Macromolecules

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The literal definition of the term macromolecule implies any large molecule, typically understood to be 1000 Daltons or greater. In the context of science and engineering, the term may be applied to conventional polymers and biopolymers (such as DNA or proteins) as well as non-polymeric molecules with large molecular mass such as lipids or macrocycles. Other large atomic networks, such as metallic covalent networks or fullerenes, are not generally described as macromolecules. The term macromolecule was coined by Nobel laureate Hermann Staudinger in the 1920s.

Usage

The use of the term macromolecule varies subtly from discipline to discipline. From the strict perspective of chemistry, a "molecule" is comprised of a number of atoms linked by covalent bonds. In biology and biochemistry, however, the term macromolecule may also refer to aggregates of two or more macromolecules held together by intermolecular forces rather than covalent bonds but which do not readily dissociate. [1]

According to the recommended IUPAC definition the term macromolecule as used in polymer science refers only to a single molecule. For example, a single polymeric molecule is appropriately described as a "macromolecule" or "polymer molecule" rather than a "polymer", which suggests a substance composed of macromolecules. [2].

References

  1. van Holde, K.E. Principles of Physical Biochemistry Prentice Hall: New Jersey, 1998
  2. Glossary of Basic Terms in Polymer Sciense PDF, IUPAC recommedndations 1996, prepared by a working group consisting of: A.D. Jenkins, P. Kratochvil, R.F.T. Stepto and U.W. Suter