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'''Đại phân tử''' là loại [[phân tử]] rất lớn thường được tạo ra bởi [[phản ứng trùng hợp]] của các đơn vị nhỏ hơn ([[monomer]]). Các đại phân tử điển hình thường chứa hàng nghìn đến hàng chục nghìn [[nguyên tử]]. Đại phân tử hay gặp trong [[hóa sinh]] đó là [[polime sinh học]] (biopolymers) ([[axit nucleic]], [[protein]], [[cacbohydrat]] và [[polyphenol]]) và các phân tử phi polime lớn (như là [[lipid]] và [[macrocycle]]).<ref name="Stryer_2002">{{chú thích sách |author= Stryer L, Berg JM, Tymoczko JL | title = Biochemistry | publisher = W.H. Freeman | location = San Francisco | year = 2002 | edition = 5th | isbn = 0-7167-4955-6 | url = http://www.ncbi.nlm.nih.gov/books/NBK21154/ }}</ref> Các đại phân tử tổng hợp thường thấy bao gồm [[chất dẻo]] và [[sợi tổng hợp]] cũng như các vật liệu trong phòng thí nghiệm như [[ống nano cacbon]].<ref>[http://www.americanchemistry.com/s_plastics/doc.asp?CID=1571&DID=5972 Life cycle of a plastic product]. Americanchemistry.com. Truy cập 2011-07-01.</ref><ref>{{cite journal |last1=Gullapalli |first1=S. |last2=Wong |first2=M.S. |year=2011 |title=Nanotechnology: A Guide to Nano-Objects |url=http://www.aiche.org/uploadedFiles/Publications/CEPMagazine/051128_public.pdf |journal=Chemical Engineering Progress |volume=107 |issue=5 |pages=28–32}}</ref>
==Định nghĩa==
{{Quote box
|title = IUPAC definition
|quote = '''Macromolecule'''<br/>'''Polymer molecule'''
A molecule of high relative molecular mass, the structure of which essentially<br/>comprises the multiple repetition of units derived, actually or conceptually, from<br/>molecules of low relative molecular mass.
;Notes
1. In many cases, especially for synthetic polymers, a molecule can be regarded<br/>as having a high relative molecular mass if the addition or removal of one or a<br/>few of the units has a negligible effect on the molecular properties. This statement<br/>fails in the case of certain macromolecules for which the properties may be<br/>critically dependent on fine details of the molecular structure.<br/>
2. If a part or the whole of the molecule fits into this definition, it may be described<br/>as either ''macromolecular'' or ''polymeric'', or by ''polymer'' used adjectivally.<ref>{{cite journal|title=Glossary of basic terms in polymer science (IUPAC Recommendations 1996)|journal=[[Pure and Applied Chemistry]]|date=1996|volume=68|issue=12|pages=2287–2311|doi=10.1351/pac199668122287|url=http://pac.iupac.org/publications/pac/pdf/1996/pdf/6812x2287.pdf}}</ref>
}}
The term ''macromolecule'' (''[[wikt:macro-#Prefix|macro-]]'' + ''molecule'') was coined by [[Nobel Prize|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).<ref>{{cite journal|author=Staudinger, H.; Fritschi, J. |title=Über Isopren und Kautschuk. 5. Mitteilung. Über die Hydrierung des Kautschuks und über seine Konstitution|doi=10.1002/hlca.19220050517|date=1922|journal=Helvetica Chimica Acta|volume=5|issue=5|pages=785}}</ref> At that time the phrase ''polymer'', as introduced by [[Jöns Jakob Berzelius|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.<ref name=Jensen>{{cite journal|doi=10.1021/ed085p624|title=The Origin of the Polymer Concept|date=2008|last1=Jensen|first1=William B.|journal=Journal of Chemical Education|volume=85|pages=624|issue=5|bibcode = 2008JChEd..85..624J }}</ref>
Usage of the term to describe large molecules varies among the disciplines. For example, while [[biology]] refers to macromolecules as the four large molecules comprising living things, in [[chemistry]], the term may refer to aggregates of two or more molecules held together by [[intermolecular force]]s rather than [[covalent bond]]s but which do not readily dissociate.<ref>van Holde, K.E. (1998) ''Principles of Physical Biochemistry'' Prentice Hall: New Jersey, ISBN 0-13-720459-0</ref>
According to the standard [[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 [[Chemical substance|substance]] composed of macromolecules.<ref>{{cite journal|url=http://www.iupac.org/reports/1996/6812jenkins/6812basicterms.pdf|journal=Pure and Applied Chemistry |volume=68|page=2287|date=1996|author=Jenkins, A. D.|title=Glossary of Basic Terms in Polymer Science|doi=10.1351/pac199668122287|last2=Kratochvíl|first2=P.|last3=Stepto|first3=R. F. T.|last4=Suter|first4=U. W.|issue=12}}</ref>
Because of their size, macromolecules are not conveniently described in terms of [[stoichiometry]] alone. The structure of simple macromolecules, such as homopolymers, may be described in terms of the individual monomer subunit and total [[molecular mass]]. Complicated biomacromolecules, on the other hand, require multi-faceted structural description such as the hierarchy of structures used to describe [[proteins]]. In [[British English]], the word "macromolecule" tends to be called "'''high polymer'''".<ref>[http://www.highpolymer.org.uk/ High Polymer Research Group]</ref>
== Tham khảo ==
{{tham khảo|35em}}
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