Dual‐responsive supramolecular self‐assembly of inclusion complex of an azobenzene‐ended poly(ε‐caprolactone) with a water‐soluble pillar[6]arene and its application in controlled drug release

Dual photo‐ and pH‐responsive polymeric vesicles are constructed from a host–guest complex between a water‐soluble pillar[6]arene and an azobenzene ended functionalized poly(ε‐caprolactone). Reversible morphological transitions between vesicles and solid aggregates are achieved upon repeated UV stimulus and pH stimulus. Moreover, the polymeric vesicles present excellent cytocompatibility toward HepG2 cells and can be further applied for controlled release of a hydrophilic model drug, DOX?HCl. © 2017 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2017 , 55 , 2477–2482     

Podophyllotoxin extraction from Linum usitatissimum plant and its anticancer activity against HT‐29, A‐549 and MDA‐MB‐231 cell lines with and without the presence of gold nanoparticles

In recent years, gold nanoparticles (Au‐NPs) have been taken into consideration in nanomedicine due to their excellent biocompatibility, chemical stability and promising optical properties. In this research, podophyllotoxin conjugated with gold nanoparticles (Au‐NPs‐POT) was synthesized and the conjugation of POT with Au‐NPs was confirmed using scanning electron microscopy, mass spectrometry and Fourier transform infrared spectroscopy. The anticancer effects of the product on preclinical models of lung, colon and breast cancers were investigated using MTT test. The analyses showed a direct dose–response relationship. It was found that higher concentrations of POT have more positive effects on the inhibition of cancer cell growth. At POT concentrations of 1, 2.5, 5, 7.5, 10, 15 and 20 ng ml^?1, approximately 50% of the growth of colorectal, lung and breast cancer cell lines was inhibited, while similar results were obtained in the presence of 1, 2, 3, 4 and 5 μg ml^?1 Au‐NPs‐POT. Au‐NPs‐POT exhibited the lowest cytotoxicity due to the presence of POT. The anticancer feature of Au‐NPs‐POT proved the potential to develop better anticancer therapeutics and to open new avenues for treatment of cancers.     

Camptothecin@HMSNs/thermosensitive hydrogel composite for applications in preventing local breast cancer recurrence

The CPT was loaded into the HMSNs with the high loading capacity. Then the CPT@HMSNs were loaded into the PLEL thermosensitive hydrogels for local therapy to prevent the recurrence of breast cancer after the tumor was resected.     

Synthesis and characterization of biodegradable amphiphilic ABC Y‐shaped miktoarm terpolymer by click chemistry for drug delivery

Biodegradable amphiphilic ABC Y‐shaped triblock copolymer (MPBC) containing PEG, PBLA, and PCL segments was synthesized via the combination of enzymatic ring‐opening polymerization (ROP) of epsilon‐caprolactone, ROP of BLA‐N‐carboxyanhydride and click chemistry, where PEG, PBLA, and PCL are poly(ethylene glycol), poly(benzyl‐l ‐aspartate), and polycaprolactone, respectively. Propynylamine was employed as ROP initiator for the preparation of alkynyl‐terminated PBLA and methyloxy‐PEG with hydroxyl and azide groups at the chain‐end was used as enzymatic ROP initiator for synthesis of monoazido‐midfunctionalized block copolymer mPEG‐b‐PCL. The subsequent click reaction led to the formation of Y‐shaped asymmetric heteroarm terpolymer MPBC. The polymer structures were characterized by different analyses. The MPBC terpolymer self‐assembled into micelles and physically encapsulated drug doxorubicin (DOX) to form DOX‐loaded micelles, which showed good stability and slow drug release. In vitro cytotoxicity study indicated that the MPBC micelles were nontoxic and the DOX‐loaded micelles displayed obvious anticancer activity similar to free DOX against HeLa cells. © 2014 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2014 , 52, 3346–3355     

Molecular-scale drug delivery systems loaded with oxaliplatin for supramolecular chemotherapy

Smart strategies that can decrease the side effect and enhance the therapeutic efficacy of chemotherapy are in urgent need to meet the special demands of cance r therapy.Herein,two wate r-soluble macrocyclic hosts,i.e.,a carboxylated leaning tower[6]arene(CLT6) and a carboxylated [2]biphenyl-extended pillar[6]arene(CBpP6),are used to load chemotherapy drug oxaliplatin(OxPt) by forming inclusion complexes(OxPt■CLT6 and OxPt■CBpP6) through host-guest interactions.Interestingly,OxPt can be released from the macrocyclic cavities of these drug delivery systems(DDSs) via the competitive binding effect of spermine(SPM) because of the stronger binding abilities of CLT6/CBpP6 toward SPM as compared with OxPt,leading to enhanced cytotoxicity on SPM-overexpressed cancer cells,such as breast cancer MCF-7 cells.Moreover,compared to free OxPt,due to the low concentration of SPM in normal cells,OxPt■CGT6 and OxPt■CBpP6 demonstrated a decreased cytotoxicity on liver L02 cells,which is beneficial fo r reducing the side effect of anticancer drug during chemotherapy.Such a strategy might be extended to other antitumor drugs and water-soluble macrocycles with suitable cavity sizes to achieve controllable drug delivery and enhanced anticancer ability in supramolecular chemotherapy     

Direct synthesis of Poly(Ԑ-Caprolactone)-block-poly (glycidyl methacrylate) copolymer and its usage as a potential nano micelles carrier for hydrophobic drugs

Ring-opening (ROP) and enzymatic copolymerization (ECP) are among the most widely used approaches for synthesizing copolymers of polycaprolactone (PCL). It involves multiple-step reactions and the utilization of enzymes that make the process a lot more complicated, time consuming, and expensive. Atom transfer radical polymerization (ATRP) has been adopted to synthesize a novel amphiphilic copolymer in our study. The study presents a method to eliminate the ROP/ECP multiple steps in monomer polymerization thus making the process simpler and smoother. The synthesis of cationic polymer micelles copolymer of PCL-PGMA (polycaprolactone grafted poly glycidyl methacrylate) was carried out using direct functionalization of hydroxy group in crude PCL to achieve a higher degree of functionalization, i.e., 12.8% for macroinitiator. FTIR and ¹H-NMR confirmed the successful synthesis of the copolymer with better control over the molecular weight with a PDI (1.84). DSC and XRD results showed the reduction of crystallinity by 86.81%, making copolymer more compatible for drug delivery application. The synthesized copolymer was further converted to nano-micelles drug carrier having an average size of 96.08 ± 21.22 nm. The drug encapsulation efficiency achieved was 60.0 ± 1.7%, and nano-micelles rendered a slow and controlled release of naproxen with long-term storage stability.