| Reference | [1]. J Nanosci Nanotechnol. 2010 Sep;10(9):5557-69. doi: 10.1166/jnn.2010.2498.<br />
Study of polymeric interactions of copolymers: 2-hydroxyethyl methacrylate (HEMA) and 2,3-dihydroxypropyl methacrylate (DHPMA) with copper hydroxylated nanoballs.<br />
McCann K(1), Knudsen B, Ananthoji R, Perry JJ, Hilker B, Zaworotko MJ, Harmon JP.<br />
Author information: (1)University of South Florida, 4202 E Fowler Avenue, Tampa, FL 33620, USA.<br />
2-hydroxyethyl methacrylate (HEMA) and 2,3-dihydroxypropyl methacrylate (DHPMA) were used to synthesize novel nanocomposites containing 0.5% by weight of copper hydroxylated nanoballs. Glass transition temperatures of the copolymers and their respective nanocomposites were determined by using differential scanning calorimetry (DSC). Thermogravimetric analysis (TGA) was employed to measure the degradation temperatures of the samples and to determine if the degradation is a single step process or multiple step process. The dielectric permittivity (epsilon') and loss factor (epsilon") were measured via Dielectric Analysis (DEA) in the frequency range 0.1 Hz to 100 kHz and between the temperature -150 to 190 degrees C. gamma, beta, and alphabeta conductivity relaxations were revealed using the electric modulus formalism. The activation energies for the relaxations were calculated. Argand plots of M" versus M' were used to study the viscoelastic effects of both copolymer and the composites. Herein we show that it is possible to tune solubility and relaxation properties which are important to the design of new biomaterials.<br />
DOI: 10.1166/jnn.2010.2498 PMID: 21133074<br />
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[2]. Langmuir. 2010 Apr 20;26(8):5507-19. doi: 10.1021/la903748z.<br />
Adsorbed and spread films of amphiphilic triblock copolymers based on poly(2,3-dihydroxypropyl methacrylate) and poly(propylene oxide) at the air-water interface.<br />
Amado E(1), Blume A, Kressler J.<br />
Author information: (1)Martin Luther University Halle-Wittenberg, Institute of Chemistry-Physical Chemistry, D-06099 Halle (Saale), Germany.<br />
The adsorption behavior of the novel type of water-soluble amphiphilic triblock copolymers PGMA-b-PPO-b-PGMA at the air-water interface is studied by tensiometry and monolayer techniques. In particular, (PGMA(14))(2)-PPO(34) is found to be strongly surface active (Pi(max) approximately 38.1 mN/m, cmc approximately 50 microM), in spite of having a relatively short hydrophobic PPO middle block. Time-dependent adsorption measurements exhibit two different types of adsorption kinetics depending on concentration. Monolayers deposited by spreading form pseudo-Langmuir films, in spite of (PGMA(14))(2)-PPO(34) high water solubility. The transition from a dilute to a semidilute regime during compression of the monolayer occurs at a mean molecular area around 4424 A(2)/molecule (Pi = 0.03 mN/m). Above Pi = 2.1 mN/m (1291 A(2)/molecule) PGMA segments begin to change from a flat two-dimensional conformation to loops and tails protruding into the subphase. The onset of the conformational change for PO segments takes place at a mean molecular area of approximately 625 A(2)/molecule (Pi = 15.5 mN/m). In the range Pi approximately 21.4-23.8 mN/m the PPO blocks adopt a three-dimensional conformation. A new methodology for the estimation of the amount of polymer absorbed at the interface (Gamma) as a function of the solution bulk concentration from tensiometry measurements in pseudo-Langmuir spread films is proposed. The obtained adsorption isotherm suggests the occurrence of a conformational change of the PPO block segments toward conformations having smaller molar areas for actual bulk concentrations above 6.0 x 10(-8) M. The surface tension versus polymer bulk concentration curve (gamma vs ln C) exhibits a sharp break at low concentrations, which is probably due to a conformational change within the adsorbed layer. A theoretical multiple conformation model reproduces satisfactorily the experimental dependency of surface pressure on polymer adsorption (Pi vs Gamma) at low and intermediate ranges of polymer concentrations in the solution bulk. A ratio of approximately eight between the average molecular areas at low coverage and at full coverage confirms that (PGMA(14))(2)-PPO(34) chains are highly flexible and able to adopt very different conformations during the transition of the adsorbed polymer film from a highly diluted to a nearly saturated state. There are some experimental indications that nonequilibrium effects might determine a bimodal conformational distribution within the adsorbed (PGMA(14))(2)-PPO(34) layer, which departs substantially from the equilibrium adsorption picture.<br />
DOI: 10.1021/la903748z PMID: 19950939<br />
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[3]. Anal Chem. 2003 Feb 15;75(4):1011-21. doi: 10.1021/ac026216w.<br />
Polar polymeric stationary phases for normal-phase HPLC based on monodisperse macroporous poly(2,3-dihydroxypropyl methacrylate-co-ethylene dimethacrylate) beads.<br />
Xu M(1), Peterson DS, Rohr T, Svec F, Fréchet JM.<br />
Author information: (1)Department of Chemistry, University of California, Berkeley, California 94720-1460, USA.<br />
The effect of variables such as shape template size, porogen composition and percentage, content of cross-linking monomer, and polymerization temperature on the properties of uniformly sized 3-microm porous poly(glycidyl methacrylate-co-ethylene dimethacrylate) beads prepared by the staged templated suspension polymerization technique has been studied. The porous properties of the beads including surface morphology, pore size distribution, and specific surface area have been optimized to obtain highly efficient stationary phases for normal-phase HPLC. A column packed with diol stationary phase obtained by hydrolysis of poly(glycidyl methacrylate-co-ethylene dimethacrylate) beads affords an efficiency of 67,000 plates/m for toluene using THF as the mobile phase. The retention properties and selectivity of the diol beads are easily modulated by changes in the composition of the mobile phase. The performance of these beads is demonstrated with the separations of a variety of polar compounds including positional isomers, aniline derivatives, and basic tricyclic antidepressant drugs.<br />
DOI: 10.1021/ac026216w PMID: 12622399<br />
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[4]. Biomacromolecules. 2016 Oct 10;17(10):3305-3317. doi: 10.1021/acs.biomac.6b01049. Epub 2016 Sep 27.<br />
Functionalization of Active Ester-Based Polymersomes for Enhanced Cell Uptake and Stimuli-Responsive Cargo Release.<br />
Scherer M(1), Kappel C(2), Mohr N(1), Fischer K(3), Heller P(1), Forst R(1), Depoix F(4), Bros M(2), Zentel R(1).<br />
Author information: (1)Institute of Organic Chemistry, Johannes Gutenberg-University Mainz , Duesbergweg 10-14, 55128 Mainz, Germany. (2)Department of Dermatology, University Medical Center, Johannes Gutenberg-University Mainz , Obere Zahlbacher Straße 63, 55131 Mainz, Germany. (3)Institute of Physical Chemistry, Johannes Gutenberg University Mainz , Jakob-Welder-Weg 11, 55099 Mainz, Germany. (4)Institute of Zoology, Johannes Gutenberg University Mainz , J.-J.-Becher-Weg 7, 55128 Mainz, Germany.<br />
Poly(2,3-dihydroxypropyl methacrylamide) (P(DHPMA))-based amphiphilic block copolymers have recently proven to form polymer vesicles (polymersomes). In this work, we further expand their potential by incorporating (i) units for pH-dependent disintegration into the hydrophobic membrane and (ii) mannose as targeting unit into the hydrophilic block. This last step relies on the use of an active ester prepolymer. We confirm the stability of the polymersomes against detergents like Triton X-100 and their low cytotoxicity. The incorporation of 2-(2,2-dimethyl-1,3-dioxolane-4-yl)ethyl methacrylate into the hydrophobic block (lauryl methacrylate) allows a pH-responsive disintegration for cargo release. Efficient decomposition of the polymersome structure is monitored by dynamic light scattering. It is thus possible to include an active enzyme (glucose oxidase), which gets only active (is set free) after vesicle disintegration. In addition, the introduction of mannose as targeting structure allows enhanced and selective targeting of dendritic cells.<br />
DOI: 10.1021/acs.biomac.6b01049 PMID: 27673444<br />
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[5]. J Chromatogr A. 2009 Oct 2;1216(40):6824-30. doi: 10.1016/j.chroma.2009.08.031. Epub 2009 Aug 18.<br />
High binding capacity surface grafted monolithic columns for cation exchange chromatography of proteins and peptides.<br />
Krenkova J(1), Gargano A, Lacher NA, Schneiderheinze JM, Svec F.<br />
Author information: (1)The Molecular Foundry, E. O. Lawrence Berkeley National Laboratory, Mailstop 67R6110, Berkeley, CA 94720, USA.<br />
Poly(glycidyl methacrylate-co-ethylene methacrylate) monoliths have been prepared in 100 microm i.d. capillaries and their epoxy groups hydrolyzed to obtain poly(2,3-dihydroxypropyl methacrylate-co-ethylene methacrylate) matrix. These polymers were then photografted in a single step with 2-acrylamido-2-methyl-1-propanesulfonic acid and acrylic acid to afford stationary phases for a strong and a weak cation exchange chromatography, respectively. Alternatively, poly(ethylene glycol) methacrylate was used for grafting in the first step in order to enhance hydrophilicity of the support followed by photografting with 2-acrylamido-2-methyl-1-propanesulfonic acid or acrylic acid in the second step. These new columns were used for the separation of proteins and peptides. A mixture of ovalbumin, alpha-chymotrypsinogen, cytochrome c, ribonuclease A and lysozyme was used to assess the chromatographic performance for large molecules while a cytochrome c digest served as a model mixture of peptides. All tested columns featured excellent mass transfer as demonstrated with very steep breakthrough curves. The highest binding capacities were found for columns prepared using the two step functionalization. Columns with sulfonic acid functionalities adsorbed up to 21.5 mg/mL lysozyme while the capacity of the weak cation exchange column functionalized with acrylic acid was 29.2 mg/mL.<br />
DOI: 10.1016/j.chroma.2009.08.031 PMID: 19717157
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