Question

what is the chemical composition of the fingerprints (write 400 words)

Answer 1

Chemical composition of fingerprints include mainly: lipids, water, amino acids and proteins and some minerals in form of inorganic ions. In addition to these, fingerprints also have saponins, organic acids, esters, sterols, vitamins and volatile oils. The long chain carboxylic acids such as palmitic acid and steric acid makes major part of the fingerprints in children. The fingerprints in children are rich in acids having chains of 12-26 carbon atoms. The fingerprints from adults also have acids, though in lower amount as compared to that present in the fingerprints of children. The fingerprints of adults have esters of carboxylic acids as well.

Lipids in fingerprints are present in form of oil and fats. They may have saturated or unsaturated fatty acid chains. Phospholipids, that are the triglycerides with phosphate group, are also present in fingerprints. Presence of lipids in fingerprints allows to raise them with processes that use lipid reactivity. Being monomers of proteins, amino acid are also present in fingerprints. Presence of amino acid in fingerprints can be confirmed with help of ninhydrin test. Ninhydrin is the chemical that changes its color from yellow to dense purple as it reacts with amino acids.

As of now, presence of total 30 saponins has been confirmed in fingerprints. Saponins are steriods that react with water. The chemical composition of fingerprints of children is different from that of adults. Mostly, the fingerprints of kids disappear more quickly that the fingerprints of adults. This represents different chemical composition of these two. The quicker disappearance of fingerprints of children can be attributed to the presence of more amount of volatile oil in them. Sterols of fingerprints are mostly cholesterols. It is present in fingerprints of both children and adults. Since fingerprints are made of sweat, they may get the cholesterol from epidermis of the skin. There is higher cholesterol amount in the fingerprints of children than that of the adults. Besides age, other factors also determine the chemical composition of the fingerprints. For example: the fingerprints of smokers exhibit presence of tobacco as these people hold the cigarettes with fingers. Even, the passive smokers could have tobacco in their fingerprints due to exposure to the tobacco smoke.

So, age, lifestyle, surroundings and genes all together determine the chemical composition of the fingerprint of individuals. Though, the basic components remain same in all of them.