A novel combination of laser light scattering (LLS) and the micronizat
ion of a water-insoluble polymer into narrowly distributed nanoparticl
es stable in water has provided not only an accurate, reliable and mic
roscopic method to study polymer biodegradation, but also a novel and
fast way to evaluate the biodegradability of a given polymer. Using po
ly(epsilon-caprolactone) (PCL) as a typical example, we have shown tha
t 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 fi
lm (10 x 10 x 0.1 mm(3)). Moreover, the biodegradation kinetics can be
in-situ monitored in terms of the decrease of the time-average scatte
ring intensity and the particle number. A comparison of static and dyn
amic LLS results revealed that the enzyme, Lipase Pseudomonas, ''eats'
' the PCL nanoparticles in an one-by-one manner and the enzymatic biod
egradation of PCL follows a zero-order kinetics. (C) 1998 Elsevier Sci
ence Ltd. All rights reserved.