PLGA

{{other uses}}

{{other uses}}

[[Image:PLGA.svg|thumb|Structure of poly(lactic-''co''-glycolic acid). ''x''= number of units of [[lactic acid]]; ''y''= number of units of [[glycolic acid]].]]

[[Image:PLGA.svg|thumb|Structure of poly(lactic-''co''-glycolic acid). ''x''= number of units of [[lactic acid]]; ''y''= number of units of [[glycolic acid]].]]

'''PLGA''', '''PLG''', or '''poly(lactic-''co''-glycolic) acid''' ([[CAS Registry Number|CAS]]: {{CAS|26780-50-7}}) is a [[copolymer]] which is used in a host of [[Food and Drug Administration]] (FDA) approved therapeutic devices, owing to its [[biodegradation|biodegradability]] and [[biocompatibility]].{{cite journal | vauthors = Abulateefeh SR | title = Long-acting injectable PLGA/PLA depots for leuprolide acetate: successful translation from bench to clinic | journal = Drug Delivery and Translational Research | volume = 13 | issue = 2 | pages = 520–530 | date = February 2023 | pmid = 35976565 | doi = 10.1007/s13346-022-01228-0 | s2cid = 251622670 }} PLGA is synthesized by means of ring-opening co-polymerization of two different [[monomer]]s: [[glycolide]] and [[lactide]], the cyclic dimers (1,4-dioxane-2,5-diones) of [[glycolic acid]] and [[lactic acid]], respectively. Polymers can be synthesized as either random or block copolymers thereby imparting additional polymer properties. Common catalysts used in the preparation of this polymer include [[tin(II) 2-ethylhexanoate]], tin(II) [[alkoxide]]s, or [[aluminum isopropoxide]]. During polymerization, successive monomeric units of glycolic or lactic acid are linked together in PLGA by [[ester]] linkages, thus yielding a linear, [[polyester]] as a product.{{cite journal | vauthors = Astete CE, Sabliov CM | title = Synthesis and characterization of PLGA nanoparticles | journal = Journal of Biomaterials Science. Polymer Edition | volume = 17 | issue = 3 | pages = 247–289 | year = 2006 | pmid = 16689015 | doi = 10.1163/156856206775997322 | s2cid = 7607080 }} PLGA has also emerged as platform for advanced drug delivery systems, including nanoparticles, because of its tunable degradation behavior and ability to encapsulate different therapeutic agents.{{Cite journal |last1=Stevanović |first1=Magdalena M. |last2=Qian |first2=Kun |last3=Huang |first3=Lin |last4=Vukomanović |first4=Marija |date=2025-12-15 |title=PLGA-Based Co-Delivery Nanoformulations: Overview, Strategies, and Recent Advances |journal=Pharmaceutics |volume=17 |issue=12 |page=1613 |doi=10.3390/pharmaceutics17121613 |doi-access=free|issn=1999-4923 |pmc=12736669 |pmid=41471127}} Recent research features its growing role in precision medicine and targeted therapies, specifically in cancer treatment and controlled release applications.{{Cite journal |last1=Uzakova |first1=Assem B. |last2=Yergaliyeva |first2=Elmira M. |last3=Yerlanuly |first3=Azamat |last4=Mukatayeva |first4=Zhazira S. |date=2025-12-22 |title=A Systematic Review of Advanced Drug Delivery Systems: Engineering Strategies, Barrier Penetration, and Clinical Progress (2016-April 2025) |journal=Pharmaceutics |volume=18 |issue=1 |page=11 |doi=10.3390/pharmaceutics18010011 |doi-access=free|issn=1999-4923 |pmc=12845006 |pmid=41599119}}

'''PLGA''', '''PLG''', or '''poly(lactic-''co''-glycolic) acid''' ([[CAS Registry Number|CAS]]: {{CAS|26780-50-7}}) is a biodegradable, biocompatible [[Copolymer|copolyme]]r of lactic and glycolic acid used widely in biomedical devices and tissue-engineering materials approved by the [[Food and Drug Administration]] (FDA).{{cite journal | vauthors = Abulateefeh SR | title = Long-acting injectable PLGA/PLA depots for leuprolide acetate: successful translation from bench to clinic | journal = Drug Delivery and Translational Research | volume = 13 | issue = 2 | pages = 520–530 | date = February 2023 | pmid = 35976565 | doi = 10.1007/s13346-022-01228-0 | s2cid = 251622670 }} PLGA has also emerged as platform for advanced drug delivery systems, including nanoparticles, because of its tunable degradation behavior and ability to encapsulate different therapeutic agents.{{Cite journal |last1=Stevanović |first1=Magdalena M. |last2=Qian |first2=Kun |last3=Huang |first3=Lin |last4=Vukomanović |first4=Marija |date=2025-12-15 |title=PLGA-Based Co-Delivery Nanoformulations: Overview, Strategies, and Recent Advances |journal=Pharmaceutics |volume=17 |issue=12 |page=1613 |doi=10.3390/pharmaceutics17121613 |doi-access=free|issn=1999-4923 |pmc=12736669 |pmid=41471127}} Recent research features its growing role in precision medicine and targeted therapies, specifically in cancer treatment and controlled release applications.{{Cite journal |last1=Uzakova |first1=Assem B. |last2=Yergaliyeva |first2=Elmira M. |last3=Yerlanuly |first3=Azamat |last4=Mukatayeva |first4=Zhazira S. |date=2025-12-22 |title=A Systematic Review of Advanced Drug Delivery Systems: Engineering Strategies, Barrier Penetration, and Clinical Progress (2016-April 2025) |journal=Pharmaceutics |volume=18 |issue=1 |page=11 |doi=10.3390/pharmaceutics18010011 |doi-access=free|issn=1999-4923 |pmc=12845006 |pmid=41599119}} PLGA is synthesized by means of ring-opening co-polymerization of two different [[monomer]]s: [[glycolide]] and [[lactide]], the cyclic dimers (1,4-dioxane-2,5-diones) of [[glycolic acid]] and [[lactic acid]], respectively.{{Cite journal |last=Dechy-Cabaret |first=Odile |last2=Martin-Vaca |first2=Blanca |last3=Bourissou |first3=Didier |date=2004-12-01 |title=Controlled Ring-Opening Polymerization of Lactide and Glycolide |url=https://pubs.acs.org/doi/10.1021/cr040002s |journal=Chemical Reviews |language=en |volume=104 |issue=12 |pages=6147–6176 |doi=10.1021/cr040002s |issn=0009-2665}}

==Copolymer==

== Synthesis ==

PLGA is typically synthesized by ring-opening polymerization of the cyclic dimers lactide and glycolide, a method widely used because it allows better control over molecular weight and copolymer composition than direct condensation methods. Other reports show direct [[polycondensation]] of lactic acid and glycolic acid as another method, but this approach gives lower molecular weight material and is less suitable for producing controlled, high-performance PLGA grades. Common catalysts include [[tin(II) 2-ethylhexanoate]] and related organometallic catalysts, which are widely used in melt polymerization because of their activity and practical availability.{{cite journal | vauthors = Astete CE, Sabliov CM | title = Synthesis and characterization of PLGA nanoparticles | journal = Journal of Biomaterials Science. Polymer Edition | volume = 17 | issue = 3 | pages = 247–289 | year = 2006 | pmid = 16689015 | doi = 10.1163/156856206775997322 | s2cid = 7607080 }}{{Cite journal |last=Hua |first=Yabing |last2=Su |first2=Yuhuai |last3=Zhang |first3=Hui |last4=Liu |first4=Nan |last5=Wang |first5=Zengming |last6=Gao |first6=Xiang |last7=Gao |first7=Jing |last8=Zheng |first8=Aiping |date=2021-01 |title=Poly(lactic-co-glycolic acid) microsphere production based on quality by design: a review |url=https://www.tandfonline.com/doi/full/10.1080/10717544.2021.1943056 |journal=Drug Delivery |language=en |volume=28 |issue=1 |pages=1342–1355 |doi=10.1080/10717544.2021.1943056 |issn=1071-7544 |pmc=8245074 |pmid=34180769}}

Depending on the ratio of lactide to glycolide used for the polymerization, different forms of PLGA can be obtained: these are usually identified in regard to the molar ratio of the monomers used (e.g. PLGA 75:25 identifies a copolymer whose composition is 75% lactic acid and 25% glycolic acid). The crystallinity of PLGAs will vary from fully [[Amorphous solid|amorphous]] to fully [[crystallinity|crystalline]] depending on block structure and molar ratio. PLGAs typically show a [[glass transition temperature]] in the range of 40-60 °C. PLGA can be dissolved by a wide range of [[solvent]]s, depending on composition. Higher lactide polymers can be dissolved using [[chlorine|chlorinated]] solvents whereas higher glycolide materials will require the use of fluorinated solvents such as [[Hexafluoro-2-propanol|HFIP]].

== Copolymer ==

Depending on the ratio of lactide to glycolide used for the polymerization, different forms of PLGA can be obtained: these are usually identified in regard to the molar ratio of the monomers used (e.g. PLGA 75:25 identifies a copolymer whose composition is 75% lactic acid and 25% glycolic acid). The crystallinity of PLGAs will vary from fully [[Amorphous solid|amorphous]] to fully [[crystallinity|crystalline]] depending on block structure and molar ratio. PLGA typically show a [[glass transition temperature]] in the range of 40-60 °C. PLGA can be dissolved by a wide range of [[solvent]]s, depending on composition. Higher lactide polymers can be dissolved using [[chlorine|chlorinated]] solvents whereas higher glycolide materials will require the use of fluorinated solvents such as [[Hexafluoro-2-propanol|HFIP]].

PLGA degrades by [[hydrolysis]] of its ester linkages in the presence of [[water (molecule)|water]]. It has been shown that the time required for degradation of PLGA is related to the monomers' ratio used in production: the higher the content of glycolide units, the lower the time required for degradation as compared to predominantly lactide materials. An exception to this rule is the copolymer with 50:50 monomers' ratio which exhibits the faster degradation (about two months). In addition, polymers that are end-capped with esters (as opposed to the free [[carboxylic acid]]) demonstrate longer degradation half-lives.{{cite journal | vauthors = Samadi N, Abbadessa A, Di Stefano A, van Nostrum CF, Vermonden T, Rahimian S, Teunissen EA, van Steenbergen MJ, Amidi M, Hennink WE | display-authors = 6 | title = The effect of lauryl capping group on protein release and degradation of poly(D,L-lactic-co-glycolic acid) particles | journal = Journal of Controlled Release | volume = 172 | issue = 2 | pages = 436–443 | date = December 2013 | pmid = 23751568 | doi = 10.1016/j.jconrel.2013.05.034 | hdl = 1874/465771 }} This flexibility in degradation has made it convenient for fabrication of many [[medical device]]s, such as, [[grafts]], [[Surgical suture|sutures]], [[implant (medicine)|implants]], [[prosthetic devices]], surgical sealant films, micro and [[nanoparticles]].{{cite journal | vauthors = Pavot V, Berthet M, Rességuier J, Legaz S, Handké N, Gilbert SC, Paul S, Verrier B | display-authors = 6 | title = Poly(lactic acid) and poly(lactic-co-glycolic acid) particles as versatile carrier platforms for vaccine delivery | journal = Nanomedicine | volume = 9 | issue = 17 | pages = 2703–2718 | date = December 2014 | pmid = 25529572 | doi = 10.2217/nnm.14.156 }}

PLGA degrades by [[hydrolysis]] of its ester linkages in the presence of [[water (molecule)|water]]. It has been shown that the time required for degradation of PLGA is related to the monomers' ratio used in production: the higher the content of glycolide units, the lower the time required for degradation as compared to predominantly lactide materials. An exception to this rule is the copolymer with 50:50 monomers' ratio which exhibits the faster degradation (about two months). In addition, polymers that are end-capped with esters (as opposed to the free [[carboxylic acid]]) demonstrate longer degradation half-lives.{{cite journal | vauthors = Samadi N, Abbadessa A, Di Stefano A, van Nostrum CF, Vermonden T, Rahimian S, Teunissen EA, van Steenbergen MJ, Amidi M, Hennink WE | display-authors = 6 | title = The effect of lauryl capping group on protein release and degradation of poly(D,L-lactic-co-glycolic acid) particles | journal = Journal of Controlled Release | volume = 172 | issue = 2 | pages = 436–443 | date = December 2013 | pmid = 23751568 | doi = 10.1016/j.jconrel.2013.05.034 | hdl = 1874/465771 }} This flexibility in degradation has made it convenient for fabrication of many [[medical device]]s, such as, [[grafts]], [[Surgical suture|sutures]], [[implant (medicine)|implants]], [[prosthetic devices]], surgical sealant films, micro and [[nanoparticles]].{{cite journal | vauthors = Pavot V, Berthet M, Rességuier J, Legaz S, Handké N, Gilbert SC, Paul S, Verrier B | display-authors = 6 | title = Poly(lactic acid) and poly(lactic-co-glycolic acid) particles as versatile carrier platforms for vaccine delivery | journal = Nanomedicine | volume = 9 | issue = 17 | pages = 2703–2718 | date = December 2014 | pmid = 25529572 | doi = 10.2217/nnm.14.156 }}

The biodegradation of PLGA makes it useful for plenty of medical applications with PLGA undergoing bulk degradation primarily.{{Cite book | vauthors = Wnek GE, Bowlin GL |url=https://books.google.com/books?id=0ThZDwAAQBAJ&pg=PP1 |title=Encyclopedia of Biomaterials and Biomedical Engineering |date=2008-05-28 |publisher=CRC Press |isbn=978-1-4987-6143-7 |language=en}} For example, a 75:25 lactide to glycolide PLGA ratio can be made as microspheres that degrade via bulk erosion, with polymer composition playing a role in the degradation behavior. This would allow degradation throughout the whole polymer to occur equally.{{Cite journal |last1=Siepmann |first1=J. |last2=Siepmann |first2=F. |date=December 2025 |title=Release mechanisms of PLGA-based drug delivery systems: A review |journal=International Journal of Pharmaceutics: X |language=en |volume=10 |article-number=100440 |doi=10.1016/j.ijpx.2025.100440 |pmc=12663523 |pmid=41323846}}

The biodegradation of PLGA makes it useful for plenty of medical applications with PLGA undergoing bulk degradation primarily.{{Cite book | vauthors = Wnek GE, Bowlin GL |url=https://books.google.com/books?id=0ThZDwAAQBAJ&pg=PP1 |title=Encyclopedia of Biomaterials and Biomedical Engineering |date=2008-05-28 |publisher=CRC Press |isbn=978-1-4987-6143-7 |language=en}} For example, a 75:25 lactide to glycolide PLGA ratio can be made as microspheres that degrade via bulk erosion, with polymer composition playing a role in the degradation behavior. This would allow degradation throughout the whole polymer to occur equally.{{Cite journal |last1=Siepmann |first1=J. |last2=Siepmann |first2=F. |date=December 2025 |title=Release mechanisms of PLGA-based drug delivery systems: A review |journal=International Journal of Pharmaceutics: X |language=en |volume=10 |article-number=100440 |doi=10.1016/j.ijpx.2025.100440 |pmc=12663523 |pmid=41323846}}

PLGA is also widely used in injectable forms developed to have eroding systems. This form can be used in [[Leuprorelin|Lupron Depot]]. To achieve this, PLGA is dissolved with an organic water-miscible solvent approved by the [[Food and Drug Administration]] (FDA) to create a homogeneous solution or suspension. When injected, the solvent diffuses into the surrounding aqueous environment, causing PLGA to precipitate and form a solid depot. The encapsulated drug is released as the polymer gradually degrades. However, a problem that may occur during the initial injection is that the drug may be released in a quick burst instead of gradually.

PLGA is also widely used in injectable forms developed to have eroding systems. This form can be used in [[Leuprorelin|Lupron Depot]]. To achieve this, PLGA is dissolved with an organic water-miscible solvent approved by the FDA to create a homogeneous solution or suspension. When injected, the solvent diffuses into the surrounding aqueous environment, causing PLGA to precipitate and form a solid depot. The encapsulated drug is released as the polymer gradually degrades. However, a problem that may occur during the initial injection is that the drug may be released in a quick burst instead of gradually.

==Clinical and Research Applications==

==Clinical and Research Applications==