201611-92-9Relevant articles and documents
Visible-light degradable polymer coated hollow mesoporous silica nanoparticles for controlled drug release and cell imaging
Yang, Shun,Li, Najun,Chen, Dongyun,Qi, Xiuxiu,Xu, Yujie,Xu, Ying,Xu, Qingfeng,Li, Hua,Lu, Jianmei
, p. 4628 - 4636 (2013)
A core-shell nanocomposite based on photo-degradable polymer coated hollow mesoporous silica nanoparticles (HMS) was successfully prepared for targeted drug delivery and visible-light triggered release, as well as fluorescence cell imaging. The HMS nanoparticles were first modified by the long-chain hydrocarbon octadecyltrimethoxysilane (C18) and fluorescent agent Rhodamine B isothiocyanate (RITC), and then encapsulated by a photodegradable amphiphilic copolymer via a self-assembly process. The obtained nanocarrier showed a high drug loading content due to the hollow core and mesopores of the HMS and could target folic acid receptor over-expressed tumor cells efficiently for conjugating folic acid (FA) in the amphiphilic polymer. The drug release could be triggered by the irradiation of green light (500-540 nm) due to the photodegradation of amphiphilic copolymer coated on the HMS. Furthermore, the targeted drug delivery and controlled release processes could be tracked by fluorescence imaging for the doping of RITC on the HMS. The In vitro results suggested that a smart visible light responsive drug delivery system was successfully prepared for the potential applications of cancer diagnosis and therapy.
Fine-tuning the transition temperature of a stimuli-responsive polymer by a simple blending procedure
Fernandez-Trillo, Francisco,Van Hest, Jan C. M.,Thies, Jens C.,Michon, Thierry,Weberskirch, Ralf,Cameron, Neil R.
, p. 2230 - 2232 (2008)
Binary mixtures of well-defined, stimuli-responsive elastin-based side-chain polymers show a single transition temperature that depends on blend composition. The Royal Society of Chemistry.
Preparation of a camptothecin prodrug with glutathione-responsive disulfide linker for anticancer drug delivery
Xu, Zhigang,Wang, Dongdong,Xu, Shuang,Liu, Xiaoyan,Zhang, Xiaoyu,Zhang, Haixia
, p. 199 - 205 (2014)
We present here a novel camptothecin (CPT) prodrug based on polyethylene glycol monomethyl ether-block-poly(2-methacryl ester hydroxyethyl disulfide-graft-CPT) (MPEG-SS-PCPT). It formed biocompatible nanoparticles (NPs) with diameters of approximately 122 nm with a CPT loading content as high as approximately 25 wt % in aqueous solution. In in vitro release studies, these MPEG-SS-PCPT NPs could undergo triggered disassembly and much faster release of CPT under glutathione (GSH) stimulus than in the absence of GSH. The CPT prodrug had high antitumor activity, and another anticancer drug, doxorubicin hydrochloride (DOX×HCl), could also be introduced into the prodrug with a high loading amount. The DOX×HCl-loaded CPT prodrug could deliver two anticancer drugs at the same time to produce a collaborative cytotoxicity toward cancer cells, which suggested that this GSH-responsive NP system might become a promising carrier to improve drug-delivery efficacy.
Visible-Light-Driven MADIX Polymerisation via a Reusable, Low-Cost, and Non-Toxic Bismuth Oxide Photocatalyst
Hakobyan, Karen,Gegenhuber, Thomas,McErlean, Christopher S. P.,Müllner, Markus
supporting information, p. 1828 - 1832 (2019/01/14)
The continuous amalgamation of photocatalysis into existing reversible deactivation radical polymerisation (RDRP) processes has initiated a rapidly propagating area of polymer research in recent years. We introduce bismuth oxide (Bi2O3) as a heterogeneous photocatalyst for polymerisations, operating at room temperature with visible light. We demonstrate formidable control over degenerative chain-transfer polymerisations, such as macromolecular design by interchange of xanthate (MADIX) and reversible addition-fragmentation chain-transfer (RAFT) polymerisation. We achieved narrow molecular weight distributions and attribute the excellent temporal control of a photo-induced electron transfer (PET) process. This methodology was employed to synthesise diblock copolymers combining differently activated monomers. The Bi2O3 catalyst system has the additional benefits of low toxicity, reusability, low-cost, and ease of removal from the reaction mixture.
Coumarin-containing photo-responsive nanocomposites for NIR light-triggered controlled drug release via a two-photon process
Ji, Weidong,Li, Najun,Chen, Dongyun,Qi, Xiuxiu,Sha, Wenwei,Jiao, Yang,Xu, Qingfeng,Lu, Jianmei
, p. 5942 - 5949 (2013/11/19)
A new multifunctional nanovehicle for tumor therapy and cell imaging was fabricated by coating NIR light-responsive polymers (HAMAFA-b-DDACMM) onto the surface of octadecyltrimethoxysilane (C18)-modified hollow mesoporous silica nanoparticles (HMS@C18) via self-assembly. First, the targeting NIR light-responsive block copolymer was synthesized by the RAFT living polymerization of [7-(didodecylamino) coumarin-4-yl] methyl methacrylate with hydroxyethylacrylate and N-(3-aminopropyl) methacrylamide hydrochloride and then grafted with folic acid (FA). The copolymers could be disrupted by excitation by a femtosecond NIR light laser (800 nm) via a two-photon absorption process due to the high two-photon absorption cross-section of the coumarin moiety. In order to enhance the drug loading capacity and biological stability of the nanovehicle, HMS nanoparticles modified by hydrophobic octadecyl chains were selected as the "core", which had a considerable drug loading efficiency of more than 70%. Then the core-shell nanocomposites (HMS@C18@HAMAFA-b-DDACMM) were obtained by coating the amphiphilic copolymers onto the core via self-assembly. Under excitation by NIR light at 800 nm, the pre-loaded drugs could be released from the nanocomposites due to the degradation of the light-responsive copolymers and the release efficiency was correlated with the irradiation time and light power. The in vitro experiments indicated that the nanocomposites were easily targeted into the tumor cells that over-expressed folic acid receptor (FR(+)) such as KB cells by endocytosis. Furthermore, the copolymer itself had strong fluorescence, which could be used to track the process of drug delivery.
A new selenium-based RAFT agent for surface-initiated RAFT polymerization of 4-vinylpyridine
Demirci, Serkan,Kinali-Demirci, Selin,Caykara, Tuncer
, p. 5345 - 5350 (2013/09/23)
A new selenium-based reversible addition-fragmentation chain transfer (RAFT) agent, 4-cyanopentanoic acid diselenobenzoate (RAFT-Se), was synthesized and utilized in the surface-initiated RAFT polymerization of 4-vinylpyridine (4VP) on silicon substrate. The results indicate that the RAFT-Se can control the surface-initiated RAFT polymerization, as evidenced by the number-average molecular weight that increase linearly with monomer conversion, molecular weights that agreed well with the predicted values, and the relatively low polydispersity indexes. The surface-initiated RAFT polymerization with the RAFT-Se was the same polymerization mechanism as its analog, 4-cyanopentanoic acid dithiobenzoate (RAFT-S). The grafting density of the poly(4-vinylpyridine) brushes prepared in the presence of RAFT-Se (σRAFT-Se) and RAFT-S (σRAFT-S) was estimated to be about 0.51 and 0.66 chains/nm2, respectively. In addition, the end of polymer chains on silicon substrate contains selenium element which may be useful in biosensor applications.
Thermally controlled wettability of a nanoporous membrane grafted with catechol-tethered poly(N-isopropylacrylamide)
Kim, Jee Seon,Kim, Taek Gyung,Kong, Won Ho,Park, Tae Gwan,Nam, Yoon Sung
, p. 9227 - 9229 (2012/09/08)
A nanoporous membrane is coated with catechol-tethered poly(N- isopropylacrylamide). The thermosensitive variation of surface wettability determines the hindered diffusivity of dextran (40 kDa) through the nanopores.
PH-responsive polymeric carrier encapsulated magnetic nanoparticles for cancer targeted imaging and delivery
Chen, Dongyun,Xia, Xuewei,Gu, Hongwei,Xu, Qingfeng,Ge, Jianfeng,Li, Yonggang,Li, Najun,Lu, Jianmei
, p. 12682 - 12690 (2012/01/05)
Multifunctional drug delivery systems with favorable compatibility, high selectivity and efficiency are appropriate candidates for future medical applications. For this purpose, a multifunctional nanocomposite that enables selective magnetic resonance imaging and anticancer therapy by encapsulating hydrophobic superparamagnetic nanoparticles and chemotherapeutic agent doxorubicin with a novel biodegradable pH-activated polymeric carrier was synthesized. The as-synthesized amphiphilic polymer has excellent biocompatibility and pH-responsivity. The obtained nanocomposites selectively release the encapsulated drug and magnetic nanoparticles in mildly acidic endosomal/lysosomal compartments due to the degradation of the pH-responsive bonds, resulting in a change of imaging signal and cancer therapy. Furthermore, when compared with the nanocomposites without a targeting moiety, as studied from over-expression of the folic acid receptor tumor cell culturing, the conjugates with folic acid showed a significantly more potent targeting capability.
Synthesis and characterization of a naphthalimide-dye end-labeled copolymer by reversible addition-fragmentation chain transfer (RAFT) polymerization
Li, Binxin,Majonis, Daniel,Liu, Peng,Winnik, Mitchell A.
experimental part, p. 317 - 325 (2011/06/22)
We describe the synthesis of an end-functionalized copolymer of N-(2-hydroxypropyl)methacrylamide (HPMA) and N-hydroxysuccinimide methacrylate (NMS) by reversible addition-fragmentation chain transfer (RAFT) polymerization. To control the polymer composition, the faster reacting monomer (NMS) was added slowly to the reaction mixture beginning 30 min after initating the polymerization (ca. 16% HPMA conversion). One RAFT agent, based on azocyanopentanoic acid, introduced a-COOH group to the chain at one end. Use of a different RAFT agent containing a 4-amino-1,8-naphthalimide dye introduced a UV-vis absorbing and fluorescent group at this chain end. The polymers obtained had molecular weights of 30000 and 20000, respectively, and contained about 30 mol% NMS active ester groups.
Versatile grafting approaches to star-shaped POSS-containing hybrid polymers using RAFT polymerization and click chemistry
Ye, Yun-Sheng,Shen, Wei-Chung,Tseng, Chi-Yung,Rick, John,Huang, Yao-Jheng,Chang, Feng-Chih,Hwang, Bing-Joe
supporting information; experimental part, p. 10656 - 10658 (2011/11/29)
An alkyne-bearing polyhedral oligomeric silsesquioxane (POSS) core was used to prepare POSS-containing polymer hybrids using 'grafting to' or 'grafting from' strategies in combination with reversible chain transfer and click chemistry.
