PHYS01200704032 Debes Ray - Homi Bhabha National Institute

Chapter 2: Block Copolymer-mediated Synthesis of Gold Nanoparticles
2.2.3. Applications of Block Copolymers
The potential applications of amphiphilic block copolymers include solubilization,
stabilization, drug delivery, nanostructure synthesis, growth template for mesoporous
inorganic materials etc [111,113,115,129]. Some of these applications are summarized below:
(i) Solubilization: There have been numerous studies on the use of amphiphilic block
copolymers to solubilize molecules, in particular the use of water soluble block copolymers
to solubilize organic compounds (oils) which are immiscible in water. In fact, industrial
applications of block copolymers, such as agrochemical dispersions or pharmaceutical
formulations, rely on this solubilization capacity [129].
(ii) Emulsification and Stabilization: Amphiphilic block copolymers are widely used to
stabilize emulsions and microemulsions. Due to their interfacial activity, they segregate to the
oil-water interface, reducing the interfacial tension to facilitate mixing. The interfacial
tension is reduced dramatically upon addition of the block copolymer and the microemulsion
can swell to a greater extent [130].
(iii) Drug delivery: Mainly PEO-based block copolymers have been used for targeted
delivery. They are utilized for improved drug delivery in efficient patient-acceptable
formulations, for coatings to reduce protein adhesion or clotting and for structural gels and
wound coverings etc [131]. Applications of block copolymer gelation in the development of
thermally controlled delivery systems for slow drug release (e.g. biodegradable hydrogels or
thermo-responsive block copolymers) have also been explored in a great extent [132].
(iv) Templating: Block copolymers have been extensively used to template the formation of
mesoporous materials [133]. Compared with the conventional non-ionic surfactants,
amphiphilic block copolymers offer the advantage of having larger pore sizes. Since the pore
size and wall thickness can be varied according to the processing conditions, copolymers act
as structure directing agents [133,134]. For example, production of mesoporous silica in thin
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