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composite nanoparticle. Mrówczyński et al. (2018) developed polydopaminecoated magnetic nanoparticles of doxorubicin combined with mono-6-thio-βcyclodextrin for cancer therapy. The hepatic cancer cellular uptake of
doxorubicin-loaded nanoparticles was investigated by confocal imaging microscopy, and the significant anticancer effect of magnetic nanoparticles was observed.
7.5 Role of Cyclodextrin in Polymeric Nanoparticles
Polymeric nanoparticles are both biocompatible and biodegradable, so the fate of
the nanoparticles in biological system is not a concern. Examples of natural and
synthetic polymers used in the nanoparticles are chitosan, polyethylene glycol, poly
(lactic acid), and poly (lactic-co-glycolic acid) poly(cyanoacrylates). The inclusion
property of cyclodextrin renders polymeric nanoparticles to conveniently deliver
hydrophobic molecules to the targeted site by encapsulating the drugs in the hydrophobic cyclodextrin cavity. The polymeric nanoparticles have cyclodextrin casting
outer shells, while the core of the polymeric nanoparticles is composed of natural or
synthetic polymer. Thus, the drugs can be loaded in the core of the polymeric
nanoparticles, or it can be conjugated with the cyclodextrin in the outer shell.
Nanoparticulate systems can be prepared either by dispersion of preformed polymers or polymerization. Among the polymers used in the nanoparticle preparation
is poly(cyanoacrylates) which are particularly interesting, because of their biodegradability and very simple polymerization process. One of the major drawbacks of
this type of nanoparticle is related to the difficulty of entrapping in hydrophobic drugs.
Da Silveira et al. (1998) first proposed cyclodextrin to overcome this problem.
The authors proposed possibility of preparing nanoparticles of poly(isobutyl cyanoacrylate) in the presence of hydroxypropyl-β-cyclodextrin by anionic polymerization of isobutyl cyanoacrylate. Later, Ren et al. (2009) dissolved
adamantane-end-capped poly(ε-caprolactone) and poly(vinylpyrrolidone)-cyclodextrin in N-methyl-2-pyrrolidone, a common solvent for both polymers. Further
addition of this mixed polymer solution in solvent results in self-assembled polymeric nanoparticles. The same year, Zhang and Ma (2009) reported synthesis of
polymeric core-shell assemblies based on inclusion complexes of a wide variety of
poorly soluble drugs such as indomethacin and coumarin as guest molecules with a
polyaspartamide copolymer composed of a block carrying cyclodextrin units and a
polyethylene glycol block (polyethylene glycol-β-cyclodextrin). Subsequently
incubation of these assemblies in buffer medium provides a prolong release of these
compounds. The chronological summary of various major cyclodextrin-based polymeric nanoparticles is illustrated in Table 7.1.
A. Pandey
composite nanoparticle. Mrówczyński et al. (2018) developed polydopaminecoated magnetic nanoparticles of doxorubicin combined with mono-6-thio-βcyclodextrin for cancer therapy. The hepatic cancer cellular uptake of
doxorubicin-loaded nanoparticles was investigated by confocal imaging microscopy, and the significant anticancer effect of magnetic nanoparticles was observed.
7.5 Role of Cyclodextrin in Polymeric Nanoparticles
Polymeric nanoparticles are both biocompatible and biodegradable, so the fate of
the nanoparticles in biological system is not a concern. Examples of natural and
synthetic polymers used in the nanoparticles are chitosan, polyethylene glycol, poly
(lactic acid), and poly (lactic-co-glycolic acid) poly(cyanoacrylates). The inclusion
property of cyclodextrin renders polymeric nanoparticles to conveniently deliver
hydrophobic molecules to the targeted site by encapsulating the drugs in the hydrophobic cyclodextrin cavity. The polymeric nanoparticles have cyclodextrin casting
outer shells, while the core of the polymeric nanoparticles is composed of natural or
synthetic polymer. Thus, the drugs can be loaded in the core of the polymeric
nanoparticles, or it can be conjugated with the cyclodextrin in the outer shell.
Nanoparticulate systems can be prepared either by dispersion of preformed polymers or polymerization. Among the polymers used in the nanoparticle preparation
is poly(cyanoacrylates) which are particularly interesting, because of their biodegradability and very simple polymerization process. One of the major drawbacks of
this type of nanoparticle is related to the difficulty of entrapping in hydrophobic drugs.
Da Silveira et al. (1998) first proposed cyclodextrin to overcome this problem.
The authors proposed possibility of preparing nanoparticles of poly(isobutyl cyanoacrylate) in the presence of hydroxypropyl-β-cyclodextrin by anionic polymerization of isobutyl cyanoacrylate. Later, Ren et al. (2009) dissolved
adamantane-end-capped poly(ε-caprolactone) and poly(vinylpyrrolidone)-cyclodextrin in N-methyl-2-pyrrolidone, a common solvent for both polymers. Further
addition of this mixed polymer solution in solvent results in self-assembled polymeric nanoparticles. The same year, Zhang and Ma (2009) reported synthesis of
polymeric core-shell assemblies based on inclusion complexes of a wide variety of
poorly soluble drugs such as indomethacin and coumarin as guest molecules with a
polyaspartamide copolymer composed of a block carrying cyclodextrin units and a
polyethylene glycol block (polyethylene glycol-β-cyclodextrin). Subsequently
incubation of these assemblies in buffer medium provides a prolong release of these
compounds. The chronological summary of various major cyclodextrin-based polymeric nanoparticles is illustrated in Table 7.1.
A. Pandey