Chemical test

In chemistry, a chemical test is a qualitative or quantitative procedure designed to prove the existence of, or to quantify, a chemical compound or chemical group with the aid of a specific reagent. A presumptive test is specifically used in medical science.

Purposes

Chemical testing might have a variety of purposes, such as:

• Determine if, or verify that, the requirements of a specification, regulation, or contract are met
• Decide if a new product development program is on track: Demonstrate proof of concept
• Demonstrate the utility of a proposed patent
• Determine the interactions of a sample with other known substances
• Determine the composition of a sample
• Provide standard data for other scientific, medical, and Quality assurance functions
• Validate suitability for end-use
• Provide a basis for Technical communication
• Provide a technical means of comparison of several options
• Provide evidence in legal proceedings

Biochemical tests

• Clinistrips quantitatively test for sugar in urine
• The Kastle-Meyer test tests for the presence of blood
• Salicylate testing is a category of drug testing that is focused on detecting salicylates such as acetysalicylic acid for either biochemical or medical purposes.
• The Phadebas test tests for the presence of saliva for forensic purposes
• Iodine solution tests for starch
• The Van Slyke determination tests for specific amino acids
• The Zimmermann test for Ketosteroids
• Seliwanoff's test for differentiating between aldose and ketose sugars
• Test for lipids: add ethanol to sample, then shake; add water to the solution, and shake again. If fat is present, the product turns milky white.

Reducing sugars

• Barfoed's test tests for reducing polysaccharides or disaccharides
• Benedict's reagent tests for reducing sugars or aldehydes
• Fehling's solution tests for reducing sugars or aldehydes, similar to Benedict's reagent
• Molisch's test for carbohydrates

Proteins and polypeptides

• The Bicinchoninic acid assay tests for proteins
• Biuret reagent tests for proteins and polypeptides
• Bradford protein assay measures protein quantitative
• The Phadebas Amylase Test determines alpha-amylase activity

Organic tests

• The Carbylamine reaction tests for primary amines
• The Griess test tests for organic nitrite compounds
• The Iodoform reaction tests for the presence of methyl ketones, or compounds which can be oxidized to methyl ketones
• The Schiff test detects aldehydes
• Tollens' reagent (Silver Mirror) tests for aldehydes
• The Zeisel determination tests for the presence of esters or ethers
• Lucas' reagent is used to determine mainly between primary, secondary and tertiary alcohols.

Inorganic tests

• Barium chloride tests for sulfates
• The Beilstein test tests for halides qualitatively
• Borax bead test tests for certain metals
• The Carius halogen method measures halides quantitatively
• Chemical test for cyanide tests for the presence of cyanide, CN^-
• Copper sulfate tests for presence of water
• Flame tests test for metals
• The Gilman test tests for the presence of a Grignard reagent
• The Kjeldahl method quantitatively determines the presence of nitrogen
• Nessler's reagent tests for the presence of ammonia
• Ninhydrin tests for ammonia or primary amines
• Phosphate test for phosphate
• The sodium fusion test tests for the presence of nitrogen, sulfur, and halides in a sample
• The Zerewitinoff determination tests for any acidic hydrogen
• The Oddy test for acid, aldehydes, and sulfides

See also

• Test method
• Independent test organization

References