scholarly journals Amphiphilic Block Copolymers Bearing Hydrophobic γ-Tocopherol Groups with Labile Acetal Bond

Polymers ◽  
2019 ◽  
Vol 12 (1) ◽  
pp. 36
Author(s):  
Shotaro Yukioka ◽  
Takuya Kitadume ◽  
Suchismita Chatterjee ◽  
Gan Ning ◽  
Tooru Ooya ◽  
...  
Keyword(s):  
Diblock Copolymer ◽  
Main Chain ◽  
Polymer Micelles ◽  
Poly Ethylene Glycol ◽  
The Core ◽  
Anticancer Effects ◽  
Acidic Conditions ◽  
High Concentrations ◽  
Poly Ethylene ◽  
Hydrophobic Cores

High concentrations of γ-tocopherol (γTCP) tend to show antioxidant, anti-inflammatory, and anticancer effects. In this study, we prepared polymer micelles under acidic conditions with a controlled release of γTCP due to the decomposition of pendant acetal bonds. First, a precursor diblock copolymer composed of poly(ethylene glycol) (PEG) and acrylic acid (AA) was prepared. This was followed by the synthesis of an amphiphilic diblock copolymer (PEG54-P(AA/VE6/γTCP29)140), incorporated into hydrophobic γTCP pendant groups attached to the main chain through an acetal bond. The prepared PEG54-P(AA/VE6/γTCP29)140 was further dispersed in water to form polymer micelles composed of hydrophobic cores that were generated from a hydrophobic block containing γTCPs and hydrophilic shells on the surface. Under acidic conditions, γTCP was then released from the core of the polymer micelles due to the decomposition of the pendant acetal bonds. In addition, polymer micelles swelled under acidic conditions due to hydration of the core.

scholarly journals Effect of Molecular Architecture on Associating Behavior of Star-Like Amphiphilic Polymers Consisting of Plural Poly(ethylene oxide) and One Alkyl Chain

Polymers ◽  
2021 ◽  
Vol 13 (3) ◽  
pp. 460
Author(s):  
Daisuke Kugimoto ◽  
Aoi Taniguchi ◽  
Masaki Kinoshita ◽  
Isamu Akiba
Keyword(s):  
Ethylene Oxide ◽  
Average Molecular Weight ◽  
Amphiphilic Polymers ◽  
Hydrophobic Core ◽  
Molecular Architecture ◽  
Polymer Micelles ◽  
The Core ◽  
X Ray Scattering ◽  
Poly Ethylene Oxide ◽  
Poly Ethylene

Associating behavior of star-like amphiphilic polymers consisting of two or three poly(ethylene oxide) (PEO) chains and one stearyl chain (C18) was investigated. Although the aggregation number (Nagg) of linear analogue of amphiphilic polymers monotonically decreased with increasing number-average molecular weight of PEO (Mn,PEO), the Nagg of micelles of star-like amphiphilic polymers with Mn,PEO = 550 g/mol was smaller than that with Mn,PEO = 750 g/mol, whereas that with Mn,PEO ≥ 750 g/mol showed general Mn,PEO dependence. Small-angle X-ray scattering analyses revealed that the occupied area of one PEO chain on the interface between hydrophobic core and corona layer in the micelles of star-like polymers was much narrower than that in the linear amphiphilic polymers. This result indica ted the PEO chains of star-like polymers partially took unfavorable conformation near the core–corona interface in polymer micelles. The effect of local conformation of PEO chains near the interface on the associating behavior became significant as Mn,PEO decreased. Therefore, in polymer micelles of star-like amphiphilic polymers containing PEO with Mn,PEO = 550 g/mol, the enlargement of occupied area of PEO on the core–corona interface should be caused to avoid the formation of unfavorable conformations of partial PEO chains, resulting in a decrease in Naggs.

FhuA deletion variant Δ1-159 overexpression in inclusion bodies and refolding with Polyethylene-Poly(ethylene glycol) diblock copolymer

2011 ◽  
Vol 77 (1) ◽  
pp. 75-79 ◽  
Author(s):  
Tamara Dworeck ◽  
Anne-Kathrin Petri ◽  
Noor Muhammad ◽  
Marco Fioroni ◽  
Ulrich Schwaneberg
Keyword(s):  
Ethylene Glycol ◽  
Diblock Copolymer ◽  
Inclusion Bodies ◽  
Poly Ethylene Glycol ◽  
Deletion Variant ◽  
Poly Ethylene

scholarly journals Hybrid Mesoporous Silica Nanoparticles Grafted with 2-(tert-butylamino)ethyl Methacrylate-b-poly(ethylene Glycol) Methyl Ether Methacrylate Diblock Brushes as Drug Nanocarrier

Molecules ◽  
2020 ◽  
Vol 25 (1) ◽  
pp. 195 ◽  
Author(s):  
Abdullah M Alswieleh ◽  
Abeer M Beagan ◽  
Bayan M Alsheheri ◽  
Khalid M Alotaibi ◽  
Mansour D Alharthi ◽  
...  
Keyword(s):  
Mesoporous Silica ◽  
Ethylene Glycol ◽  
Silica Nanoparticles ◽  
Methyl Ether ◽  
Diblock Copolymer ◽  
Mesoporous Silica Nanoparticles ◽  
Poly Ethylene Glycol ◽  
Ethyl Methacrylate ◽  
Poly Ethylene ◽  
Glycol Methyl Ether

This paper introduces the synthesis of well-defined 2-(tert-butylamino)ethyl methacrylate-b-poly(ethylene glycol) methyl ether methacrylate diblock copolymer, which has been grafted onto mesoporous silica nanoparticles (PTBAEMA-b-PEGMEMA-MSNs) via atom transfer radical polymerization (ATRP). The ATRP initiators were first attached to the MSN surfaces, followed by the ATRP of 2-(tert-butylamino)ethyl methacrylate (PTBAEMA). CuBr2/bipy and ascorbic acid were employed as the catalyst and reducing agent, respectively, to grow a second polymer, poly(ethylene glycol) methyl ether methacrylate (PEGMEMA). The surface structures of these fabricated nanomaterials were then analyzed using Fourier Transform Infrared (FTIR) spectroscopy. The results of Thermogravimetric Analysis (TGA) show that ATRP could provide a high surface grafting density for polymers. Dynamic Light Scattering (DLS) was conducted to investigate the pH-responsive behavior of the diblock copolymer chains on the nanoparticle surface. In addition, multifunctional pH-sensitive PTBAEMA-b-PEGMEMA-MSNs were loaded with doxycycline (Doxy) to study their capacities and long-circulation time.

Water-soluble star polymers with a phthalocyanine as the core and poly(ethylene glycol) chains as branches

2012 ◽  
Vol 126 (4) ◽  
pp. 1359-1368 ◽  
Author(s):  
Placido Mineo ◽  
Rossana Alicata ◽  
Norberto Micali ◽  
Valentina Villari ◽  
Emilio Scamporrino
Keyword(s):  
Ethylene Glycol ◽  
Star Polymers ◽  
Water Soluble ◽  
Poly Ethylene Glycol ◽  
The Core ◽  
Poly Ethylene

Mesoscale Simulation of the Structure of Star Acrylated Poly(ethylene glycol-co-lactide) Hydrogels

2012 ◽  
Vol 1418 ◽  
Author(s):  
Seyed Sina Moeinzadeh ◽  
Esmaiel Jabbari
Keyword(s):  
Ethylene Glycol ◽  
Volume Fraction ◽  
Equations Of Motion ◽  
Dissipative Particle Dynamics ◽  
Random Force ◽  
Dynamics Simulation ◽  
Coarse Grained ◽  
Poly Ethylene Glycol ◽  
The Core ◽  
Poly Ethylene

ABSTRACTIn this work the microstructures of star acrylated poly(ethylene glycol-co-lactide) (SPELA) with different LA:EG ratios in the aqueous solution have been simulated via Dissipative Particle Dynamics (DPD) approach at the mesoscale. The system components were coarse-grained into different beads (set of atoms) which moved according to the Newton’s equations of motion integrated via a modified Velocity-Verlet algorithm. The force acting on each bead, in a specific cutoff distance (rc), was divided into a conservative force (FC), random force (FR), dissipative force (FD), bond force (FS) and bond angle force (FE). The repulsion parameters of the conservative force (αij) were calculated from the solubility parameter of the beads, each of which were extracted from an atomistic molecular dynamics simulation (MD). Simulations showed the formation of micelles with lactide and acrylate beads occupied the core and hydrophilic ethylene oxide segments extending through the water to form the corona. The micelles showed an increasing trend in size and decreasing trend in number density with increase in LA:EG ratio. Results showed that the acrylate density decreased from the center of the micelles to the core surface although the overall amount of acrylates increased due to the increase in volume. Furthermore, the running integration number of acrylate-water beads showed decreasing accessibility of acrylates to water with increasing PLA volume fraction.

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