A novel method of studying polymer biodegradation

Abstract

A novel combination of laser light scattering (LLS) and the micronization of a water-insoluble polymer into narrowly distributed nanoparticles stable in water has provided not only an accurate, reliable and microscopic method to study polymer biodegradation, but also a novel and fast way to evaluate the biodegradability of a given polymer. Using poly(ε-caprolactone) (PCL) as a typical example, we have shown that its biodegradation time can be shortened by a factor of more than 10 3 times in comparison with the time required to biodegrade a thin film (10 × 10 × 0.1 mm 3). Moreover, the biodegradation kinetics can be in-situ monitored in terms of the decrease of the time-average scattering intensity and the particle number. A comparison of static and dynamic LLS results revealed that the enzyme, Lipase Pseudomonas, “eats” the PCL nanoparticles in an one-by-one manner and the enzymatic biodegradation of PCL follows a zero-order kinetics.