Polymer Chemistry
·
2017
·Vol. 8
·期 43
·6675-6687
·
IF 5.375
Da Huang,Yaqiang Wang,Fei Yang,Hong Shen,Zuquan Weng,Decheng Wu
Recently, nanoparticles self-assembled from amphiphilic supramolecular linear-dendritic block copolymers (LDBCs) have attracted great interest, since the combination of linear and dendritic polymers can incorporate the unique properties of the different segments but avoid some inherent drawbacks of dendrimers, not to mention that the components can be flexibly adjusted to enrich their functionality. In this study, LDBCs formed by host–guest recognition of polyacetal dendrimers with a β-cyclodextrin core and adamantane-terminated zwitterionic poly(sulfobetaine) could self-assemble into micelles and vesicles by varying the hydrophilic/hydrophobic ratio. Owing to the acid-labile characteristic of the dendritic segments, the micelles and vesicles were degradable and could release their payloads in a pH-responsive manner. The incorporation of zwitterionic linear segments gave the micelles and vesicles a charge-reversal ability and excellent resistivity to protein absorption, leading to higher affinity to cell membranes than conventional PEG-coated nanoparticles. In addition, the potential of these nanoparticles as anticancer drug carriers was preliminarily evaluated by using doxorubicin as a model drug and the results indicated that the DOX-loaded micelles and vesicles exhibited remarkable anticancer activity. This study cast a new light on the application of dendrimers and these micelles and vesicles constructed from LDBCs may be promising candidates as anticancer drug delivery platforms for cancer therapy.
研究领域:
生物材料学
·
药剂学
·
肿瘤学
✓ 已验证
DOI
高影响因子
ACS Omega
·
2017
·
IF 0
Jie Feng,Yonglei Chen,Yangxia Han,Juanjuan Liu,Sudai Ma,Huige Zhang,Xingguo Chen
In this article, a simple protocol to prepare water-soluble fluorescent copper nanoclusters (CuNCs) using trypsin as a stabilizer and hydrazine hydrate as a reducing agent was reported. It was found that the pH of the reaction solution was critical in determining the fluorescence of CuNCs. CuNCs with blue and yellow fluorescent emission were obtained under basic and acidic conditions, respectively. Although the detailed formation mechanisms of these CuNCs required further analysis, the synthetic route was promising for preparing different fluorescent metal NCs for applications. With good water solubility and excellent photostability, the yellow-emitting CuNCs could serve as a fluorescence probe for detection of Hg2+ based on the aggregation-induced quenching mechanism. The fluorescence quenching efficiency had fantastic linearity to Hg2+ concentrations in the range of 0.1–100 μM, with a limit of detection of 30 nM. Additionally, the yellow-emitting CuNCs exhibited negligible cytotoxicity and were successfully applied to bioimaging of HeLa cells.
研究领域:
纳米技术
·
分析化学
·
生物医学工程
·
材料科学
✓ 已验证
DOI
PubMed
COLLOID AND POLYMER SCIENCE
·
2015
·Vol. 293
·期 12
·3517-3526
·
IF 1.865
He Naipu,Lu Zhenwu,Zhao Weigang
Double hydrophilic protein-polymer hybrids were successfully prepared by “grafting-to” method. Sodium polyacrylate (PANa) with an activated end group was prepared using acrylic acid as initial monomer by atom transfer radical polymerization (ATRP) in the water/DMF mixture at pH 7.8. Then, the activated end group of PANa directly covalently binds to the primary amino groups of the lysine of bovine serum albumin (BSA) in phosphate buffer solution (PBS) at pH 7.4. BSA-PANa hybrids were characterized by sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE) and matrix-associated laser desorption/ionization time-of-flight mass spectra (MALDI-ToF MS). UV-vis spectrometer, transmission electron microscopy (TEM), and dynamic light scatter (DLS) were used to study their self-assembly in PBS at different pH. The resulting BSA-PANa hybrids were pH-responsive. They were found to form spherical structures with narrow distribution in PBS at pH 7.4. In PBS at pH 2.5, fewer spherical particles with broad distribution were visible. Meanwhile, spherical particles had a very thin wall with thickness of 10 nm.
The table of contents (ToC) The resulting BSA-PANa hybrids were found to be pH-responsive. The self-assembly aggregates were found to form spherical structures with a diameter of approximately 100 nm phosphate buffer solution (PBS) at pH 7.4. In PBS at pH 2.5, the diameters of spherical particles varied between 80 and 200 nm. Meanwhile, spherical particles had a very thin wall with thickness of 10 nm.
研究领域:
材料科学
·
聚合物化学
·
生物物理
✓ 已验证
DOI
高影响因子
CHINESE JOURNAL OF CHEMISTRY
·
2021
·Vol. 39
·期 10
·2852-2856
·
IF 6
Peng Zhou,Zixian Li,Yanzhi Lu,Jie Kong,Jun Ling
Main observation and conclusion Block copolymers not only combine properties of different segments but also generate new application prospects. Poly(α-amino acid)- b -poly(tetrahydrofuran)- b -poly(α-amino acid) (PAA-PTHF-PAA) is one of the copolymers. In this contribution, di-hydroxyl-ended HO-PTHF-OH is transferred into di-oxyamino-ended H 2 NO-PTHF-ONH 2 quantitatively, which is used as a macroinitiator to polymerize sarcosine N -thiocarboxyanhydride (Sar-NTA) and N -phenyoxycarbonyl N -ε-carbobenzyloxy- D -lysine (ZDL-NPC). Well-defined triblock PAA-NHO-PTHF-ONH-PAA is produced with high molecular weight (up to 25.3 kg/mol) and narrow dispersity. The amphiphilic PSar-NHO-PTHF-ONH-PSar (STS) self-assembles into micelles with uniform diameters of 30—40 nm according to DLS. Owing to oxygen amide groups inside the backbone of these copolymers, the polyether-poly(amino acid)s block copolymers are cleavable under an acidic environment and therefore have potential applications in smart biomedicine and engineering.
研究领域:
高分子化学
·
生物材料
·
生物医药
✓ 已验证
DOI
高影响因子
Quantitative Imaging in Medicine and Surgery
·
2022
·
IF 4.63
Quan Tao,Peiwei Yi,Zimeng Cai,Zelong Chen,Zongwu Deng,Ruiyuan Liu,Yanqiu Feng
Background As an essential physiological parameter, pH plays a critical role in maintaining cellular and tissue homeostasis. The ratiometric chemical exchange saturation transfer (CEST) magnetic resonance imaging (MRI) method using clinically approved iodinated agents has emerged as one of the most promising noninvasive techniques for pH assessment. Methods In this study, we investigated the ability to use the combination of two different nonequivalent amide protons, chosen from five iodinated agents, namely iodixanol, iohexol, iobitridol, iopamidol, and iopromide, for pH measurement. The ratio of two nonequivalent amide CEST signals was calculated and compared for pH measurements in the range of 5.6 to 7.6. To quantify the CEST signals at 4.3 and 5.5 parts per million (ppm), we employed two analytic methods: magnetization transfer ratio asymmetry and Lorentzian fitting analysis. Lastly, the established protocol was used to measure the pH values in healthy rat kidneys (n=5). Results The combination of iodixanol and iobitridol at a ratio of 1:1 was found to be suitable for pH mapping. The saturation power level (B 1 ) was also investigated, and a low B 1 of 1.5 µT was adopted for subsequent pH measurements. Improved precision and an extended pH detection range were achieved using iodixanol and iobitridol (1:1 ratio) and a single low B 1 of 1.5 µT in vitro . In vivo renal pH values were measured as 7.23±0.09, 6.55±0.15, and 6.29±0.23 for the cortex, medulla, and calyx, respectively. Conclusions These results show that the ratiometric CEST method using two iodinated agents with nonequivalent amide protons could be used for in vivo pH mapping of the kidney under a single low B 1 saturation power.
研究领域:
医学影像学
·
生物医学工程
✓ 已验证
DOI
PubMed
高影响因子
Journal of Water Process Engineering
·
2020
·
IF 3.465
Chang Tian,Yan-Xia Zhao
Polytitanium coagulants have been recently developed and have received wide attention due to both strong coagulation capability and sludge recycling to produce valuable by-products, titanium dioxide (TiO 2 ). This study reports the performance of coagulation with emerging polytitanium salts, polytitanium chloride (PTC) and polytitanium sulfate (PTS), for the treatment of two common cyanobacteria ( Microcystis aeruginosa , MA and Microcystis wesenbergii , MW)-laden surface water, which has been barely reported. Of particular concern is the coagulant dosage and solution pH dependence of polytitanium coagulation, which are the main parameters influencing coagulation efficiency. The influence of basicity (B) of PTC and PTS on coagulation performance was simultaneously included. Results show the optimized B value of 1.5 with coagulant dosage of 30 mg/L and initial solution pH between 7–9 for both PTC and PTS coagulation, wherein obvious advantage of PTC was observed over PTS regardless of MA- or MW-laden surface water treatment. The PTC coagulation could achieve almost complete removal of algae (about 99.0 %) with synergic removal of organic matter with high-efficiency. Both PTC and PTS were more capable at alkaline solution pH conditions for turbidity and algae removal through sweep flocculation, while satisfied removal of the humic acid-representative organic matters was observed at acidic to neutral pH conditions by charge neutralization. Satisfied flocculation zones were determined according to synergic removal of algae, turbidity and organic matters, with most of the satisfied points distributed at solution pH 7–9 conditions. This study will provide theoretical basis and facilitate wide application of the polytitanium coagulation for algae-loaded surface water treatment.
研究领域:
环境工程
·
水处理
·
胶体与界面化学
·
环境化学
·
给排水科学与工程
✓ 已验证
DOI
高影响因子
Acta Biomaterialia
·
2016
·
IF 6.008
Maohua Chen,Yun Zhang,Zhoujiang Chen,Songzhi Xie,Xiaoming Luo,Xiaohong Li
Challenges remain to load and deliver two or multiple drugs of complementary effects for synergistic cancer therapies. In the current study, multiarmed amphiphilic copolymers of 4-arm poly(ethylene glycol) (PEG) and polyaspartate (PAsp) are created for conjugation of camptothecin (CPT) and condensation with tumor necrosis factor-α (TNF) plasmids. Diethylenetriamine (DET) is grafted on PAsp, and CPT is conjugated onto PAsp(DET) by disulfide linkages to form hydrophobic cores of micelles , followed by condensation with TNF plasmids to form micelleplexes. The cis -aconitic linkers are introduced between PEG and PAsp(DET) to remove PEG shells in response to acidic pH, resulting in destabilized micelleplexes and prompted endosomal escape into the cytosol. The micelleplex disintegration in response to reductive stimuli in the cytosol leads to an efficient CPT release and pDNA disassociation. The co-delivery of CPT with TNF plasmids enhances the gene transfection of micelleplexes at low N/P ratios, and shows synergetic cytotoxicities to tumor cells with 2.5 and 8 folds lower IC 50 s compared with those after treatment with CPT or TNF alone, respectively. The micelleplex treatment on 4T1 tumor models dramatically extends the animal survival and suppresses the tumor growth with 2.3 and 3 folds lower in volume compared with CPT or TNF treatment alone, respectively. Histological and biochemical analyses display TNF expressions in tumor tissues after micelleplex treatment, resulting in significantly larger necrotic regions in tumors, higher cell apoptosis rates , and no obvious sign of tumor metastasis in lungs compared with other treatment. Therefore, the multifunctional micelleplexes based on multiarmed PEG-PAsp(DET) copolymers offer the targeted drug/gene delivery, dually responsive drug/gene release and synergistic antitumor efficacy, holding great promises for combination therapies. Statement of Significance Micelleplexes are constructed from multiarmed amphiphilic copolymers with conjugation of captothecin (CPT) and condensation of tumor necrosis factor-α (TNF) plasmid. The pH/redox stimuli realize co-delivery of CPT and pDNA in a sequential manner of folate-mediated endocytosis , endosomal escape induced by PEG cleavage, reduction-sensitive release of CPT in cytosol, and pDNA release from disintegrated polyplexes after CPT release. Compared with CPT or TNF treatment alone, the micelleplexes achieve 2.5 and 8 folds higher cytotoxicities to tumor cells, and suppress the tumor growth with 2.3 and 3 folds lower in volume, respectively. It demonstrates a feasible strategy to develop multifunctional micelleplexes with simultaneous drug conjugation and pDNA condensation, dually responsive drug/gene release and synergistic antitumor efficacy, holding great promise for combinational therapies.
研究领域:
药剂学
·
肿瘤学
·
生物材料科学
✓ 已验证
DOI
PubMed
高影响因子
ACS Sustainable Chemistry & Engineering
·
2015
·
IF 4.642
Chen Feng,Shaoyu Lü,Chunmei Gao,Xinggang Wang,Xiubin Xu,Xiao Bai,Nannan Gao,Mingzhu Liu,Lan Wu
With the fast development of sustainable modern agriculture, there has been a shift toward the development of controlled/slow release fertilizers (CSRFs) that can overcome current limitations of conventional fertilizers. Ideally, CSRFs would release nutrient matching plants demands, even when environmental conditions fluctuate. However, no current CSRFs meet this ideal, especially as nutrient release is affected by temperature and pH. In this study, a “smart” fertilizer with polymer brushes of poly(N,N-dimethylaminoethyl methacrylate) grafting from polydopamine-coated ammonium zinc phosphate via surface-initiated atom-transfer radical polymerization is reported. The structure and morphology of the fertilizer were measured by transmission electron microscopy (TEM); the composition of the product was determined with Fourier transform infrared (FTIR) spectroscopy, thermogravimetric analysis (TGA), and inductively coupled plasma (ICP) emission spectrometer. Dual-responsive controlled-release behaviors were characterized in water by spectrophotometry and ICP, and results demonstrate the “smart” fertilizer shows excellent temperature- and pH-responsive behavior to release nutrients according to the ambient environment. The nutrients release rate can be obviously accelerated in an acidic pH (below pKa) medium at a definite temperature. In addition, low temperature (below LCST) can accelerate the nutrients release rate in a basic medium (above pKa), which is contrasting to the reduction of nutrients release rate at high temperature (above LCST) in the same medium. The pH- and temperature-responsive “smart” fertilizer will improve nutrients availability and avoid excessive release of nutrients causing damage to plant roots at high temperature, which indicating that the stimuli-responsive system has potential application in sustainable modern agriculture.
研究领域:
农业科学
·
材料科学
✓ 已验证
DOI
高影响因子
CHEMICAL ENGINEERING JOURNAL
·
2016
·
IF 5.31
Guilin He,Cong Li,Tuqiao Zhang,Jingguo Zhao,Virender K. Sharma,Leslie Cizmas
Chloramination of bisphenol A (BPA) in a pilot-scale water distribution system (WDS) was investigated to assess factors that influence degradation rate and degradation products. In deionized water (DW) and in the WDS, complete degradation of BPA after chloramination required >9 h. At Cl/N mass ratios of 3, 4 or 6, the degradation rate was appreciably greater in the WDS than in the DW. In both the DW and WDS, the bromide ion concentration had little influence on BPA degradation. The BPA degradation rate was greatly affected by pH and temperature in both the DW and in the WDS. The rate of BPA degradation by chloramination increased with increasing flow velocity, but the increase was limited. The BPA degradation rate in different pipes followed the order: ductile iron pipe > polyethylene (PE) pipe > stainless steel pipe. Twelve specific degradation products of BPA that were produced following chloramination were tentatively identified, with 2-chloro-BPA as the main byproduct. One nitrogenous byproduct produced following chloramination was detected for the first time, and appeared at 15 min, indicating that nitrogen from the chloramine participated in the BPA degradation reaction at the beginning of the experiment. In the presence of chloramines and BPA, the formation of trihalomethanes (THMs), haloacetic acids (HAAs) and halogenated nitromethane (HNMs) occurred primarily in the initial 3 h. The intermediates of BPA that were formed during chloramination had relatively little influence on THM, HAA and HNM formation. The degradation pathways for BPA during chloramination in the WDS are proposed.
研究领域:
环境科学
·
水处理工程
·
化学
✓ 已验证
DOI
高影响因子
APPLIED ORGANOMETALLIC CHEMISTRY
·
2025
·Vol. 39
·期 6
·e70227
·
IF 0
Safdar Ali Amur,Quratulain Khuhro,Najaf Ali Soomro,Muhammad Tariq,Hao Liang,Khalid Hussain Thebo,Mohsin Kazi
This study reports a green one-pot synthesis of glabridin-loaded Zeolitic Imidazolate Framework-8 (Glab@ZIF-8) drug delivery system (DDS) with exceptional drug loading encapsulation (DLE) of ≈ 98.7% and drug loading capacity (DLC) of 32%, surpassing values reported in previous ZIF-8-based DDS. Characterizations using Fourier-transform infrared (FTIR), UV–Visible spectroscopy, dynamic light scattering (DLS), and X-ray diffraction (XRD) confirmed successful encapsulation of Glab within ZIF-8 while preserving its crystallinity. Glab@ZIF-8 exhibited a hexagonal morphology with increased particle size (138.6 ± 5.4 nm) and a higher zeta potential (+41.9 mV), suggesting enhanced colloidal stability and efficient drug entrapment. Thermogravimetric analysis (TGA) demonstrated a total of 32.1% decomposition of Glab@ZIF-8 up to 644 °C. Antibacterial assays revealed that Glab@ZIF-8 exhibited superior activity against Staphylococcus aureus (inhibition zone: 26.2 ± 0.3 mm) and Escherichia coli (23.3 ± 0.2), comparable to that of ampicillin. The minimum inhibitory concentration (MIC) was determined to be 32.5 μg/100 μL. Furthermore, the time-kill studies confirmed a dose- and time-dependent antibacterial effects of Glab@ZIF-8. In vitro drug release studies showed strong pH- and temperature-responsive behavior, with a cumulative release of 93.7% ± 2.4% release at pH 5 (at 37°C) over 72 h. The Glab@ZIF-8 system thus combines high drug loading efficiency, excellent antibacterial activity, and tuneable release characteristics, highlighting its potential as a promising DDS for combating drug-resistant infections.
研究领域:
药剂学
·
微生物学
·
材料科学
✓ 已验证
产品关联
DOI
JOURNAL OF COLLOID AND INTERFACE SCIENCE
·
2016
·
IF 3.782
Xinyun Zhu,Cai-Qi Wang
A pH and redox dual-responsive nanovalve with a long stalk was introduced on the surface of hollow mesoporous silica nanoparticles (HMSs-S1) to achieve cargo size selectivity delivery. The responsive nanovalve was designed by constructing of a stalk/β-cyclodextrins (CDs) supramolecular complex, which is based on an acid-labile acetal group and the host–guest interactions between β-cyclodextrins and ferrocenyl moiety (Fc). With stimulation by different pH and H 2 O 2 , Rhodamine 6G showed well-responsive behavior. On account of the long stalks of nanovalve, doxorubicin hydrochloride and 5-fluorouracil with different sized cargos are encapsulated in HMSs-S1 to test its behavior of cargo size-selective delivery. Moreover the HMSs-S2 with a short stalk based on β-CDs/Fc inclusion complex is synthesized to load small sized 5-FU drug as contrast experiment. Compared with HMSs-S2, HMSs-S1 is compatible with larger drug molecules such as Rhodamine 6G (R6G) and doxorubicin hydrochloride (DOX), while small sized 5-fluorouracil (5-FU) is unable to be sealed by the nanovalve. Dual responsiveness and drug size selectivity make mechanized HMSs possess potential applications in drug delivery system.
研究领域:
材料科学
·
药物递送系统
·
纳米医学
✓ 已验证
DOI
高影响因子
POLYMER
·
2013
·
IF 3.379
Runnan Zhang,Yanlei Su,Jinming Peng,Xiaochen Fan,Zhongyi Jiang,Xueting Zhao,Jiazhen Liu,Yafei Li,Jiaojiao Zhao
In the present study, an in situ approach to pH and temperature responsive membranes is developed. The membrane matrix is formed through bulk polymerization and crosslinking of liquid monomer 2-hydroxyethyl methacrylate (HEMA) while the membrane pores are formed by the templating of inorganic particles . The functional monomers methacrylic acid (MAA) and N-isopropylacrylamide (NIPAAm) are incorporated into membrane casting solution in order to confer membranes with pH and temperature responsive properties. The poly(HEMA/MAA) membranes exhibit a reversible pH-dependent water flux, while the poly(HEMA/NIPAAm) membranes exhibit a reversible temperature-dependent water flux. The flux of the poly(HEMA/MAA) membrane increased by 70% when pH was decreased from 10.0 to 2.0, while the flux poly(HEMA/NIPAAm) membrane increased by 150% when temperature was increased from 20 to 45 °C. The protein adsorption and antifouling performance of the poly(HEMA/MAA) and poly(HEMA/NIPAAm) membranes also exhibit pH and temperature responsive properties.
研究领域:
高分子材料科学
·
膜科学与技术
·
生物医学工程
·
智能响应材料
·
分离科学
·
表面功能化
✓ 已验证
DOI
高影响因子
危险品化学品经营许可证（带存储）