the solubility of poorly water-soluble drugs by modifying them into their water-soluble derivatives. For example, the solubility of disodium phosphate ester of betamethasone in water is 1000 times greater than its parent compound.