Table 3.
List of representative hypoxia-responsive NCs [112]
| Nanocarriers | Magnetic-responsive strategy/materials | Cargos | Applications |
|---|---|---|---|
| Liposomes | The prodrug of banoxantrone dihydrochloride (AQ4N) could be activated in hypoxic environment caused by PDT | Ce6, AQ4N | Cancer therapy |
| Silica nanoquencher | Azo monomer; cell-penetrating poly(disulfide)s (CPD) coated silica nanoquencher (BS-qNP) (CPD-protein@BS-qNP) | Antibody (Cetuximab), fluorescent dye | Hypoxia-triggered protein release and fluorescence imaging |
| Upconversion nanoparticles (UCNPs) | Oxygen indicator [Ru(dpp)3]2+Cl2 for hypoxia detection as UCNPs provided the excitation light of [Ru(dpp)3]2+Cl2 by upconversion process at 980 nm | [Ru(dpp)3]2+Cl2, UCNPs | Imaging hypoxic regions or oxygen changes in cells and zebrafish |
| Nanoparticles | The photosensitizer of ICG-mediated PTT induced hypoxia, which then activated the prodrug of TPZ | TPZ, ICG | Tumor therapy by PDT and chemotherapy |
| Nanoparticles | The shift from hydrophobic to hydrophilic of 2-nitroimidazole that grafted to polymers in light-activated hypoxia | Doxorubicin, light-sensitive polymer | Hypoxia-triggered drug release, tumor |
| Nanoparticles | PEG-azo(azobenzene)-PEI-DOPE block copolymer | siRNA | siRNA delivery and tumor RNAi |
| Nanoparticles | Layer-by-layer nanoparticles with a pH-sensitive layer for targeting of tumor hypoxia | Sulfonated polystyrene beads or carboxylated quantum dots | Systemic tumor targeting |
| Cancer cell membrane coated MOFs | The porphyrinic MOFs could generate toxic ROS for PDT and cause hypoxic regions for activating TPZ | Porphyrinic metal organic framework, TPZ | Tumor targeted PDT and chemotherapy |
| Nanovesicles | The light irradiation of Ce6 induced hypoxia for oxidation bioreduction of 2-nitroimidazole in polymers and activation of TPZ | Ce6, TPZ | Tumor fluorescence imaging and therapy |
| Polymeric micelles | The metronidazole (MN) grafted in polymers could change hydrophobicity in hypoxic conditions for drug release | Doxorubicin | Tumor chemotherapy and radiotherapy |
| Polymersomes | The PLA (polylactic acid)-azobenzene-PEG is sensitive to hypoxia | Gemcitabine, hypoxia-sensitive dye “Image-iT” | Tumor imaging and drug delivery |
| Albumin nanoparticles | With hypoxia-sensitive azobenzene linker to covalently bridge photosensitizer Ce6-conjugated HSA and oxaliplatin prodrug-conjugated HSA | Oxaliplatin prodrug, Ce6 | Tumor chemotherapy and photodynamic therapy |
| Mesoporous silica nanoparticles | The Ce6-dopped mesoporous silica nanoparticles were decorated with PEG and glycol chitosan by hypoxia-sensitive azobenzene linker | Oligonucleotide (CpG), Ce6 | Cancer immunotherapy |
| Solid-state sensors | Iodide-substituted difluoroboron dibenzoylmethane-poly(lactic acid) [BF2dbm(I)PLA] solid-state sensor material | BF2dbm(I)PLA | Tumor hypoxia optical imaging |
| Polymeric probes | Poly(N-vinylpyrrolidone)-conjugated iridium-(III) complex (Ir-PVP) and poly(ε-caprolactone)-b-poly(N-vinylpyrrolidone) (PCL-PVP) nanoparticles | Iridium (III) complex | Optical imaging of tumor and metastasis |
| Polymer hybrid CaP nanoparticles | Tumor pH-triggered release of Mn2+ from CaP to boost higher contrast enhancement in hypoxic tumor regions | Mn2+ | MR imaging of solid tumors, hypoxia and metastasis |