- Initiator-chain transfer agent combo in the RAFT polymerization of styrene
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The combo agent with roles of initiator and chain transfer agent was demonstrated in RAFT polymerization of styrene. Polymers with defined structures at both α and ω ends were obtained, which was verified by the successful synthesis of seven-block segment
- Wu, Ying,Zhang, Wei,Zhang, Zhengbiao,Pan, Xiangqiang,Cheng, Zhenping,Zhu, Jian,Zhu, Xiulin
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- Preparation of thermoresponsive polymers bearing amino acid diamide derivatives via RAFT polymerization
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We report here the synthesis of well-defined homopolymer bearing amino acid diamide, poly(N-acryloyl-L-valine N'-methylamide), via reversible addition fragmentation chain transfer (RAFT) polymerization using alkynyl-functionalized 2-dodecylsulfanylthiocarbonylsulfanyl-2-methyl-propionic acid propargyl alcohol ester as chain transfer agent (CTA) and 2, 2′azobis(isobutyronitrile) as initiator. The effects of a variety of parameters, such as temperature and solvent, on RAFT polymerization were examined to determine the optimal control of the polymerization. The controlled nature of RAFT polymerization was evidenced by the controllable molecular weight and low-molecular-weight polydispersity index [Mw/Mn) of resulting homopolymers and further demonstrated to have retained end-group functionality by the fact of the successful formation of block copolymers from further RAFT polymerization by using the resultant polymer as macro-CTA, as well as from "click" chemistry. Thermoresponsive property of the prepared polymer was evaluated in terms of the lower critical solution temperature in aqueous solution by measuring the transmittance variation at 500 nm from UV/vis spectroscopy.
- Liu, Zhilei,Hu, Jiwen,Sun, Jianping,He, Guping,Li, Yinghui,Zhang, Ganwei
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- Nanocrystalline cellulose grafted random copolymers of N- isopropylacrylamide and acrylic acid synthesized by RAFT polymerization: Effect of different acrylic acid contents on LCST behavior
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Free and nanocrystalline cellulose (NCC) attached homopolymers of N-isopropylacrylamide and acrylic acid (AA) as temperature- and pH-sensitive materials and also their dual-sensitive copolymers with different contents of AA were synthesized by RAFT polyme
- Zeinali, Elnaz,Haddadi-Asl, Vahid,Roghani-Mamaqani, Hossein
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- Dual electrical switching permeability of vesicles via redox-responsive self-assembly of amphiphilic block copolymers and polyoxometalates
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Electro-responsive vesicles were demonstrated based on an amphiphilic block copolymer PEO114-b-P(DCH-Ru)n and an inorganic nanoparticle polyoxometalate H3PMo12O40 (PMo12) via electrostatic
- Chong, Dandan,Tan, Junyan,Zhang, Jinlong,Zhou, Yue,Wan, Xinhua,Zhang, Jie
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- Synthesis, characterization, and antibacterial properties of a hydroxyapatite adhesive block copolymer
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A novel diblock copolymer composed of bisphosphonate and pyridine oligomers has been prepared by reversible addition-fragmentation transfer (RAFT) polymerization. Ag ion was introduced into the polymer via its coordination with the pyridine groups, followed by a reduction process to obtain Ag nanoparticles with diameters of 5-15 nm measured by transmission electron microscopy (TEM). In addition, X-ray photoelectron spectroscopy (XPS) and X-ray diffraction (XRD) proved successful introduction of Ag nanoparticles into polymer. Ag nanoparticles containing polymer exhibited excellent antibacterial properties toward Lactobacillus plantarum (L. plantarum). In order to investigate its practical application as an antibacterial coating, the synthesized polymer was tethered onto hydroxyapatite (HA, main mineral component of natural bone, teeth, and most of implants for bone repair) surfaces via interaction between the polymers bisphosphonate group and HA, forming ～4 nm thick layers. Ag nanoparticles (5-15 nm in diameter) uniformly distributed around the HA particles were fabricated following the above process. The ability of the coating to kill the bacteria L. plantarum was determined, which revealed strong antibacterial properties.
- Zhang, Qiang Matthew,Serpe, Michael J.
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- Homopolymer vesicles with a gradient bilayer membrane as drug carriers
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We report an unusual homopolymer vesicle, which has a soft bilayer membrane composed of oligo(ethyleneoxy) side chains (OEs) with a gradually decreased packing density from the centre of the membrane to both margins, exhibiting thermo-responsive zeta potential and dispersibility and showing potential applications for anti-cancer drug delivery.
- Fan, Lang,Lu, Hang,Zou, Kaidian,Chen, Jing,Du, Jianzhong
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- Preparation of hyperbranched polystyrene-g-poly(N-isopropylacrylamide) copolymers and its application to novel thermo-responsive cell culture dishes
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This paper describes the preparation of hyperbranched polystyrene-g-poly(N-isopropylacrylamide) (HBPSt-g-PNIPAM) and its application as a novel thermo-responsive material for cell sheet preparation. HBPSt-g-PNIPAM was synthesized by grafting PNIPAM from the termini of HBPSt via reversible addition fragmentation transfer polymerization. The resulting HBPSt-g-PNIPAM was cast from a solution onto a commercial polystyrene-based dish (PS-dish) to make a thermo-responsive surface for cell cultivation (P4/PS-dish). Mouse 3T3 fibroblast cells were seeded on the P4/PS-dish with 2.5-3.5 μg/cm2 of PNIPAM and cultured at 37 °C for four days to achieve high confluency. Fairly large cell sheets were successfully collected by cooling the dish to 20 °C. The current material avoids the use of electron beam polymerization, which requires complicated equipment, for fabricating a thermo-responsive surface because PNIPAM is immobilized by the affinity between the hyperbranched polystyrene segment and the PS-dish.
- Sudo, Yu,Sakai, Hideaki,Nabae, Yuta,Hayakawa, Teruaki,Kakimoto, Masa-Aki
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- One-step synthesis of pegylated cationic nanogels of poly(N,N′-dimethylaminoethyl methacrylate) in aqueous solution via self-stabilizing micelles using an amphiphilic macroRAFT agent
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Cationic nanogels of Pegylated poly(N,N′-Dimethylaminoethyl methacrylate) (PEG-PDAEMA) have been synthesized in aqueous solution by a one-step surfactant-free reversible addition-fragmentation transfer (RAFT) process. A Pegylated amphiphilic macroRAFT agent (mPEG550-TTC) with a hydrophobic dodecyl chain was utilized to stabilize the micelles and control the polymerization and crosslinking of DMAEMA in aqueous solution. 1H NMR, GPC, Elemental analysis, Dynamic light scattering (DLS), Zeta potential and Atomic force microscopy (AFM) measurements confirmed the formation of the cationic nanogels in size of about 20?nm with a narrow distribution. It also revealed that the concentration of monomer and the kinds of crosslinker are the key factors to control the formation of nanogel. This cationic nanogel has potential application in gene delivery.
- Yan, Lifeng,Tao, Wei
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- Oxygen-Initiated and Regulated Controlled Radical Polymerization under Ambient Conditions
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A rapid oxygen-initiated and -regulated controlled radical polymerization was conducted under ambient temperature and atmosphere. The reaction between triethylborane and oxygen provides ethyl radicals, which initiate and mediate the radical polymerization. The controlled radical polymerization was achieved using RAFT chain transfer agents (CTA) without any process of removing oxygen, providing well-defined polymers with almost full conversion (>95 %) in a short period (15 min). High-throughput screening was used to discover the suitable conditions for various CTA and monomers. To show the versatility of this method, a polymer library containing 25 well-defined polymers with different compositions (block and statistical copolymers) and molecular weights were synthesized in 1 h via high-throughput synthesis technique. A polymer-painting technique was developed using this method, forming films with spatial control and excellent control in molecular weight and dispersity.
- Lv, Chunna,He, Congze,Pan, Xiangcheng
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- Water-soluble and clickable segmented hyperbranched polymers for multifunctionalization and novel architecture construction
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A series of novel and narrowly polydispersed regular chain-segmented hyperbranched poly(tertiary amino methacrylate)s (HPTAM)s with hydrophilic core and hydrophobic shell were synthesized via the combination of self-condensing vinyl copolymerization (SCVCP) and reversible addition-fragmentation chain transfer (RAFT) methodology. 2-(Dimethylamino)ethyl methacrylate (DMAEMA) and 2-((2-(((dodecylthio)carbonothioyl)thio)-2-methylpropanoyl)oxy)ethyl acrylate (ACDT) at various molar feed ratios (γ, [DMAEMA]:[ACDT]) were chosen as monomers for linear segment formation of the structure. The copolymerization kinetics revealed that during the polymerization the real-time γ value kept almost constant and was consistent with the initial feed ratio. So HPTAMs possesses regular linear chains between every two neighboring branching units, which closely resemble HyperMacs in structure. Fast click-like Menschutkin reaction (i.e., quaternarization) of the segmented hyperbranched polymers with propargyl bromide and 2-azidoethyl 2-bromoacetate readily afforded water-soluble and clickable poly(propargyl quaternary ammonium methacrylate) (HPPrAM) and poly(azide quaternary ammonium methacrylate) (HPAzAM), respectively. Through Cu(I)-catalyzed azide-alkyne cycloaddition (CuAAC), the HPPrAMs were functionalized with 1-azidododecane and 2-azidoethyl 2-bromoisobutyrate, giving birth to amphiphilic hyperbranched polyelectrolytes (or hyperbranched surfactants) and hyperbranched ATRP macroinitiators, respectively. The HPAzAMs were efficiently decorated with monoalkynyl poly(ethylene glycol) (PEG-Alk) via CuAAC, generating dendritic polymer brushes, a novel architecture reported for the first time. In addition, core-functionazlied star-shaped HPPrAM-star-poly(tert-butyl acrylate) was synthesized by RAFT copolymerization and Menschutkin reaction.
- Han, Jin,Li, Sipei,Tang, Aijin,Gao, Chao
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- Isothermal LCST transitions triggered by bioreduction of single polymer end-groups
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The α-termini of RAFT-derived thermoresponsive polymers were functionalised via thiol exchange with pyridyl disulfide. Addition of hydrophilic end-groups dramatically increased the observed cloud point of the polymers, without changing the composition of the main chain. Selective cleavage of the disulfide-linked end-groups was observed under conditions intended to mimic intracellular glutathione concentration. This allowed the thermoresponsive behaviour to be 'switched on' without the need for a temperature stimulus-an 'isothermal' switch.
- Summers, Matthew J.,Phillips, Daniel J.,Gibson, Matthew I.
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- Folic acid-tethered poly(N-isopropylacrylamide)-phospholipid hybrid nanocarriers for targeted drug delivery
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A series of temperature-responsive lipopolymers have been synthesized by bioconjugating poly(N-isopropylacrylamide)n (n = 25, 40, 60) onto three different phospholipids by the combination of reversible addition fragmentation chain transfer poly
- John, Johnson V.,Jeong, Young-Il,Johnson, Renjith P.,Chung, Chung-Wook,Park, Huiju,Kang, Dae Hwan,Cho, Jin Ku,Kim, Yongjin,Kim, Il
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- Hypoxia and temperature dual-stimuli-responsive random copolymers: Facile synthesis, self-assembly and controlled release of drug
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Amphiphilic random copolymers poly(isopropylacryamide-co-acrylic acid-co-2-nitroimidazole acrylate) (P(NIPAM-co-AA-co-NIA)) with different contents of the 2-nitroimidazole (NI) group were facilely synthesized through RAFT and EDC reactions. These random c
- Deng, Yinlu,Ji, Chenming,Wu, Yongzhen,Yuan, Hua,Yuan, Weizhong
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- 2-{[(Dodecylsulfanyl)carbonothioyl]sulfanyl}-2-methyl-propanoic acid: A chain of edge-fused R22(8) and R4 4(20) rings built from O - H...O and C - H...O hydrogen bonds
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In the title compound, C17H32O2S 3, the dodecyl chain and the trithio-carbonate unit adopt a nearly planar all-trans conformation, while the carboxyl group is synclinal to this chain direction. The molecules are linked by pairs of inversion-related O - H...O hydrogen bonds to form centrosymmetric dimers of R2 2(8) type, and dimers related by translation are linked by C - H...O hydrogen bonds to form a chain of edge-fused rings, or a mol-ecular ladder, containing alternating R22(8) and R 44(20) rings.
- Zuluaga, Fabio,Grande, Carlos,Cobo, Justo,Glidewell, Christopher
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- Mitochondria-targeted polymer-celastrol conjugate with enhanced anticancer efficacy
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Celastrol, a natural triterpene extracted from traditional Chinese medicine, shows anticancer effects on various cancer cells. However, its poor water-solubility, short plasma half-life, and high systemic toxicity impede its applications in vivo, necessitating a stable drug delivery system to overcome these critical drawbacks. We present here a block copolymer, poly(2-(N-oxide-N,N-dimethylamino)ethyl methacrylate)-block-poly(2-hydroxyethyl methacrylate) (OPDMA-HEMA), as the carrier for celastrol delivery. The amphiphilic polymer-celastrol conjugate can self-assemble into nanoparticles in aqueous solutions. The OPDMA outer shell confers the nanoparticles with improved pharmacokinetics and efficient mitochondria targeting capacity, and profoundly potentiates celastrol's induction of immunogenic cell death, which collectively contribute to the enhanced therapeutic effects of celastrol in vivo. This mitochondria-targeted polymer-celastrol conjugate may promise the applications of celastrol in cancer treatment.
- Geng, Yu,Xiang, Jiajia,Shao, Shiqun,Tang, Jianbin,Shen, Youqing
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p. 122 - 133
(2022/01/11)
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- Ubiquitous Nature of Rate Retardation in Reversible Addition-Fragmentation Chain Transfer Polymerization
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Reversible addition-fragmentation chain transfer (RAFT) polymerization is one of the most powerful reversible deactivation radical polymerization (RDRP) processes. Rate retardation is prevalent in RAFT and occurs when polymerization rates deviate from ideal conventional radical polymerization kinetics. Herein, we explore beyond what was initially thought to be the culprit of rate retardation: dithiobenzoate chain transfer agents (CTA) with more active monomers (MAMs). Remarkably, polymerizations showed that rate retardation occurs in systems encompassing the use of trithiocarbonates and xanthates CTAs with varying monomeric activities. Both the simple slow fragmentation and intermediate radical termination models show that retardation of all these systems can be described by using a single relationship for a variety of monomer reactivity and CTAs, suggesting rate retardation is a universal phenomenon of varying severity, independent of CTA composition and monomeric activity level.
- Bradford, Kate G. E.,Petit, Leilah M.,Whitfield, Richard,Anastasaki, Athina,Barner-Kowollik, Christopher,Konkolewicz, Dominik
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supporting information
p. 17769 - 17777
(2021/11/10)
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- Anti-tumor active multifunctional polymer micelle with tumor pH and H2O2 specific activation and preparation method
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The invention provides an anti-tumor active multifunctional polymer micelle with tumor pH and H2O2 specific activation and a preparation method. A polymer micelle (TBPBA-PEGVI-FA) which can be self-assembled in a water phase is synthesized by utilizing pH and H2O2 double sensitivities of a borate bond at a tumor site, AglnS2 quantum dots are synthesized by a hydrothermal method, vinyl imidazole with a coordination function is used for carrying the AglnS2 quantum dots with fluorescence imaging and photodynamic therapy, and folic acid is used for targeting a tumor cell surface receptor (targeting an overexpressed tumor cell surface folate receptor (FR alpha (+))). In-vitro simulated release results show that the core-loaded DOX.HCl polymer can well release drugs in slightly acidic and H2O2 environments of tumor tissues, has good pH and H2O2 responsiveness, and is a smart nano-drug delivery system with wide application prospects.
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Paragraph 0131-0133
(2020/12/31)
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- METHOD FOR PRODUCING A GRAFTED RUBBER AND TIRE COMPRISING THE GRAFTED RUBBER
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The present invention relates to a method for producing a grafted rubber, the method comprising the steps of: A) providing a rubber comprising at least one olefinic carbon-carbon-double bond, B) providing a polymer being capable of exhibiting lower critical solution temperature (LCST) properties and comprising a terminal functional thiol group capable of reacting with the olefinic carbon-carbon double bond of the rubber, wherein the polymer is obtained by the steps of: B1) reversible addition-fragmentation chain transfer (RAFT) polymerization of a monomer comprising at least one olefinic carbon-carbon-double bond in the presence of a thiocarbonylthio RAFT agent thereby forming a polymer comprising a terminal thiocarbonylthio group, and B2) cleaving the terminal thiocarbonylthio group to a thiol group thereby attaining the terminal thiol functionality of the polymer, and C) reacting the polymer with the rubber by a radical thiol-ene reaction thereby forming a grafted rubber, the grafted rubber comprising a backbone derived from the rubber and sidechains derived from the polymer. The polymer in a further step B3) is treated with a reducing agent before being used in the grafting reaction of step C).
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(2020/01/24)
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- Amphiphilic Bottlebrush Block Copolymers: Analysis of Aqueous Self-Assembly by Small-Angle Neutron Scattering and Surface Tension Measurements
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A systematic series of 16 amphiphilic bottlebrush block copolymers (BCPs) containing polystyrene and poly(N-acryloylmorpholine) (PACMO) side chains were prepared by a combination of atom-transfer radical polymerization (ATRP), photoiniferter polymerization, and ring-opening metathesis polymerization (ROMP). The grafting-through method used to prepare the polymers enabled a high degree of control over backbone and side-chain molar masses for each block. Surface tension measurements on the self-assembled amphiphilic bottlebrush BCPs in water revealed an ultralow critical micelle concentration (cmc), 1-2 orders of magnitude lower than linear BCP analogues on a molar basis, even for micelles with >90% PACMO content. Combined with coarse-grained molecular dynamics simulations, fitting of small-angle neutron scattering traces (SANS) allowed us to evaluate solution conformations for individual bottlebrush BCPs and micellar nanostructures for self-assembled macromolecules. Bottlebrush BCPs showed an increase in anisotropy with increasing PACMO content in toluene-d8, which is a good solvent for both blocks, reflecting an extended conformation for the PACMO block. SANS traces of bottlebrush BCPs assembled into micelles in D2O, a selective solvent for PACMO, were fitted to a core-shell-shell model, suggesting the presence of a partially hydrated inner shell. Results showed an average micelle diameter of 40 nm with combined shell diameters ranging from 16 to 18 nm. A general trend of increased stability of micelles (i.e., resistance to precipitation) was observed with increases in PACMO content. These results demonstrate the stability of bottlebrush polymer micelles, which self-assemble to form spherical micelles with ultralow (70 nmol/L) cmc's across a broad range of compositions.
- Alaboalirat, Mohammed,Qi, Luqing,Arrington, Kyle J.,Qian, Shuo,Keum, Jong K.,Mei, Hao,Littrell, Kenneth C.,Sumpter, Bobby G.,Carrillo, Jan-Michael Y.,Verduzco, Rafael,Matson, John B.
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p. 465 - 476
(2019/01/14)
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- Mannose-based graft polyesters with tunable binding affinity to concanavalin A
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Glycopolymers have been widely used to understand the interactions between carbohydrates and lectins, which facilitate the diagnosis and detection of disease and pathogens as well as the development of vaccines. While studies have been focused on the correlation of glycopolymer structure and their binding to lectins, graft-type glycopolyesters are uncommon. Herein, we report the design and synthesis of mannose-based graft polyesters by “grafting-from” method and investigate their interactions with Concanavalin A (Con A). As confirmed by 1H NMR spectroscopy and sulfuric acid-UV method, graft polyesters with different lengths of mannose graft were successfully synthesized. Our results from turbidimetry binding assay showed that graft polyesters with longer mannose graft exhibit higher initial binding rate (ki). Isothermal titration calorimetry measurements of these graft polyesters with Con A showed that polymers exhibit higher binding affinity (ka) with the number of side chain mannose. This study provides understanding of the interaction between Con A and mannose-based graft polyesters, which can be employed for the development of glycopolymeric therapeutics.
- Xie, Yixuan,Peng, Chao,Gao, Yunyi,Liu, Xiaohong,Liu, Tianbo,Joy, Abraham
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p. 3908 - 3917
(2017/10/07)
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- Synthesis of recyclable, chemically cross-linked, high toughness, high conductivity ion gels by sequential triblock copolymer self-assembly and disulfide bond cross-linking
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In this article, we report the synthesis of a disulfide bonded reversibly chemically cross-linked ion gel with high toughness and conductivity by sequential triblock copolymer self-assembly and the subsequent oxidation of thiol groups. Through reversible thiol-disulfide exchange, the ion gels had both high toughness of chemicals and recyclability of physical cross-linked ion gels. The triblock copolymer (SOS-SH) was prepared as follows: first, the RAFT copolymerization of styrene and 4-vinylbenzyl chloride (VBC) using CTA-PEO-CTA as a bi-functional macroRAFT agent was performed to obtain a triblock copolymer (SOS-Cl); then, the chloride group of SOS-Cl was replaced by an azido group to obtain SOS-N3; and finally, the click reaction of SOS-N3 with O-ethyl-S-prop-2-ynyl carbonodithioate and subsequent aminolysis were conducted to obtain SOS-SH. The disulfide bonded reversibly chemically cross-linked ion gel could be re-dissolved when mixed with a little amount of mild reducing agent (e.g., DTT) in CH2Cl2 with vigorous stirring, which reformed again after the removal of solvent and oxidation of thiol groups. The ion gels could undergo the reduction-oxidation cycle at least twice with a little loss of ionic conductivity and toughness (less than 25%), exhibiting good recyclability. Raman measurements were performed to confirm the existence and the key role of disulfide bond on the recyclability. This journal is
- Wei, Chengsha,Chen, Mingming,Liu, Dong,Zhou, Weiming,Khan, Majid,Wu, Xibo,Huang, Ningdong,Li, Liangbin
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p. 22638 - 22646
(2015/03/14)
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- Highly protein-resistant coatings and suspension cell culture thereon from amphiphilic block copolymers prepared by RAFT polymerization
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Novel amphiphilic block copolymers composed of hydrophobic (poly(2-methoxyethyl acrylate): M) and hydrophilic (poly(N,N-dimethylacrylamide) : D) segments were synthesized by living radical polymerization: a reversible addition-fragmentation chain-transfer polymerization. Two types of amphiphilic block copolymers, triblock (MDM) and 4-arm block ((MD)4) copolymers with specific compositions (D/M = (750-1500)/250), were prepared by a versatile one-pot synthesis. These copolymers show good adhesion to various types of substrates (e.g., polystyrene, polycarbonate, polypropylene, Ti, and glass), and the surface coating showed high protein repellency and a low contact angle for water, regardless of the substrate. The two opposing characteristics of high protein repellency and good substrate adhesion were achieved by the combined effects of the molecular architecture of the block copolymers, the high molecular weight, and the characteristics of each segment, that is, low protein adsorption capability of both segments and low glass transition temperature of the hydrophobic segment. Further, a polystyrene dish coated with the MDM block copolymer could be sterilized by γ-ray irradiation and used as a good substrate for a suspension cell culture that exhibits low cell adhesion and good cell growth.
- Haraguchi, Kazutoshi,Kubota, Kazuomi,Takada, Tetsuo,Mahara, Saori
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p. 1992 - 2003
(2014/06/24)
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- Dual stimuli-responsive poly(N-isopropylacrylamide)- B -poly(l -histidine) chimeric materials for the controlled delivery of doxorubicin into liver carcinoma
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A series of dual stimuli responsive synthetic polymer bioconjugate chimeric materials, poly(N-isopropylacrylamide)55-block-poly(l-histidine) n [p(NIPAM)55-b-p(His)n] (n = 50, 75, 100, 125), have been synthesized
- Johnson, Renjith P.,Jeong, Young-Il,John, Johnson V.,Chung, Chung-Wook,Kang, Dae Hwan,Selvaraj, Manickam,Suh, Hongsuk,Kim, Il
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p. 1434 - 1443
(2013/07/19)
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- Thermoresponsive injectable hydrogel for three-dimensional cell culture: Chondroitin sulfate bioconjugated with poly(N-isopropylacrylamide) synthesized by RAFT polymerization
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A major challenge in in vitro cell delivery is to provide an optimum environment that mimics natural conditions to maintain correct cellular functions. To address this challenge, we present a biohybrid injectable hydrogel based on chondroitin sulfate (ChS) and poly(N-isopropylacrylamide) (PNIPAAm). PNIPAAm was synthesized at various molecular weights between 5 to 20 kDa by RAFT polymerization in the presence of S-1-dodecyl-S'-(α, α′- dimethyl-α″-acetic acid) trithiocarbonate as a chain transfer agent. The molecular weight range suitable for renal clearance was an important factor in the experimental design. The phase transition behavior and the gelation time of the hydrogel were measured to evaluate its possibility for further clinical application. Furthermore, hydrogel degradation was also a concern for clinical application. Samples were incubated in PBS with 100 U/ml of hyaluronidase at 37°C to determine their degradation behaviors and the results revealed that the hydrogel was biodegradable in physiological conditions. To evaluate the biocompatibility for potential use of the hydrogel as a cell delivery vehicle, in vitro two-dimensional (2-D) and three-dimensional (3-D) cell cultures were performed. Cells demonstrated excellent viability when cultured with the hydrogel. In addition, the arrangement of multiple cell layers in the hydrogel was achieved. These results indicate the thermoresponsive injectable hydrogel may be expected to have wide potential applications as a vehicle for the delivery of therapeutic cells.
- Lue, Shaoyu,Li, Bo,Ni, Boli,Sun, Zhihong,Liu, Mingzhu,Wang, Qin
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experimental part
p. 10763 - 10772
(2012/05/19)
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- Facile one pot synthesis of a range of reversible addition-fragmentation chain transfer (RAFT) agents
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The application of a universal synthetic strategy for the high yielding and facile synthesis of a wide range of functional RAFT agents including trithiocarbonates, xanthates and dithiocarbamates is described. The Royal Society of Chemistry.
- Skey, Jared,O'Reilly, Rachel K.
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supporting information; experimental part
p. 4183 - 4185
(2009/03/11)
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- Shell-crosslinked nanostructures from amphiphilic AB and ABA block copolymers of styrene-alt-(maleic anhydride) and styrene: Polymerization, assembly and stabilization in one pot
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Shell-crosslinked nanostructures having unusual rosette morphologies have been produced by a simple process from styrene and maleic anhydride. The Royal Society of Chemistry 2005.
- Harrisson, Simon,Wooley, Karen L.
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p. 3259 - 3261
(2007/10/03)
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- S-(alpha, alpha'-disubstituted-alpha"-acetic acid) substituted dithiocarbonate derivatives for controlled radical polymerizations, process and polymers made therefrom
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Dithiocarbonate derivatives are disclosed, along with a process for preparing the same. The dithiocarbonate compounds can be utilized as initators, chain transfer agents and/or terminators in controlled free radical polymerizations. The dithiocarbonates can be used to produce polymers having narrow molecular weight distribution. Advantageously, the compounds of the present invention can also introduce functional groups into the resulting polymers. The dithiocarbonate compounds have low odor and are substantially colorless.
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