Types of nanocarriers for drug delivery
| System . | Structure . | Characteristics . | Examples of compounds . | Ref. . |
|---|---|---|---|---|
| Polymeric nanoparticles (polymer-drug conjugates) | Drugs are conjugated to the side chain of a linear polymer with a linker (cleavable bond) | (a) Water-soluble, nontoxic, biodegradable | Albumin-Taxol (Abraxane) | (7) |
| (b) Surface modification (pegylation) | PGA-Taxol (Xyotax) | (11) | ||
| (c) Selective accumulation and retention in tumor tissue (EPR effect) | PGA-Camptothecin (CT-2106) | (12) | ||
| (d) Specific targeting of cancer cells while sparing normal cells—receptor-mediated targeting with a ligand | HPMA-DOX (PK1) | (14) | ||
| HPMA-DOX-galactosamine (PK2) | (58) | |||
| Polymeric micelles | Amphiphilic block copolymers assemble and form a micelle with a hydrophobic core and hydrophilic shell | (a) Suitable carrier for water-insoluble drug | PEG-pluronic-DOX | (16) |
| (b) Biocompatible, self-assembling, biodegradable | PEG-PAA-DOX (NK911) | (17) | ||
| (c) Ease of functional modification | PEG-PLA-Taxol (Genexol-PM) | (18) | ||
| (d) Targeting potential | ||||
| Dendrimers | Radially emerging hyperbranched synthetic polymer with regular pattern and repeated units | (a) Biodistribution and PK can be tuned | PAMAM-MTX | (64) |
| (b) High structural and chemical homogeneity | PAMAM-platinate | (21) | ||
| (c) Ease of functionalization, high ligand density | ||||
| (d) Controlled degradation | ||||
| (e) Multifunctionality | ||||
| Liposomes | Self-assembling closed colloidal structures composed of lipid bilayers | (a) Amphiphilic, biocompatible | Pegylated liposomal DOX (Doxil) | (22) |
| (b) Ease of modification | Non-pegylated liposomal DOX (Myocet) | (23) | ||
| (c) Targeting potential | Liposomal daunorubicin (DaunoXome) | (24) | ||
| Viral nanoparticles | Protein cages, which are multivalent, self-assembled structures | (a) Surface modification by mutagenesis or bioconjugation—multivalency | HSP-DOX | (29, 30) |
| (b) Specific tumor targeting, multifunctionality | CPMV-DOX | (27) | ||
| (c) Defined geometry and remarkable uniformity | ||||
| (d) Biological compatibility and inert nature | ||||
| Carbon nanotubes | Carbon cylinders composed of benzene ring | (a) Water-soluble and biocompatible through chemical modification (organic functionalization) | CNT-MTX | (34) |
| (b) Multifunctionality | CNT-amphotericin B | (33) |
| System . | Structure . | Characteristics . | Examples of compounds . | Ref. . |
|---|---|---|---|---|
| Polymeric nanoparticles (polymer-drug conjugates) | Drugs are conjugated to the side chain of a linear polymer with a linker (cleavable bond) | (a) Water-soluble, nontoxic, biodegradable | Albumin-Taxol (Abraxane) | (7) |
| (b) Surface modification (pegylation) | PGA-Taxol (Xyotax) | (11) | ||
| (c) Selective accumulation and retention in tumor tissue (EPR effect) | PGA-Camptothecin (CT-2106) | (12) | ||
| (d) Specific targeting of cancer cells while sparing normal cells—receptor-mediated targeting with a ligand | HPMA-DOX (PK1) | (14) | ||
| HPMA-DOX-galactosamine (PK2) | (58) | |||
| Polymeric micelles | Amphiphilic block copolymers assemble and form a micelle with a hydrophobic core and hydrophilic shell | (a) Suitable carrier for water-insoluble drug | PEG-pluronic-DOX | (16) |
| (b) Biocompatible, self-assembling, biodegradable | PEG-PAA-DOX (NK911) | (17) | ||
| (c) Ease of functional modification | PEG-PLA-Taxol (Genexol-PM) | (18) | ||
| (d) Targeting potential | ||||
| Dendrimers | Radially emerging hyperbranched synthetic polymer with regular pattern and repeated units | (a) Biodistribution and PK can be tuned | PAMAM-MTX | (64) |
| (b) High structural and chemical homogeneity | PAMAM-platinate | (21) | ||
| (c) Ease of functionalization, high ligand density | ||||
| (d) Controlled degradation | ||||
| (e) Multifunctionality | ||||
| Liposomes | Self-assembling closed colloidal structures composed of lipid bilayers | (a) Amphiphilic, biocompatible | Pegylated liposomal DOX (Doxil) | (22) |
| (b) Ease of modification | Non-pegylated liposomal DOX (Myocet) | (23) | ||
| (c) Targeting potential | Liposomal daunorubicin (DaunoXome) | (24) | ||
| Viral nanoparticles | Protein cages, which are multivalent, self-assembled structures | (a) Surface modification by mutagenesis or bioconjugation—multivalency | HSP-DOX | (29, 30) |
| (b) Specific tumor targeting, multifunctionality | CPMV-DOX | (27) | ||
| (c) Defined geometry and remarkable uniformity | ||||
| (d) Biological compatibility and inert nature | ||||
| Carbon nanotubes | Carbon cylinders composed of benzene ring | (a) Water-soluble and biocompatible through chemical modification (organic functionalization) | CNT-MTX | (34) |
| (b) Multifunctionality | CNT-amphotericin B | (33) |
Abbreviations: PGA, poly-(l-glutamate); HPMA, N-(2-hydroxypropyl)-methacrylamide copolymer; PEG, polyethylene glycol; PAA, poly-(l-aspartate); PLA, poly-(l-lactide); PAMAM, poly(amidoamine); DOX, doxorubicin; MTX, methotrexate; PK, pharmacokinetics; EPR, enhanced permeability and retention; CNT, carbon nanotube; HSP, heat shock protein; CPMV, cowpea mosaic virus.