15
Many bibliographic reports have suggested that PLGA-based carriers improve
bioavailability and reduce the side effects of paclitaxel and its derivatives (Mandal
et al. 2018; Peng et al. 2018). In addition, a PLGA/PEG polymer encapsulated a
perfluoroopentane perfluorocarbon (PFP) variable phase, thus significantly improving the image signal after induction of low-intensity focused ultrasound (LIFU) to
improve the accuracy of clinical detection of thyroid nodules (Hu et al. 2018).
PLGA-based nanosystems also have potential for sustained intracranial delivery of
therapeutic agents to treat brain tumors (Cano et al. 2018; Sánchez-López et al.
2018; Silva-Abreu et al. 2018). In general, PLGA-based nanosystems are beneficial
for micromolecular drug delivery, resulting in better bioavailability of the drug and
reduced side effects.
2.4.2 PLGA-Based Nanosystems for the Transfer
of Biomacromolecules
It is well known that peptides, proteins and enzymes have large and complex structures with low capacity to cross biological barriers. These macromolecules tend to
be easily degraded. The incorporation of compounds into PLGA-based composite
polymer nanoparticles seems to be a promising strategy to overcome the problems
mentioned above. For example, Chen et al. (2018a, b) used bovine serum albumin
and lecithin to obtain PLGA-coated nanocomposites to be a promising platform for
long-term protein delivery with a reduced initial burst. Wei et al. (2018) found that
nanoporous PLGA-based microspheres loaded with soy lecithin showed a controlled release of the protein. Shi et al. (2018) also developed PLGA-based nanosystems for prolonged glucoregulatory action of exenatide (peptide) to be used for type
2 diabetes therapy. Therefore, PLGA delivery systems can be potential delivery
systems for peptides, proteins and enzymes.
2.5 Conclusions and Perspectives
Biodegradable and biocompatible synthetic polymers have allowed the development of nanomedical compounds and theranostics devices. These compounds have
proven to be promising carries for the delivery and release of bioactive compounds
on diseased tissues. There are two mechanisms for the delivery of bioactive compounds over the target region: (1) drugs containing reactive functional groups such
as hydroxyl, carboxyl and amino groups can be conjugated directly to the polymer
adopting a suitable synthetic strategy and (2) the polymers can be assembled in
nano-sized particles (spheres and micelles) via hydrogen bonds, hydrophobic interaction, electrostatic bonding and multiple intermolecular interactions to load the
bioactive compounds. Despite the advantages offered by synthetic polymers, only a
2 Biodegradable and Functional Synthetic Polymers in Nanomedicine: Controlled…
Many bibliographic reports have suggested that PLGA-based carriers improve
bioavailability and reduce the side effects of paclitaxel and its derivatives (Mandal
et al. 2018; Peng et al. 2018). In addition, a PLGA/PEG polymer encapsulated a
perfluoroopentane perfluorocarbon (PFP) variable phase, thus significantly improving the image signal after induction of low-intensity focused ultrasound (LIFU) to
improve the accuracy of clinical detection of thyroid nodules (Hu et al. 2018).
PLGA-based nanosystems also have potential for sustained intracranial delivery of
therapeutic agents to treat brain tumors (Cano et al. 2018; Sánchez-López et al.
2018; Silva-Abreu et al. 2018). In general, PLGA-based nanosystems are beneficial
for micromolecular drug delivery, resulting in better bioavailability of the drug and
reduced side effects.
2.4.2 PLGA-Based Nanosystems for the Transfer
of Biomacromolecules
It is well known that peptides, proteins and enzymes have large and complex structures with low capacity to cross biological barriers. These macromolecules tend to
be easily degraded. The incorporation of compounds into PLGA-based composite
polymer nanoparticles seems to be a promising strategy to overcome the problems
mentioned above. For example, Chen et al. (2018a, b) used bovine serum albumin
and lecithin to obtain PLGA-coated nanocomposites to be a promising platform for
long-term protein delivery with a reduced initial burst. Wei et al. (2018) found that
nanoporous PLGA-based microspheres loaded with soy lecithin showed a controlled release of the protein. Shi et al. (2018) also developed PLGA-based nanosystems for prolonged glucoregulatory action of exenatide (peptide) to be used for type
2 diabetes therapy. Therefore, PLGA delivery systems can be potential delivery
systems for peptides, proteins and enzymes.
2.5 Conclusions and Perspectives
Biodegradable and biocompatible synthetic polymers have allowed the development of nanomedical compounds and theranostics devices. These compounds have
proven to be promising carries for the delivery and release of bioactive compounds
on diseased tissues. There are two mechanisms for the delivery of bioactive compounds over the target region: (1) drugs containing reactive functional groups such
as hydroxyl, carboxyl and amino groups can be conjugated directly to the polymer
adopting a suitable synthetic strategy and (2) the polymers can be assembled in
nano-sized particles (spheres and micelles) via hydrogen bonds, hydrophobic interaction, electrostatic bonding and multiple intermolecular interactions to load the
bioactive compounds. Despite the advantages offered by synthetic polymers, only a
2 Biodegradable and Functional Synthetic Polymers in Nanomedicine: Controlled…