RSC Advances
·
2018
·Vol. 8
·期 56
·32193-32199
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IF 2.936
Yiyuan Tang,Kai Chen,Jiacheng Li,Yuhong Feng,Gaobo Yu,Longzheng Wang,Xinyu Zhao,Yang Peng,Quan Zhang
In this study, a pH-responsive amphiphilic alginate (Ugi-Alg) was synthesized via Ugi reaction without using a catalyst. The structure of Ugi-Alg was confirmed by FT-IR and 1H NMR spectroscopy. Amphiphilic alginate can form micelles in an aqueous medium due to it's amphiphilic nature.. The impacts of Na+ concentration and pH on the micelle size were characterized by dynamic light scattering (DLS) and transmission electron microscopy (TEM). The dynamic light scattering observations showed that micelle size increases with the decrease in Na+ concentration in aqueous solution. However, the micelle size decreases first and then increases as the pH value decreases from 5.3 to 2.0. Transmission electron microscopy confirmed that the mean size of micelles is 30–200 nm. In addition, a model hydrophobic pesticide (acetamiprid) was loaded in the micelles. The encapsulation efficiency and release behavior of micelles were studied, which could be controlled by Na+ concentration and pH. The results indicated that encapsulation efficiency of acetamiprid increases from 55% to 96% due to the increase in Na+ concentration from 0.01 M to 0.3 M. Moreover, with the decrease in pH from 5.3 to 2.0, encapsulation efficiency increases from 55% to 80%. Furthermore, the data of acetamiprid release kinetics could be well-fitted by the Weibull model.
研究领域:
材料科学
·
环境科学
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产品关联
DOI
PubMed
高影响因子
CARBOHYDRATE POLYMERS
·
2015
·
IF 4.074
Huiqiong Yan,Xiuqiong Chen,Jiacheng Li,Yuhong Feng,Zaifeng Shi,Xianghui Wang,Qiang Lin
In this research, the systematic evaluation of fundamental properties of the alginate derivative (Ugi-Alg) synthesized by the Ugi reaction is presented. The structure of Ugi-Alg with the degree of substitution of 23.24% was confirmed by FT-IR and 1 H NMR spectrometers. The X-ray diffraction (XRD) results indicate the amorphous structure and the crystal structure change of Ugi-Alg, which is possibly ascribed to the destruction of inter- and intra-molecular hydrogen bonding interactions during the Ugi reaction. From thermal gravimetric analysis (TGA) and fluorescence spectrophotometer, Ugi-Alg shows high thermal stability and good amphiphilic functionality with the critical aggregation concentration of 0.07 g/L in 0.15 mol/L aqueous NaCl solution. Transmission electron microscope (TEM) image and dynamic light scattering (DLS) reveal that stable Ugi-Alg self-aggregated micelle with the average size of 162.3 nm and ζ potential at about −31.7 mV could form in the aqueous media, which presents tremendous potential in pharmacology and tissue engineering.
研究领域:
材料科学
·
药学
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DOI
高影响因子
POLYMER BULLETIN
·
2021
·Vol. 79
·期 9
·7809-7826
·
IF 2.87
Liu Zhaowen,Chen Xiuqiong,Wen Yanshi,Bao Chaoling,Liu Chunyang,Cao Shirui,Yan Huiqiong,Lin Qiang
To improve the affinity of alginate to the hydrophobic drug molecules, such as ibuprofen, the Ugi four-component condensation reaction involving sodium alginate (SA), tosylmethyl isocyanide, propionaldehyde and octylamine was proposed to synthesize the novel amphiphilic alginate-bisamide derivative (AABD) without any organic solvents and catalysts. The molecular structure and self-aggregate behavior of the resultant AABD was characterized by FT-IR spectrometer, 1 H NMR spectrometer, X-ray diffraction, thermal gravimetric analysis, fluorescence spectrophotometer, transmission electron microscope and dynamic light scattering. Meanwhile, the loading and in vitro release of ibuprofen for the AABD microcapsules prepared by the emulsification method as well as their cytotoxicity were also investigated. Experimental results showed that the AABD with the degree of substitution of 19.41% was successfully prepared by the Ugi reaction, and the grafting of hydrophobic side groups on the backbone of alginate was conducive to enhancing its molecular flexibility and colloidal interface activity. Therefore, the AABD could reveal good amphiphilic property with the critical aggregation concentration (CAC) of 0.105 g/L in 0.15 mol/L aqueous NaCl solution, and form the self-aggregated micelle with the average hydrodynamic diameter of 396 nm (PDI = 0.31) and zeta potential at about − 62.4 mV. Furthermore, the prepared AABD microcapsules displayed the high encapsulation efficiency and sustained-release property in comparison with the SA microcapsules for the good affinity of AABD to hydrophobic ibuprofen that retarded the drug diffusion. And it also exhibited low cytotoxicity to the murine macrophage RAW264.7 cells. Therefore, the novel amphiphilic AABD synthesized by the Ugi reaction would be of great potentials as the hydrophobic drug carriers for sustained-release formulations.
研究领域:
材料科学
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药物递送
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生物医学工程
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产品关联
DOI
高影响因子
JOURNAL OF POLYMER RESEARCH
·
2020
·Vol. 27
·期 8
·1-11
·
IF 2.426
Fu Congcong,Ding Lan,Yin Jialin,Tian Shasha,Ma Lan,Zhang Qi,Qin Fei,Cao Lili,Deng Kuilin
In this investigation, we described a facile preparation of temperature/photo dual sensitive polymers (PGABs) by Ugi four-component polymerization (Ugi-4CP) at room temperature in “one-pot” method using glutaraldehyde, 4 -amido-azobenzene, t -butyl isocyanide and carboxyl-end-capped polyethylene glycols (S-PEG) as monomers. PGABs were found to be reversibly sensitive to the temperature in salt solution, and their lower critical solution temperatures (LCST) can be tuned to the range of 17.2–68.4 °C by changing the structure of PGABs, sort and concentration of salt. The configuration transition of PGABs between cis -form and trans -form was reversibly induced by the alternating radiation at 365 and 254 nm. The rate and conversion of isomerization showed a remarkable dependence on the chemical structure of PGAB. By the photosensitivity, the LCST of PGAB-800 is further regulated in 1.0 °C change because of the hydrophilicity difference of cis - trans -azobenzene moiety. Through the combination of the thermosensitivity and photosensitivity, the particles of PGABs with nano/μm dimension were successfully controlled by the light radiation and temperature change.
研究领域:
高分子化学
·
材料科学
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产品关联
DOI
高影响因子
Materials Science & Engineering C-Materials for Biological Applications
·
2020
·
IF 5.88
Hongye Huang,Ruming Jiang,Haijun Ma,Yongsan Li,Yuan Zeng,Naigen Zhou,Liangji Liu,Xiaoyong Zhang,Yen Wei
Multicomponent reactions (MCRs) have attracted broad interest for preparation of functional nanomaterials especially for the synthesis of functional polymers. Herein, we utilized an “old” MCR, the four-component Ugi reaction, to synthesize disulfide bond containing poly(PEG-TPE-DTDPA) amphiphilic copolymers with aggregation-induced emission (AIE) feature. This four-component Ugi reaction was carried out under rather mild reaction conditions, such as room temperature, no gas protection and absent of catalysts. The amphiphilic poly(PEG-TPE-DTDPA) copolymers with high number-average molecular weight (up to 86,440 Da) can self-assemble into claviform fluorescent polymeric nanoparticles (FPNs) in aqueous solution, and these water-dispersed nanoparticles exhibited strong emission, large Stokes shift (142 nm), low toxicity and remarkable ability in cellular imaging. Moreover, owing to the introduction of 3,3′-dithiodipropionic acid with disulfide bond, the resultant AIE-active poly(PEG-TPE-DTDPA) could display reduction-responsiveness and be utilized for synthesis of photothermal agents in-situ. Therefore, the AIE-active poly(PEG-TPE-DTDPA) could be promising for controlled intracellular delivery of biological activity molecules and fabrication of multifunctional AIE-active materials. Therefore, these novel AIE-active polymeric nanoparticles could be of great potential for various biomedical applications, such as biological imaging, stimuli-responsive drug delivery and theranostic applications.
研究领域:
材料科学
·
生物医学工程
·
化学合成
✓ 已验证
产品关联
DOI
PubMed
高影响因子
ACS Applied Polymer Materials
·
2024
·
IF 4.4
Yunfei Liu,Yayu Feng,Yue Sun,Meijing Zhang,Pengfei Zhang,Ronghui Zhao,Kuilin Deng
In this investigation, a nonconjugated fluorescent polyamide with piperazine and valerolactam moieties (PAM–PV) has been synthesized by the modified Ugi polymerization using 1,4-bis(3-aminopropyl)piperazine, levulinic acid, and 1,4-bis(3-isocyanopropyl)piperazine as monomers. In the polymerization, the special construction of levulinic acid leads to the formation of valerolactam on PAM–PV chains via the Mumm rearrangement. PAM–PV shows a strong fluorescence emission at 428 nm due to the intramolecular aggregation of piperazine and valerolactam moieties along the backbone. Impressively, PAM–PV can specifically detect NO2– ions via static quenching with a linear range of 10–6–10–5 M and a detection limit of 0.6 μM (0.0276 mg/L), which was far less than the minimum allowable concentration of 3 mg/L for NO2– in drinking water specified by WHO. Furthermore, the several common anions and cations have no interference effects on the specific detection of PAM–PV to NO2– ions. The quenching mechanism of NO2– and PAM–PV by FTIR, UV, and 1H NMR measurements indicates that the strong electrostatic interaction between NO2– and PAM–PV makes the macromolecular chains more relaxed and outstretched, leading to a formation of a nonfluorescent complex. Moreover, the practical detection of NO2– in the three water bodies, sauerkraut, and ham sausage and the fabrication of a portable detecting paper to NO2– ions were conducted in this experiment.
研究领域:
聚合物化学
·
分析化学
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环境科学
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产品关联
DOI
高影响因子
危险品化学品经营许可证（带存储）