Poly(lactic-co-glycolic acid) (PLGA) is made from two monomers, lactic acid and glycolic acid. The ratio of the monomers and the molecular weight set the identity and properties. For example, PLGA 88:12 means the polymer is made of 88 percent lactic acid and 12 percent glycolic acid. Generally, the higher the percentage of lactide units, the longer the polymer lasts before degrading in the presence of water. The higher the molecular weight, the greater the mechanical strength.