PLGA

PLGA, PLG, or poly(lactic-co-glycolic) acid (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 biodegradability and biocompatibility.

During polymerization, successive monomeric units (of glycolic or lactic acid) are linked together in PLGA by ester linkages, thus yielding a linear, aliphatic polyester as a product.

[2] 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).

In addition, polymers that are end-capped with esters (as opposed to the free carboxylic acid) demonstrate longer degradation half-lives.

[5] The body also can metabolize the two monomers, which in the case of glycolic acid produces small amounts of the toxic oxalic acid, though the amounts produced from typical applications are minuscule and there is minimal systemic toxicity associated with using PLGA for biomaterial applications.

However, it has been reported that the acidic degradation of PLGA reduces the local pH low enough to create an autocatalytic environment.

Its high biocompatibility results from its composition due to lactic and glycolic acid fermentation from sugars, making them eco-friendly and less reactive in the body.

For example, in drug delivery systems (DDS), PLGA and PLA implants with high surface area and low volume of injection can increase one's chance of immune response as the polymers degrade in the body.

To achieve this, PLGA is mixed with an organic water-miscible solvent approved by the Food and Drug Administration (FDA).