ChemPlusChem
·
2020
·Vol. 85
·期 4
·679-683
·
IF 2.753
Shengke Li,Kit Ieng Kuok,Xia Ji,Anni Xu,Hang Yin,Jun Zheng,Huaping Tan,Ruibing Wang
Graphical Antibacterial switch : The capability of cucurbit[7]uril (CB[7]) in modulating the antibacterial activity of ambroxol hydrochloride (ABX) was successfully demonstrated by using two strains of Pseudomonas aeruginosa and Escherichia coli . The antibacterial activity of ABX was “turned off” upon encapsulation by CB[7] and “turned on” after ABX was released from the CB[7]-ABX host–guest complex upon addition of a competitive guest amantadine hydrochloride. Supramolecular encapsulation by cucurbit[7]uril (CB[7]) was recently demonstrated to provide a simple and efficient method for antibacterial activity regulation of antibiotics. In this work, CB[7] was shown to form binary host-guest complex with ambroxol hydrochloride (ABX), a clinical mucokinetic and expectorant drug, which was reported to exhibit certain antibacterial activity. 1 H NMR titration and isothermal titration calorimetry experiment results suggested that the 4-hydroxyl cyclohexylamine group of ABX was included inside the CB[7] cavity, with a binding constant K a of (6.69±0.11)×10 5 M −1 in phosphate buffered saline (PBS) solution, thermodynamically driven by both enthalpy change (ΔH=−12.2 kJ/mol) and entropy change (TΔS=21.1 kJ/mol). More importantly, ABX's inhibitory activity (MIC 50 ) against bacillary strains towards Pseudomonas aeruginosa and Escherichia coli strains was decreased from (5.11±0.31)×10 −6 M −1 and (2.63±0.34)×10 −5 M −1 to zero upon encapsulation by CB[7], and was subsequently recovered to almost its original activity when a competitive guest, amantadine hydrochloride, for disassembling CB[7]-ABX complex, was added, suggesting that the antibacterial activity of ABX could be readily “turned off/on” upon its complexation and decomplexation with CB[7].
研究领域:
药理学
·
微生物学
·
化学
✓ 已验证
DOI
高影响因子
Polymer Chemistry
·
2019
·Vol. 10
·期 44
·6021-6030
·
IF 4.76
Linfan Shi,Wenyi Wang,Xiong Fu,Yang Yuan,Bin Zhang,Qiang Huang
Ethylene was introduced into cucurbit[n]urils (CB[n]s, n = 5–7) by molecular encapsulation, for comparison with V-type crystalline starch (V-starch) and α-cyclodextrin (α-CD). The encapsulation capacity of inclusion complexes (ICs) followed the order of CB[5] > V-starch > CB[6] > CB[7] > α-CD. X-ray diffractometry, and 13C solid-state nuclear magnetic resonance and Fourier transform infrared spectroscopy confirmed the presence of ethylene gas in the solid matrices. The controlled release kinetics of the ICs were further studied under different storage temperature (4 and 25 °C) and relative humidity (52.9 and 75.5%) conditions. The Avrami equation was adapted to analyze the controlled release kinetics of ethylene gas, showing a diffusion limited mechanism for CB[n]-ICs under all the storage conditions. The ethylene release rate from CB[n]-ICs was accelerated by increasing ambient temperature, but was not sensitive to relative humidity. CB[5] showed the slowest ethylene release rate among the five solid matrices, up to 700 h under 4 °C storage conditions. Molecular simulation suggested two stable molecular conformations for ethylene molecules within the matrices, i.e., type I, two ethylene molecules in the cavity; and type II, one ethylene molecule in the cavity and the other one outside the cavity. CB[5] and CB[6] had a stable type II molecular conformation of ethylene, whereas CB[7] showed similar stability to type I and type II molecular conformations. For the first time, we demonstrated that CB[n]s (particularly CB[5]) are desirable gas storage and release systems for ethylene. This technology can enable precisely controlled and targeted applications of ethylene for food processing and agricultural applications.
研究领域:
食品科学
·
农业科学
·
材料化学
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF CONTROLLED RELEASE
·
2010
·
IF 5.949
Yulong Zhang,Fei Wu,Weien Yuan,Tuo Jin
Encapsulating delicate biomolecules into submicron-sized polymer particulate systems with preserved native conformation and sufficient loading efficiency is of great challenge. To address this issue, we developed a unique polymersome which differs from reported polymersome in that its bilayer membrane was formed of two different amphiphilic diblock copolymers in an “asymmetric” way. By adding two diblock copolymers, poly (ethylene glycol)- block -poly (ε-caprolactone) (PEG-PCL) and dextran- block -poly (ε-caprolactone) (DEX-PCL), into a so-called dextran-in-PEG aqueous two-phase system, DEX-PCL formed the inner leaflet around the dispersed dextran phase and PEG-PCL formed the outer leaflet with the PEG block facing the PEG continuous phase. We name this unique assembly process as “phase-guided assembly”. Polymersomes of asymmetric bilayer membrane possess a series of advantages over “symmetric” polymer bilayer vesicles previously reported. The asymmetric bilayer created a different chemical environment of the interior to which proteins were encapsulated highly efficiently (up to 90%) by thermodynamically favored partition. Probably due to the thermodynamic preference, erythropoietin (EPO) encapsulated in this system showed a well-preserved bioactivity in cell proliferation assay. The core of the polymersomes may be cross-linked to enhance their mechanical strength. Phase-guided assembly system and asymmetric bilayer polymersomes demonstrated in this study may serve the high demands for delivering nucleotide and protein medicines and other biological applications.
研究领域:
材料科学
·
生物医学工程
·
药物递送系统
✓ 已验证
DOI
PubMed
高影响因子
ACS Applied Materials & Interfaces
·
2019
·
IF 8.456
Dengfeng Ye,Lu Zhao,Shuaishuai Bai,Yongsheng Guo,Wenjun Fang
In this study, we described the synthesis, characterization, and application of hyperbranched polymer-encapsulated metal nanoparticles (HEMNs) as integrated catalysts for the supercritical cracking of hydrocarbon fuels. The metal precursor was extracted into the organic phase using a hydrocarbon-soluble hyperbranched poly(amidoamine) (CPAMAM) and then reduced in situ by NaBH4 to produce HEMNs with virtually a single-size distribution. The monitoring of the preparation process by UV–vis demonstrated the feasibility of this encapsulation approach, and the successful synthesis of three different types of HEMNs, metal (Pd, Pt, Au)@CPAMAM, reflected the universality of this method. Compared with the existing catalyst octadecylamine-stabilized Pd nanoparticle, Pd@18N, HEMNs were superior in every aspect. The new encapsulation method allowed metal NPs to have a smaller particle size beneficial to their overall specific surface area and a higher proportion of active surface atoms for a better catalytic activity. Moreover, the space-limiting effect of the polymer allowed the three HEMNs to be highly dispersed in decalin and exhibited admirable stability under storage tests for up to 12 months and high-temperature stability tests at 180 °C. During the supercritical cracking of decalin, Pd@CPAMAM possessed a much better catalytic performance than Pd@18N and CPAMAM (which can also be used as a macroinitiator). To obtain the same heat sink of 3.02 MJ/kg, the temperature could be lowered from 725 to 701, 693, and 699 °C for Pd, Pt, and Au HEMNs, respectively. Pt HEMN turned out to be the best due to its excellent catalytic dehydrogenation/cracking performance, with the conversion of decalin increasing from 22.3 to 50.7% and the heat sink rising from 2.18 to 2.62 MJ/kg with the existence of 50 ppm Pt@CPAMAM, at 675 °C. The significant enhancements were ascribed to the synergistic catalysis through the remarkable abilities of nanometals to catalyze dehydrogenation/cracking of fuel, the supercritical stabilization effects from CPAMAM, and the initiation effects of the hyperbranched polymer CPAMAM.
研究领域:
化学工程
·
催化科学
·
材料科学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
MACROMOLECULAR CHEMISTRY AND PHYSICS
·
2015
·Vol. 217
·期 3
·380-389
·
IF 2.616
Yaochen Zheng,Aijin Tang,Zhulin Weng,Shengying Cai,Yu Jin,Zhengguo Gao,Chao Gao
A novel kind of amphiphilic hyperbranched poly(propargyl quaternary ammomium methacrylate)- co -polymethyl methacrylate (HPPrAM- co -PMMA) is facilely synthesized via a combination of self-condensing vinyl polymerization (SCVP), reversible addition-fragmentation chain transfer (RAFT) polymerization, and a highly efficient Menschutkin reaction. With water soluble quaternary ammonium salt moieties and hydrophobic PMMA segments, the amphiphilic HPPrAM- co -PMMA is further employed as the host molecule for anionic dye supermolecular encapsulation. Due to the strong electrostatic interaction and large polar difference between the HPPrAM and PMMA moieties, the AHP exhibits a high loading capability of water soluble dyes ( C dyes ) (such as rose bengal, methyl orange, and fluorescein sodium). Furthermore, the AHP-dye complex is used as a coloring additive for common polymers, such as styrene- block -butadiene- block -styrene copolymer (SBS) and poly(methyl methacrylate) (PMMA). A sample colored with the AHP-dye complex shows good dye dispersion, uniformity, and coloring stability.
研究领域:
材料科学
·
高分子化学
·
超分子化学
✓ 已验证
DOI
高影响因子
AAPS PHARMSCITECH
·
2023
·Vol. 24
·期 5
·1-11
·
IF 3.3
Zhang Ying,Chen Jiacai,Zhang Zaiyong,Zhu Huajie,Ma Wuzhen,Zhao Xiangyu,Wang Manli,Wang Caifen,Chen Weidong,Naeem Abid,Zhang Jiwen,Guo Tao,Wu Li
Cyclodextrin metal-organic frameworks (CD-MOFs) exhibit a high structural diversity, which contributes to their functional properties. In this study, we have successfully synthesized a novel type of β-cyclodextrin metal-organic framework (β-CD-POF(I)) that exhibits excellent drug adsorption capacity and enhances stability. Single-crystal X-ray diffraction analysis revealed that β-CD-POF(I) possessed the dicyclodextrin channel moieties and long-parallel tubular cavities. Compared with the reported β-CD-MOFs, the β-CD-POF(I) has a more promising drug encapsulation capability. Here, the stability of vitamin A palmitate (VAP) was effectively improved by the solvent-free method. Molecular modeling and other characterization techniques like synchrotron radiation Fourier transform infrared spectroscopy (SR-FTIR), differential scanning calorimetry (DSC), powder X-ray diffraction (PXRD), thermogravimetric analysis (TGA), and nitrogen adsorption isotherm were applied to confirm that the VAP was successfully encapsulated into the channel formed by the dicyclodextrin pairs. Furthermore, the mechanism of stability enhancement for VAP was determined to be due to the constraint and separation effects of β-CD pairs on VAP. Therefore, β-CD-POF(I) is capable of trapping and stabilizing certain unstable drug molecules, offering benefits and application possibilities. Graphical abstract
One kind of cyclodextrin particle with characteristic shapes of dicyclodextrin channel moieties and parallel tubular cavities, which was synthesized by a facile process. Subsequently, the spatial structure and characteristics of the β-CD-POF(I) were primarily confirmed. The structure of β-CD-POF(I) was then compared to that of KOH-β-CD-MOF, and a better material for vitamin A palmitate (VAP) encapsulation was determined. VAP was successfully loaded into the particles by solvent-free method. The arrangement of spatial structure made cyclodextrin molecular cavity encapsulation in β-CD-POF(I) more stable for VAP capture than that of KOH-β-CD-MOF.
研究领域:
药学
·
材料科学
·
生物化学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
Journal of Materials Chemistry B
·
2018
·Vol. 6
·期 16
·2474-2480
·
IF 4.776
Lin Li,Changping Wang,Quan Huang,Jianru Xiao,Qiang Zhang,Yiyun Cheng
Hydrogels can be used to prolong the retention of photothermal agents in tumors to conduct repeated photothermal therapy (PTT) and thus reduce high-dose-induced toxicity, but the long-term retention of photothermal nanoparticles post-therapy still increases the risk of toxicity. In this work, we developed an injectable and degradable photothermal hydrogel to conduct repeated PTT. The hydrogel was composed of dendrimer-encapsulated platinum nanoparticles (DEPts) crosslinked aldehyde-modified dextran via imine bond formation. The hydrogel represented excellent photothermal effect and good biocompatibility. It was able to remain in tumors for a period of days to allow repeated PTT, leading to complete tumor regression. After treatment, the hydrogel was gradually degraded due to the decomposition of imine bonds. The study developed a practical photothermal hydrogel that allowed repeated PTT and reduced long-term retention-induced toxicity.
研究领域:
纳米技术
·
癌症治疗
·
生物材料
·
生物医学工程
✓ 已验证
产品关联
DOI
PubMed
高影响因子
危险品化学品经营许可证（带存储）