Macromolecular

A macromolecule is a very large molecule, such as protein, commonly created by polymerization of smaller subunits (monomers). They are typically composed of thousands of atoms or more. The most common macromolecules in biochemistry are biopolymers (nucleic acids, proteins, carbohydrates and polyphenols) and large non-polymeric molecules (such as lipids and macrocycles). Synthetic macromolecules include common plastics and synthetic fibres as well as experimental materials such as carbon nanotubes.

Macromolecule
Large molecule

A molecule of high relative molecular mass, the structure of which essentially
comprises the multiple repetition of units derived, actually or conceptually, from
molecules of low relative molecular mass.

1. In many cases, especially for synthetic polymers, a molecule can be regarded
as having a high relative molecular mass if the addition or removal of one or a
few of the units has a negligible effect on the molecular properties. This statement
fails in the case of certain macromolecules for which the properties may be
critically dependent on fine details of the molecular structure.
2. If a part or the whole of the molecule fits into this definition, it may be described
as either macromolecular or polymeric, or by polymer used adjectivally.

The term macromolecule ( + molecule) was coined by Nobel laureate Hermann Staudinger in the 1920s, although his first relevant publication on this field only mentions high molecular compounds (in excess of 1,000 atoms). At that time the phrase polymer, as introduced by Berzelius in 1833, had a different meaning from that of today: it simply was another form of isomerism for example with benzene and acetylene and had little to do with size.

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