A C=O (a carbon double bonded to oxygen) group is a characteristic functional group present in a variety of biomolecules, including aldehydes, ketones, carboxylic acids, esters, and amides. The reagent that specifically detects a C=O group in a biomolecule is called 2,4-dinitrophenylhydrazine (DNPH).
When DNPH is added to a sample containing a molecule with a C=O group, it reacts with the C=O group to form a stable derivative called a dinitrophenylhydrazone. This reaction is often referred to as the "DNPH test" or "Brady's test."
The DNPH test is commonly used to identify the presence of aldehydes and ketones in various biomolecules, such as proteins, carbohydrates, and lipids. For example, the test can be used to identify the presence of reducing sugars, such as glucose and fructose, which are known to react with DNPH to form a yellow-to-orange-red precipitate. Similarly, the test can also be used to detect the presence of ketones, such as acetone, in body fluids like urine.
Therefore, if a biomolecule contains a C=O group in the form of an aldehyde or ketone, it will give a positive test with DNPH.
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A C=O (a carbon double bonded to oxygen) group is a characteristic functional group present in a variety of biomolecules, including aldehydes, ketones, carboxylic acids, esters, and amides. The reagent that specifically detects a C=O group in a biomolecule is called 2,4-dinitrophenylhydrazine (DNPH).
When DNPH is added to a sample containing a molecule with a C=O group, it reacts with the C=O group to form a stable derivative called a dinitrophenylhydrazone. This reaction is often referred to as the "DNPH test" or "Brady's test."
The DNPH test is commonly used to identify the presence of aldehydes and ketones in various biomolecules, such as proteins, carbohydrates, and lipids. For example, the test can be used to identify the presence of reducing sugars, such as glucose and fructose, which are known to react with DNPH to form a yellow-to-orange-red precipitate. Similarly, the test can also be used to detect the presence of ketones, such as acetone, in body fluids like urine.
Therefore, if a biomolecule contains a C=O group in the form of an aldehyde or ketone, it will give a positive test with DNPH.