DESALINATION
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2019
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IF 6.035
Biaowen Wei,Jiancong Pan,Jun Feng,Caidi Chen,Shijun Liao,Yigang Yu,Xiuhua Li
A series of series-connected dication ionic ionomers with flexible hydrophobic tails (QPTs) designed for electrodialysis desalination (ED) anion exchange membranes have been synthesized successfully from a monoionic quaternization agent N -(2-(dimethylamino)ethyl)- N , N -dimethylhexan-1-aminium bromide and brominated poly(2,6-dimethyl-1,4-phenylene oxide). The properties of QPTs membranes were evaluated in terms of ion exchange capacity (IEC), water uptake (WU), swelling ratio (SR), thermal stability, membrane area resistance (R m ), permselectivity (P) and ED experiments. The results confirm that the coaction of the series-connected dications linking by a short chain of two methylene groups and the middle length aliphatic tails offers QPTs excellent conductivity and permselectivity simultaneously. Especially, QPT-4 membrane has an excellent permselectivity of 94.0% and the lowest R m of 1.60 Ω cm 2 at the highest IEC of 2.33 mmol g − 1 . Moreover, QPT-4 membrane shows the best ED performances with current efficiency of 89.14%, salt flux of 75.57 mg m − 2 s − 1 and energy consumption of 2.16 kWh kg − 1 in the mostly reported NaCl ED system, which are much higher than those of commercial TWEDA1 (the corresponding values of 83.96%, 71.19 mg m − 2 s − 1 and 2.67 kWh kg − 1 ). The excellent ED stability in the repeated tests further qualifies QPT-4 to be a very promising candidate for ED application.
研究领域:
材料科学
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环境工程
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产品关联
DOI
高影响因子
JOURNAL OF GEOPHYSICAL RESEARCH-ATMOSPHERES
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2023
·Vol. 128
·期 24
·e2023JD039971
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IF 4.4
Lanxiadi Chen,Soleil E. Worthy,Wenjun Gu,Allan K. Bertram,Mingjin Tang
Mineral dust is one of the most abundant types of ice nucleating particles in the atmosphere. During atmospheric transport, mineral dust particles can become coated with inorganic and organic solutes, which can impact their ice nucleation activity. Aminium cations formed from amines are one type of organic solute that can coat mineral dust particles in the atmosphere, but their effects on the ice nucleation activity of mineral dust have not been studied. We investigated the effects of primary, secondary, and tertiary aminium cations with methyl and ethyl groups, as well as ammonium cations, on the ice nucleation activity of K-feldspar, an important type of mineral dust, in the immersion freezing mode at low cation concentrations (0.2–20 mM) using a droplet-freezing apparatus. Ammonium cations substantially increased the ice nucleation activity of K-feldspar, consistent with previous studies. In contrast, primary aminium cations significantly reduced K-feldspar ice nucleation activity, and secondary and tertiary aminium cations had no significant effect (the effect was less than the uncertainty of our measurements). Our combined results are consistent with the following mechanisms: ammonium cations undergo ion exchange with K-feldspar, providing exposed N–H groups for hydrogen bonding with ice; primary aminium cations undergo ion exchange with K-feldspar, exposing a hydrophobic tail that is not effective at nucleating ice; secondary and tertiary aminium cations do not undergo ion exchange with K-feldspar due to steric effects caused by the multiple hydrophobic groups on the cation. Key Points Ammonium cations significantly increased the ice nucleation activity of K-feldspar Primary aminium cations substantially reduced the ice nucleation activity of K-feldspar Secondary and tertiary aminium had limited effects on the ice nucleation activity of K-feldspar due to their inability for ion exchange Plain Language Summary Ice nucleating particles are particles in the atmosphere that can initiate the formation of ice in liquid clouds, impacting cloud properties, precipitation, and climate. Mineral dust is a dominant type of ice nucleating particles in the atmosphere. During atmospheric transport, aminium cations, formed from amine gases which can be abundant in the atmosphere, can coat mineral dust particles altering their ability to nucleate ice. However, the effect of aminium cations on the ice nucleation ability of mineral dust particles has not been studied. We investigated the effects of aminium and ammonium cations on the ice nucleation ability of K-feldspar, an important type of mineral dust and ice nucleating particles in the atmosphere. Our results show that secondary and tertiary aminium cations have no effect on the ice nucleating ability of K-feldspar, but primary aminium cations greatly reduce the ice nucleating ability of K-feldspar. This has possible implications for predicting cloud formation in the atmosphere. We also present a mechanism related to ion exchange that can explain our ice nucleation results.
研究领域:
大气科学
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环境化学
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物理化学
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气候学
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产品关联
DOI
高影响因子
Journal of Materials Chemistry B
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2023
·Vol. 11
·期 10
·2095-2107
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IF 7
Yu Wei,Ting He,Qunjie Bi,Huan Yang,Xueyi Hu,Rongrong Jin,Hong Liang,Yongqun Zhu,Rongsheng Tong,Yu Nie
The success of mRNA vaccines for COVID-19 prevention raised global awareness of the importance of nucleic acid drugs. The approved systems for nucleic acid delivery were mainly formulations of different lipids, yielding lipid nanoparticles (LNPs) with complex internal structures. Due to the multiple components, the relationship between the structure of each component and the overall biological activity of LNPs is hard to study. However, ionizable lipids have been extensively explored. In contrast to former studies on the optimization of hydrophilic parts in single-component self-assemblies, we report in this study on structural alterations of the hydrophobic segment. We synthesize a library of amphiphilic cationic lipids by varying the lengths (C = 8–18), numbers (N = 2, 4), and unsaturation degrees (Ω = 0, 1) of hydrophobic tails. Notably, all self-assemblies with nucleic acid have significant differences in particle size, stability in serum, membrane fusion, and fluidity. Moreover, the novel mRNA/pDNA formulations are characterized by overall low cytotoxicity, efficient compaction, protection, and release of nucleic acids. We find that the length of hydrophobic tails dominates the formation and stability of the assembly. And at a certain length, the unsaturated hydrophobic tails enhance the membrane fusion and fluidity of assemblies and thus significantly affect the transgene expression, followed by the number of hydrophobic tails.
研究领域:
药学
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分子生物学
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纳米技术
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药物递送系统
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病毒学
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产品关联
DOI
PubMed
高影响因子
BIOORGANIC & MEDICINAL CHEMISTRY
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2025
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IF 3
Chao Liu,Yuhao Jiang,Wenliang Xue,Jinyu Liu,Zihao Wang,Xinsong Li
Lipid nanoparticles (LNP) are recognized as the most efficient non-viral carriers for the delivery of nucleic acids including small interfering RNA (siRNA) and messenger RNA (mRNA). Ionizable lipid within the system is pivotal component influencing encapsulation, endosomal escape, delivery efficiency and immunogenicity. Accordingly, the precision design of ionizable lipids is a key step in the development of LNP. In this report, we constructed sixteen Janus dendritic ionizable lipids by varying numbers and alkyl chain length of tails based on different ionizable head containing hydroxyl and tertiary amine groups. The corresponding LNP were prepared by using microfluidic mixing device, with all samples exhibiting particle size around 100 nm and polydispersity index (PDI) below 0.2. In vivo validation demonstrates that two optimized ionizable lipids containing two hydroxy groups, two tertiary amines and six hydrophobic chain tails (U-502, U-503) show superior delivery efficiency compared to lipids with less tails and commercial ALC-0315. Hematoxylin and Eosin (H&E) staining of tissues, immunogenicity, liver and kidney function tests additionally confirm that both ionizable lipids have favorable biocompatibility and low in vivo toxicity. Lysosomal escape and cell transfection data verify the in vitro delivery efficacy of these LNP. Taken together, Janus dendritic lipids with fine designed ionizable head and multiple hydrophobic tails have improved mRNA delivery efficiency and biosafety, which may be promise in the development of delivery system.
研究领域:
药剂学
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分子生物学
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纳米技术
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药物递送系统
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DOI
PubMed
高影响因子
INTERNATIONAL JOURNAL OF PHARMACEUTICS
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2024
·
IF 5.3
Chao Liu,Yuhao Jiang,Wenliang Xue,Jinyu Liu,Zihao Wang,Xinsong Li
Ionizable lipid-based lipid nanoparticles (LNP) play a crucial role in the delivery of mRNA. The hydrophobic tail of ionizable lipid affects the formation of LNP and the release of mRNA. In this report, we focus on the effect of the number, chain length, and double bond number of the hydrophobic tail on the delivery efficiency. First, a series of ionizable lipids with two, three and four tails were synthesized and characterized featured with imidazole group as the head. The ionizable lipids derived LNP were prepared using a microfluidic co-mixing device, yielding particles primarily in the size range of 100 to 150 nm, with a polydispersity index (PDI) below 0.2. Screening identified ionizable lipids with four tails exhibiting superior delivery efficiency, of which U-15, U-17, U-18 and U-19 demonstrated the highest performance. Additionally, the U-19 significantly prolongs mRNA expression duration, and along with specific extrahepatic delivery effect compared to ALC-0315. Tissue slice tests on representatives (U-06: two tails, U-19: four tails, U-29: three tails) revealed no notable abnormalities. Analysis of immunogenicity, liver and kidney function tests indicated that all samples exhibited no evident immunogenicity or in vivo toxicity. Findings from tests on lysosome escape, cell transfection, and cytotoxicity revealed excellent in vitro delivery effectiveness. In summary, among the 35 imidazole-based ionizable lipids screened, optimal effects were exhibited by four tails, which providing a new strategy for the development of ionizable lipids.
研究领域:
药学
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纳米技术
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分子生物学
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药物递送系统
✓ 已验证
DOI
PubMed
高影响因子