PLGA is commonly used in medical applications because it is biocompatible and biodegradable. The main mechanism through which PLGA (structure shown below) biodegrades is hydrolysis. During hydrolysis, penetration of water molecules causes ester bonds in the copolymer to be cleaved, leaving the newly formed end groups to bond with hydroxyl groups and hydrogen atoms within the water molecules. This causes the polymer chain to separate. Over time, the process of hydrolysis results in complete degradation of PLGA.
Several additional factors can influence the rate at which PLGA degrades. For example, exposing the polymer to an alkaline or strongly acidic medium can accelerate degradation. Other factors that may increase the degradation rate include exposure to certain enzymes, addition of hydrophilic surface treatments, a decrease in or a low initial molecular weight, a low degree of crystallinity, and a high volume to surface area ratio.
It is important to consider all environmental factors in order to control the degradation rate of PLGA. This is particularly important for drug delivery, as degradation of the polymer directly affects the release profile of the drug. The technical support department at Phosphorex is happy to work with you to create customized PLGA microspheres or nanoparticles to suit your particular application.