Dual Location Reduction-Responsive Degradable Nanocarriers: A New Strategy for Intracellular Anticancer Drug Delivery with Accelerated Release. In: Matyjaszewski K, Sumerlin BS, Tsarevsky NV, Chiefari J, editors. Controlled Radical Polymerization: Materials. Washington: American Chemical Society; 2015. pp. 273-91. [DOI: 10.1021/bk-2015-1188.ch017]

Enhanced Intracellular Delivery of Curcumin by Chitosan-Lipoic Acid as Reduction-Responsive Nanoparticles

AIMS

Enhancement of anti-tumor activity of the chemotherapeutic agent CUR by redoxsensitive nanoparticle to get a deeper insight into cancer therapy.

BACKGROUND

Tumor targetability and stimulus are widely used to study the delivery of drugs for cancer diagnosis and treatment because poor cellular uptake and inadequate intracellular drug release lead to inefficient delivery of anticancer agents to tumor tissue.

OBJECTIVE

Studies distinguishing between tumor and normal tissues or redox-sensitive systems using glutathione (GSH) as a significant signal.

METHODS

In this study, we designed Chitosan-Lipoic acid Nanoparticles (CS-LANPs) to improve drug delivery for breast cancer treatment by efficient delivery of Curcumin (CUR). The properties of blank CS-LANPs were studied in detail. The size and the Polydispersity Index (PDI) of the CS-LANPs were optimized.

RESULTS

The results indicate the mean size and PDI of the blank CS-LANPs were around 249 nm and 0.125, respectively. However, the Drug Loading (DL) and Encapsulation Efficiency (EE) of the CSLANPs were estimated to be about 18.22% and 99.80%, respectively. Compared to non-reductive conditions, the size of reduction-sensitive CS-LANPs increased significantly under reductive conditions. Therefore, the drug release of CS-LANPs in the presence of glutathione was much faster than that of non-GSH conditions .Moreover, the antitumor effect of CS-LANPs on MCF-7 cells was determined in vitro by MTT assay, cell cytotoxicity, Caspase-3 Assay, detection of mitochondrial membrane potential and quantification of apoptosis incidence.

CONCLUSION

CS-LANPs showed a remarkably increased accumulation in tumor cells and had a better tumor inhibitory activity in vitro. CS-LANPs could successfully deliver drugs to cancer cells and revealed better efficiency than free CUR.

Designing single trigger/dual-response release and degradation into amine-functional hyperbranched-polydendron nanoprecipitates

The synthesis of complex polymer architectures using relatively facile experimental protocols provides access to materials with the opportunity to control functionality and physical behaviour. The scope of hyperbranched-polydendron chemistries has been expanded here to include primary chains comprising amine-functional 'homopolymer', 'statistical copolymer' and amphiphilic 'block copolymer' analogues using 2-(diethyl amino)ethyl methacrylate, 2-hydroxy propyl methacrylate and t-butyl methacrylate. The different primary chain chemistry and architectures leads to a marked variation in nanoprecipitation behaviour and the response of the resulting amine-functional nanoparticles to varying pH. When acid-sensitive and acid-stable branchers, 1,4-butanediol di(methacryoyloxy)-ethyl ether and ethylene glycol dimethacrylate respectively, are utilised, nanoparticles with encapsulation properties are formed and may be triggered to either release-and-disassemble or release-disassemble-degrade to form a solution of lower molecular weight constituent primary chains.

Disassembly and tumor-targeting drug delivery of reduction-responsive degradable block copolymer nanoassemblies

Review on recent strategies to synthesize novel disulfide-containing reductively-degradable block copolymers and their nanoassemblies as being classified with the number, position, and location of the disulfide linkages toward effective tumor-targeting intracellular drug delivery exhibiting enhanced release of encapsulated drugs.

Facile Strategies to Synthesize Dual Location Dual Acidic pH/Reduction-Responsive Degradable Block Copolymers Bearing Acetal/Disulfide Block Junctions and Disulfide Pendants

We report new dual acidic pH/reduction-responsive degradable amphiphilic block copolymers featured with dual acidic pH-labile acetal linkage and a reductively-cleavable disulfide bond at the hydrophilic/hydrophobic block junction as well as pendant disulfide bonds in the hydrophobic block. Centered on the use of a macroinitiator approach, three strategies utilize the combination of atom transfer radical polymerization and reversible addition fragmentation chain transfer polymerization in a sequential or concurrent mechanism, along with facile coupling reactions. Combined structural analysis with dual-stimuli-responsive degradation investigation allows better understanding of the architectures and orthogonalities of the formed block copolymers as a diblock or a triblock copolymer. Our study presents the development of effective synthetic strategies to well-defined multifunctional amphiphilic block copolymers that exhibit dual-stimuli-responsive degradation at dual location (called the DL-DSRD strategy), thus potentially promising as nanoassemblies for effective drug delivery.

Rosin-based block copolymer intracellular delivery nanocarriers with reduction-responsive sheddable coronas for cancer therapy

Rosin-based, reduction-responsive block copolymer-based nanocarriers exhibiting excellent colloidal stability enabling the delivery of anticancer drugs to cancerous tissues for the enhanced release of encapsulated drugs, offering great versatility as intracellular drug-delivery nanocarriers for cancer therapy.