Investigation of the Hydration of Nonfouling Material Poly(ethylene glycol) by Low-Field Nuclear Magnetic Resonance

Langmuir ◽  
2012 ◽  
Vol 28 (4) ◽  
pp. 2137-2144 ◽  
Author(s):  
Jiang Wu ◽  
Shengfu Chen
Keyword(s):  
Nuclear Magnetic Resonance ◽  
Magnetic Resonance ◽  
Ethylene Glycol ◽  
Poly Ethylene Glycol ◽  
Low Field ◽  
Poly Ethylene ◽  
Nuclear Magnetic

13C/7Li Solid-State Nuclear Magnetic Resonance Study on Poly(Ethylene Glycol)-Poly(Propylene Glycol)-Poly(Ethylene Glycol)/LiCF3SO3 Copolymer Electrolytes

2020 ◽  
Vol 982 ◽  
pp. 26-33
Author(s):  
Ling Wei ◽  
Da Wei Li
Keyword(s):  
Nuclear Magnetic Resonance ◽  
Solid State ◽  
Magnetic Resonance ◽  
High Resolution ◽  
Ethylene Glycol ◽  
Phase Structure ◽  
Poly Ethylene Glycol ◽  
Chain Dynamics ◽  
Poly Ethylene ◽  
Nuclear Magnetic

Solid-state high-resolution 13C/7Li nuclear magnetic resonance (NMR) study was performed on the phase structure and chain dynamics of PEG-PPG-PEGn/LiCF3SO3 (n=3, 6, 12) copolymer electrolytes. PEG repeating units and Li+ form PEG3:LiCF3SO3 crystalline complex and PE3/Li+ amorphous complex in all the samples. PPG repeating units and Li+ form different complexes with respect to O:Li+ feed ratio (denoted as PP/Li+-3/6/12). The 13C chemical shifts and half widths of the signals from PP/Li+-3/6/12 remain unchanged, which implies the structures of PP/Li+-3/6/12 are similar at least in a very short range. The half width of the 7Li signals from PP/Li+-3/6/12 becomes narrower and narrower as the Li+ concentration decreases. This indicates the chain mobility of the amorphous phase increases with the decrease of ionic concentration. Moreover, neat crystalline PEG, neat amorphous PEG and neat amorphous PPG start to appear when O:Li+ is greater than 3:1 and their contents increase with the increase of O:Li+. Overall, solid-state high-resolution NMR is a powerful and unique method for understanding the phase structure and chain dynamics of solid polymer electrolytes (SPEs), more applications of this technique to studies on SPEs is expecting.

In vivo evaluation of biocompatibility and immune modulation potential of poly(caprolactone)–poly(ethylene glycol)–poly(caprolactone)-gelatin hydrogels enriched with nano-hydroxyapatite in the model of mouse

2021 ◽  
pp. 088532822199852
Author(s):  
Mahdieh Alipour ◽  
Javad Ashrafihelan ◽  
Roya Salehi ◽  
Zahra Aghazadeh ◽  
Aysa Rezabakhsh ◽  
...  
Keyword(s):  
Nuclear Magnetic Resonance ◽  
Magnetic Resonance ◽  
Ethylene Glycol ◽  
Poly Ethylene Glycol ◽  
Injectable Hydrogels ◽  
Lymphocyte Ratio ◽  
Cd4 Lymphocyte ◽  
Poly Ethylene ◽  
Poly Caprolactone

Biocompatible, biodegradable, and injectable hydrogels are a novel and promising approach for bone regeneration. In this study, poly(caprolactone)–poly(ethylene glycol)–poly(caprolactone) (PCL-PEG-PCL), PCL-PEG-PCL-gelatin (Gel), PCL-PEG-PCL-Gel/nano-hydroxyapatite (nHA) injectable hydrogels were synthesized and evaluated in a mouse model of subcutaneous transplantation after 14 days. PCL-PEG-PCL-Gel and PCL-PEG-PCL-Gel/nHA hydrogels were fabricated with in situ precipitation method. Structure, intermolecular interaction, and the reaction between the PCL-PEG-PCL, Gel, and nHA were evaluated using a scanning electron microscope (SEM), Fourier-transform infrared spectroscopy (FT-IR), proton nuclear magnetic resonance (H-NMR), and carbon nuclear magnetic resonance (C-NMR). Fourteen days after subcutaneous injection, the existence of an immune system reaction was investigated using Hematoxylin and Eosin (H&E) staining. Using immunofluorescence imaging, the number of CD68+ cells was determined in the periphery of the hydrogel. The CD8/CD4 lymphocyte ratio was also calculated in blood samples. We monitored the expression of CCL-2, BCL-2, IL-10, and CD31 using real-time PCR assay. The chemical evaluation revealed the successful integration of Gel and nHA to the PCL-PEG-PCL backbone. Histological examination showed the lack of inflammation at the site of injection. No toxicological effects were determined in hepatic and renal tissues. The addition of nHA to the PCL-PEG-PCL-Gel decreased biodegradation time. None of the hydrogels caused statistically significant differences in the number of CD68 cells (p > 0.05). The CD8/CD4 lymphocyte ratio remained unchanged in all groups (p > 0.05). Compared to the PCL-PEG-PCL group, the addition of nHA and Gel increased the expression of CCL-2, BCL-2, IL-10, and CD31 (p < 0.05). In conclusion, the current study showed that PCL-PEG-PCL-Gel/nHA hydrogels could be used in in vivo conditions without prominent toxic effects and inflammatory responses.

Dynamic Inhomogeneity in Homogeneous Polymer Melts

Soft Matter ◽  
2021 ◽  
Author(s):  
Lin-Lin Chu ◽  
Kaipin Xu ◽  
Robert Graf ◽  
Zhichao Yan ◽  
Junfang Li ◽  
...  
Keyword(s):  
Nuclear Magnetic Resonance ◽  
Magnetic Resonance ◽  
Ethylene Oxide ◽  
Polymer Melts ◽  
Double Quantum ◽  
Chain Entanglement ◽  
Poly Ethylene Oxide ◽  
Poly Ethylene ◽  
Nuclear Magnetic

Chain entanglement behaviors were studied by 1H Hahn echo nuclear magnetic resonance (NMR) and 1H double-quantum (DQ) NMR experiments. Poly(ethylene oxide) (PEO) was chosen to investigate the chain entanglement behaviors....

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