Deep hydration: Poly(ethylene glycol) Mw 2000–8000 Da probed by vibrational spectrometry and small-angle neutron scattering and assignment of ΔG° to individual water layers

Rubinson, Kenneth A.; Meuse, Curtis W.

doi:10.1016/j.polymer.2012.11.016

Cited by 13 publications

(10 citation statements)

References 73 publications

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“…To this aim, the viscosity values of PEG solutions at 25 °C and at the concentrations of 5.8, 12.3, 19.2 and 29.5% w / v were determined by an AR 2000 rheometer (TA Instruments, Milan, Italy). The values of viscosity for PEG solutions within the concentration range of 5.8–29.5% w / v were calculated by linear interpolation (R 2 = 0.9945, see Figure S3, Supplementary Materials ) and resulted in good agreement with the values reported in the literature [ 46 , 47 ]. Table 3 reports the values of viscosity of PEG solutions used for the evaluation of average hydrodynamic radius of PNIPAM microgels as a function of applied osmotic pressure by DLS analysis.…”

Section: Methodssupporting

confidence: 73%

Microgel Particles with Distinct Morphologies and Common Chemical Compositions: A Unified Description of the Responsivity to Temperature and Osmotic Stress

Ruscito

Chiessi

Toumia

et al. 2020

Gels

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Poly(N-isopropylacrylamide) (PNIPAM) hydrogel microparticles with different core–shell morphologies have been designed, while maintaining an unvaried chemical composition: a morphology with (i) an un-crosslinked core with a crosslinked shell of PNIPAM chains and (ii) PNIPAM chains crosslinked to form the core with a shell consisting of tethered un-crosslinked PNIPAM chains to the core. Both morphologies with two different degrees of crosslinking have been assessed by confocal microscopy and tested with respect to their temperature responsivity and deformation by applying an osmotic stress. The thermal and mechanical behavior of these architectures have been framed within a Flory–Rehner modified model in order to describe the microgel volume shrinking occurring as response to a temperature increase or an osmotic perturbation. This study provides a background for assessing to what extent the mechanical features of the microgel particle surface affect the interactions occurring at the interface of a microgel particle with a cell, in addition to the already know ligand/receptor interaction. These results have direct implications in triggering a limited phagocytosis of microdevices designed as injectable drug delivery systems.

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Section: Methodssupporting

confidence: 73%

Microgel Particles with Distinct Morphologies and Common Chemical Compositions: A Unified Description of the Responsivity to Temperature and Osmotic Stress

Ruscito

Chiessi

Toumia

et al. 2020

Gels

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“…Interestingly, for higher PEG concentrations in water, chain interactions are dominated by hydration forces, and the formation of flexible plates one molecule in thickness has been suggested. 91 Adsorption is associated with additional interactions due to the double-layer electric field and wetting forces that can influence polymer assembly on the Cl − -covered Cu surface. In principle, this can include configurations that deviate substantially from the helical conformation that, among other variants, could include arrangements where the polar ether and nonpolar alkyl groups are biased to opposite sides of the molecule, whereby the amphiphilic character is expressed and stabilized by the metal− electrolyte interface.…”

Section: ■ Results and Discussionmentioning

confidence: 99%

“…Defects and variations in the water-stabilized helical conformations are conferred by ±G rotation about the C–C bond, while deviations from the T conformation about the C–O axis provide important structural flexibility. Interestingly, for higher PEG concentrations in water, chain interactions are dominated by hydration forces, and the formation of flexible plates one molecule in thickness has been suggested . Adsorption is associated with additional interactions due to the double-layer electric field and wetting forces that can influence polymer assembly on the Cl – -covered Cu surface.…”

Section: Resultsmentioning

confidence: 99%

SEIRAS Study of Chloride-Mediated Polyether Adsorption on Cu

et al. 2018

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Surface-enhanced infrared absorption spectroscopy is used to examine the co-adsorption of a selection of polyethers with Cl– under conditions relevant to superconformal Cu electrodeposition in CuSO4–H2SO4 electrolytes. In 0.1 mol/L H2SO4, a potential-dependent mixed SO4 2––H3O+/H2O layer forms on weakly textured (111) Cu thin-film surfaces. With the addition of 1 mmol/L NaCl, the SO4 2––H3O+/H2O adlayer is displaced and rapidly replaced by an ordered halide layer that disrupts the adjacent solvent network, leading to an increase in non-hydrogen-bonded water that makes the interface more hydrophobic. The altered wetting behavior facilitates co-adsorption of polyethers, such as poly(ethylene glycols), polyoxamers, or polyoxamines. Interfacial water is displaced by co-adsorption of the hydrophobic polymer segments on the Cl–-terminated surface, while the hydrophilic ether oxygens are available for hydrogen bond formation with the solvent. The combined polyether–Cl– layer serves as an effective suppressor of the Cu electrodeposition reaction by limiting access of Cuaq 2+ to the underlying metal surface. This insight differs from previous work which suggested that polymer adsorption is mediated by Cu+–ether binding.

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“…The low intensity of these new bands is associated with the polymer molecular weight (Mw). As the polymers Mw increases, the bands associated with the vibrational modes of OH and C—OH decreases in intensity [25]. After the PEG 2000 esterification, it is possible to note a short decrease of O—H stretching intensity (See Supplementary Material—Figure S1).…”

Section: Resultsmentioning

confidence: 99%

“…Herein, we report a post-polymerization modification of poly(ethylene glycol) (PEG) functionalized with a (l-(β-Carboxyethyl)-3′,3′-dimethyl-6-nitrospiro(indoline-2′,2[2 H -1] benzopyran) (SPCOOH) by Steglich [25] esterification (PEGSP2) and the preparation of photochromic ES nanofibers based on the polymer blend containing poly(ε-caprolactone) (PCL) and PEGSP2. This photochromic polymer was characterized by Fourier transform infrared spectroscopy with attenuated total reflectance (FTIR-ATR), nuclear magnetic resonance (NMR), ultraviolet-visible spectroscopy (UV-Vis), thermal gravimetric analysis (TGA/DTG) and differential scanning calorimetry (DSC).…”

Section: Introductionmentioning

confidence: 99%

Nanostructured and Photochromic Material for Environmental Detection of Metal Ions

2019

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Compared to conventional spectroscopy or chromatography analysis, chemical sensing based on colorimetric changes offers an alternative to monitor potential metal hazards in aqueous environment through rapid and low-cost colorimetric changes which can be easily interpreted. In this work poly(ethylene glycol) (PEG 2000) was modified with a carboxylic acid spiropyran (SPCOOH) derivate by Steglich esterification (PEGSP2). PEGSP2 was incorporated into a poly(ε-caprolactone) (PCL) polymer matrix by electrospinning technique to produce nanofibers with photochromic properties. Spectroscopic analysis, thermal gravimetric analysis (TGA), and differential scanning calorimetry (DSC) were used to characterize PEGSP2. Drop shape analysis (DSA) and scanning electronic microscopy (SEM) were used to characterize the electrospun (ES) nanofibers morphology. Several metal ions solutions relevant to environmental hazards were prepared to be spotted on the surface of ES nanofibers for photochromatic sensing. Among them, Mg2+, Ca2+, Zn2+, Cd2+, La3+, and Er3+ demonstrated orange fluorescence when exposed to UV light. ES nanofibers also presented higher wettability when compared to a pure PCL polymer matrix, which is critical for sensitivity. Eighteen metals ions could be detected on the electrospun material. Additionally, among all metal ions Fe3+ was the most sensitive one in solution, in a µmol L−1 range.

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Deep hydration: Poly(ethylene glycol) Mw 2000–8000 Da probed by vibrational spectrometry and small-angle neutron scattering and assignment of ΔG° to individual water layers

Cited by 13 publications

References 73 publications

Microgel Particles with Distinct Morphologies and Common Chemical Compositions: A Unified Description of the Responsivity to Temperature and Osmotic Stress

Microgel Particles with Distinct Morphologies and Common Chemical Compositions: A Unified Description of the Responsivity to Temperature and Osmotic Stress

SEIRAS Study of Chloride-Mediated Polyether Adsorption on Cu

Nanostructured and Photochromic Material for Environmental Detection of Metal Ions

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