Quantification of n-alkanes in stratum corneum in the hereditary ichthyoses

M R Judge1, N Morse-Fisher, M Manku

  • 1Department of Dermatology, Hospitals for Sick Children, London, U.K.

Related Concept Videos

Constitutional Isomers of Alkanes02:18

Constitutional Isomers of Alkanes

Organic compounds of the same molecular formula can have different structural formulas called constitutional isomers, and the phenomenon is known as constitutional isomerism. Alkanes with four or more carbons showing multiple structures with the same molecular formula thereby exhibit constitutional isomerism.
The linear isomer of an alkane is prefixed by the term “n”; hence a linear isomer of pentane is known as n-pentane. Based on the type of branching, some of the branched isomers are given...
Nomenclature of Alkanes02:22

Nomenclature of Alkanes

In the late 19th-century, the number of new chemical compounds discovered increased tremendously. Hence, the necessity arose to develop a naming system for the systematic nomenclature of these newly discovered compounds. IUPAC (International Union for Pure and Applied Chemistry), established in 1919, sets rules for the nomenclature.
The alkane nomenclature considers the length of the carbon chain, the number, and the location of the substituent to arrive at its systematic name. The IUPAC...
Cycloalkanes02:28

Cycloalkanes

Cycloalkanes are saturated cyclic hydrocarbons with carbon atoms arranged in the form of rings. They have two fewer hydrogen atoms than the corresponding acyclic alkane; therefore, their general formula is CnH2n. The structural formulas of cycloalkanes are simplified using the line-angle representation. The regular polygons are used to represent the cycloalkane rings, with each side representing a carbon-carbon bond.
The IUPAC nomenclature of cycloalkanes follows similar rules that apply to...
Nomenclature of Alkenes02:29

Nomenclature of Alkenes

The IUPAC naming system for alkenes replaces -an- with -en- in the corresponding parent alkanes. Accordingly, a simple alkene replaces the -ane suffix of the alkane with -ene.
As per the IUPAC rules, the longest carbon chain containing the maximum number of double bonds is identified as the parent chain and is numbered such that the doubly bonded carbon atoms receive the lowest possible numbers. The location of the double bond is indicated by the number of its first carbon atom. In branched...
Degree of Unsaturation02:05

Degree of Unsaturation

The degree of unsaturation (U), or index of hydrogen deficiency (IHD), is defined as the difference in the number of pairs of hydrogen atoms between the compound and the acyclic alkane with the same number of carbon atoms. Each double bond or ring costs two hydrogen atoms compared to a saturated analog and results in one degree of unsaturation.
The degree of unsaturation for hydrocarbons is U = (2C + 2 − H) / 2, where C is the number of carbon atoms and H is the number of hydrogen atoms.
For...
Cells of the Epidermis01:24

Cells of the Epidermis

The epidermis is made of four or five layers of epithelial cells, depending on its location in the body. From deep to superficial, these layers are the stratum basale, stratum spinosum, stratum granulosum, stratum lucidum, and stratum corneum.
The cells in all these layers except the stratum basale are called keratinocytes, a type of cell that manufactures and stores the protein keratin. The keratinocytes in the stratum corneum are dead and regularly slough away, being replaced by cells from...