Preparation of new dendrimer-like star-shaped amphiphilic poly(ethylene glycol)-poly(ϵ -caprolactone) copolymers for biocompatible and high-efficiency curcumin delivery

Biodegradable polyester unimolecular systems as emerging materials for therapeutic applications

Unimolecular micelles, as a class of single-molecular micelles, are structurally stable regardless of their concentrations or alterations of the outer environment such as pH, temperature, ion strength etc. in comparison with conventional polymeric micelles. Polyester unimolecular micelles are extensively applied in bio-medical fields because of their stability, biocompatibility, biodegradability, structural-controllabilty etc. In this review, the most recent developments in polyester unimolecular micelle designs in terms of Boltorn polymer H40 core, cyclodextrin, dendrimer or dendrimer-like polymer, or polyhedral oligomeric silsesquioxane (POSS) based polyester unimolecular micelles are presented. The significance and application in biomedical fields including drug delivery, bio-imaging and theranostics are also classified in this review. Finally, the remaining challenges and future perspectives for further development of unimolecular micelles as therapeutic materials are also discussed.

Ultrasound-assisted synthesis of pH-responsive nanovector based on PEG/chitosan coated magnetite nanoparticles for 5-FU delivery

pH-responsive magnetic carriers at the nanoscale are one of the most important agents for the targeted treatment of cancer. In this study, Fe₃O₄ nanoparticles were prepared by co-precipitation method and functionalized with three types of PEG using ultrasound waves. PEGlated particles were modified with chitosan shell through ultrasound-assisted double emulsion method. The prepared material which was used as a pH responsive carrier for pinpointed 5-FU delivery. The chemico-physical properties of prepared nanoparticles have been investigated. Results demonstrated that pure Fe₃O₄ had a mean diameter of 20nm with the regular spherical shape which was increased after modification step depending on the type of PEG. 5-FU loading properties and releasing behaviors studies in different pHs which showed that 5-FU can be efficiently loaded in the Fe₃O₄@Cs-PEG. Also, in the case of release, the amount of 5-FU released at pH=5.8 is noticeably higher compared to the released amount at pH=7.4 in all three samples at any distinct time. For instance at pH=7.4, 27% of the 5-FU was released from the Fe₃O₄@Cs-PEG2 during 48h; as the pH decreases to 5.8, the cumulative amount of 5-FU released enhanced to 52%. The in vitro MTT assay results demonstrated that the cell viability decreases in all synthesized nanoparticles as the pH medium of MCF-7 culture became to 5.8. For example, cell viability of Fe₃O₄@Cs-sPEG decreased from 44±2% to 36±1.9% at a concentration of 5 (μg/ml) as the pH varied from 7.4 to 5.8.

Synthesis and meticulous molecular, morphological and thermal characterization of linear and star-shaped polycaprolactones

Linear and star-shaped polycaprolactones: two-dimensional separation.

Carbon nanotube-based stimuli-responsive nanocarriers for drug delivery

In cancer therapy, smart nanocarriers are one of the most important nanoscale vectors of therapeutic agents.

Design of systems based on 4-armed star-shaped polyacids for indomethacin delivery

The pentaerythritol based star-shaped polyacids as micellar nanocarriers with adjustable characteristics for drug delivery have been investigated.