Biopolymers have a myriad of applications which may be considered as novel not only
in agriculture and agribusiness, consumer science, sports, transparent and optical materials and in
biological and medical materials but also in controlled drug delivery and targeting. This chapter
will highlight the major applications of biopolymers as enunciated in the preceding sentence with
special emphasis on the use of engineered polymers and polymeric systems in controlled drug
delivery and targeting. Successful pharmacotherapy intervention requires strict control over the
spatial and temporal characteristics of drug delivery. Engineered polymers are the materials used
today to construct carriers with controlled drug delivery properties, that is, carriers which could
perform one or more of the following: (a) increase drug availability to the target cells, (b) increase
selectivity towards the target cells, (c) release their drug load only at the site of drug action (or
nearby) in response to internal or external stimuli (e.g. pH or temperature changes) and (d) release
drug only when it is required in response to biological signals (e.g. an increase in glucose levels in
blood). The development of such polymers has caused advances in polymer chemistry, which, in
turn, has resulted in smart polymers that can respond to changes in environmental conditions. The
responses vary widely from swelling/deswelling to degradation. Drug-polymer conjugates and
drug-containing nano/micro-particles have been used for drug targeting. Engineered polymers and
polymeric systems have been used in new areas, such as molecular imaging as well as in more
recent applications in nanotechnology.
