JOURNAL OF BIOMATERIALS SCIENCE-POLYMER EDITION
·
2023
·
IF 3.6
XiaoNan Zhang,WenQin Xu,Xing Li,GuangHua Pan,NanChun Chen,QingLin Xie,XiuLi Wang
This experiment was done to study the zeolite molecular sieve as a drug-binding effector, the non-antibiotic drug potassium diformate uniformly disperse in the internal aqueous phase of the 'egg box' structure formed by pectin-calcium ions. With oil phase as the intermediate phase and Xanthan gum Chitosan as the external water phase, the W/O/W type sustained release bacteriostatic microcapsules with pH response were prepared and characterized by Fourier transform infrared, thermogravimetric, SEM, and TEM. It can be obtained through characterization experiments that the inner water phase, oil phase, and outer water phase were formed by observation, and W/O/W emulsion microcapsules were obtained and the bacteriostasis effect of microcapsules was verified by bacteriostasis experiment. The permeance experiment showed that the molecular sieve was successfully coated in the microsphere. Studying on drug release mechanism and sustaining release performance of composite emulsion microcapsules. In vitro drug release study showed that the encapsulation efficiency and drug loading rate of microcapsules were improved by adding molecular sieve, reaching 12.31% and 61.55%, respectively. At the same time, we observed that the drug release rate slowed down during the simulated intestinal release process, and the drug release kinetics were in line with the first-order kinetic model and Ritger-Peppas model equation. Experiments had proven that the drug-loaded microcapsules exerted a significant bacteriostatic effect on Escherichia coli, Staphylococcus aureus, and Bacillus subtilis, with the highest antibacterial rates of 97.25%, 94.05%, and 95.93%, respectively. Therefore, the composite emulsion microcapsules can be used as a new controlled-release drug delivery system in vivo.
研究领域:
药物递送系统
·
材料科学
·
微生物学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
JOURNAL OF SOILS AND SEDIMENTS
·
2021
·Vol. 21
·期 2
·775-783
·
IF 3.308
Du Huihui,Du Jingwei,Liu Fangyi,Zhang Yanhuan,Guo Hanwen,Wan Dan
Purpose Antibiotics often coexist with heavy metals in contaminated soils, making their behaviors more complicated than their individual presences. Sorption to soil components deeply affects the mobility, bioavailability, and fate of contaminants. However, limited studies have investigated the cosorption characteristics of tetracycline (TC) and heavy metals to typical soil minerals, particularly phyllosilicates. Materials and methods This study investigates the effect of Cd(II) on TC sorption by kaolinite (Kao, 1:1-type) and montmorillonite (Mont, 2:1-type) via isothermal adsorption, coupled with X-ray diffraction (XRD) and Fourier transform infrared spectroscopy (FTIR). Results and discussion Isothermal results show that TC sorption on both kaolinite (Kao, 1:1-type) and montmorillonite (Mont, 2:1-type) is little affected by Cd(II) at pH 4.5 but increases significantly at pH 8.5. The overall effect of Cd(II) on TC sorption depends on the intensities of two positive processes, i.e., (1) the formation of soluble Cd-TC complex increases sorption compared to free TC molecules and (2) the formation of a ternary clay-Cd-TC complex at clay variable edge sites increases sorption, and one negative process, i.e., competition of Cd(II) with cationic and zwitterionic TC species at the permanently charged sites decreases sorption. XRD analyses demonstrate that TC intercalates into the interlayer ( d 001 = 18.7 Å) of Mont as one monolayer parallel molecule both with and without Cd(II) but adsorbs predominately on external surface of Kao. FTIR results suggest a flat-lying horizontal configuration of adsorbed TC molecules on clays, accompanied by a strong complexation between the carbonyl and amino groups of TC molecules and the surfaces. Besides, the presence of Cd(II) more or less facilitates this complexation. Conclusions We propose that Cd(II) can significantly promote TC adsorption on clay minerals at alkaline pH rather than acidic pH. TC and Cd(II) interact intensely and form strong surface complexation on clay surfaces. Hence, coexistence with Cd(II) may lower the mobility and thus the bioavailability of TC in alkaline soils, which provides a new direction for soil remediation by regulating soil pH using alkaline materials. Graphical abstract
研究领域:
环境科学
·
土壤学
✓ 已验证
DOI
高影响因子
JOURNAL OF GENERAL AND APPLIED MICROBIOLOGY
·
2016
·
IF 1
Alei Zhang,Cong Gao,Kequan Chen,Ce Wei,Pingkai Ouyang
The pH of a microbiological culture is important for both cell growth and chitinase accumulation, but the optimal pH is not normally the same for both. The objective of this study was to investigate the effect of pH on chitinase production by Chitinolyticbacter meiyuanensis strain SYBC-H1 (ATCC BAA-2140) in a mineral medium. The results of batch culture at different pH values showed that the optimum pH for cell growth and chitinase production varied with time, although KOH produced the best results for cell growth and chitinase production, NaOH was chosen because of cost considerations. We designed a three-stage pH control strategy using NaOH as the neutralizing agent. Maximum cell growth (1.07 g dry cell weight/l) and maximum chitinase activity (13.6 U/ml) were observed after culture at 26°C for 72 h in a mineral medium. These values were greater by 129% and 162%, respectively, and the length of time to attain maximum chitinase activity was decreased by 12 h, compared with results from an earlier study (Hao et al., 2011b).
研究领域:
微生物学
·
生物技术
✓ 已验证
DOI
PubMed
高影响因子
CHEMICAL ENGINEERING JOURNAL
·
2019
·
IF 8.355
Shengtao Xing,Wenqing Li,Bo Liu,Yinsu Wu,Yuanzhe Gao
CuO synthesized by a hydrothermal method was used to activate persulfate (PS) for removing ciprofloxacin (CIP) in water. The influences of reaction parameters and coexisting substances on this process were studied. Under the optimal conditions ([CuO] 0 = 6.3 mmol L −1 , [PS] 0 = 1 mmol L −1 , pH 8), CIP was completely degraded and the total organic carbon removal efficiency was 84.2%. Ca 2+ , Mg 2+ and Cl − had little effect on CIP removal, while fulvic acid showed a slight inhibitory effect. By contrast, bicarbonate enhanced CIP degradation and significantly suppressed Cu leaching. Subsequently, the reactive species for CIP degradation were identified by electron paramagnetic resonance and radical scavenging experiments. Although the decomposition efficiency of PS was significantly accelerated by increasing pH, similar amounts of O 2 − , OH, SO 4 − and 1 O 2 were detected at different pH, suggesting the formation of more surface activated PS at higher pH. The reactive species for CIP degradation were found to be dependent on solution pH. CIP was mainly degraded by SO 4 − and 1 O 2 at acidic conditions. The activated PS might have high selectivity towards CIP and its amount might be higher than that of radicals at pH 8. In addition, the uncharged surface of CuO at pH 8 facilitated the adsorption of CIP, which is beneficial to the surface reaction between CIP and activated PS. Hence, the activated PS was the dominated species for CIP degradation at this pH.
研究领域:
环境科学
·
化学工程
✓ 已验证
DOI
高影响因子
LANGMUIR
·
2018
·
IF 3.789
Jiaxing Sun,Jiefu Li,Dezhong Liu,Ying Ma,Shuguang Yang
Poly(acrylic acid) (PAA) was partially grafted with dopamine (PAA-dopa), and then layer-by-layer assembled with poly(vinylpyrrolidone) (PVPON) to prepare hydrogen-bonded (PVPON/PAA-dopa)n film. Polydopamine (PDA) was deposited on (PVPON/PAA-dopa)n film in the presence of oxidant, and hence the whole (PVPON/PAA-dopa)nPDA film was cross-linked. (PVPON/PAA-dopa)nPDA could be utilized as a platform to produce the free-standing Janus film because of the easy detaching process and various chemical reactivity of PDA layer. Ag nanoparticles were formed on (PVPON/PAA-dopa)nPDA film by electroless metallization. 1H,1H,2H,2H-Perfluorodecanethiol (PFDT) was used to further modify the film through Michael addition. After detaching from the substrate, (PVPON/PAA-dopa)20PDA/Ag/PFDT exhibits reversible swelling–shrinking behavior as the pH value changes. This free-standing film shows Janus character, one side is hydrophobic, whereas the other side is hydrophilic. In addition, the hydrophobic surface exhibits a surface-enhanced Raman scattering effect, whereas the hydrophilic side does not.
研究领域:
材料科学
·
表面化学
·
纳米技术
✓ 已验证
DOI
高影响因子
INORGANIC CHEMISTRY
·
2025
·
IF 4.7
Jun-Ru Tian,Jie-Yao Song,Zhongchang Wang
Conventional fluorescent pH sensors, despite offering high sensitivity and rapid response, are limited by their reliance on fluorescence intensity changes, hindering applications requiring precise wavelength control. Here, we present a pH sensing strategy based on cross-linked carbon quantum dots (CCL-CQDs) displaying a remarkable pH-dependent red shift in the fluorescence emission wavelength. Amino- and carboxyl-functionalized CQDs were synthesized via a one-step hydrothermal method and further assembled into CCL-CQDs through the condensation reaction between amino groups and glutaraldehyde. The CCL-CQDs displayed excellent pH sensitivity, with their fluorescence emission wavelength exhibiting a linear red shift upon increasing pH (from 2.29 to 7.16). The results of mechanism exploration revealed that H+ induced the cleavage of C═N bonds in the CCL-CQD structure, leading to the formation of –COOH groups and increased surface-oxidized carbon content. This enhanced oxidation generated more surface defects, triggering a wavelength shift in surface-state-related fluorescence emission. This study demonstrates the successful synthesis of pH-sensitive CCL-CQDs with an excellent fluorescence detection performance.
研究领域:
材料科学
·
分析化学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
JOURNAL OF WUHAN UNIVERSITY OF TECHNOLOGY-MATERIALS SCIENCE EDITION
·
2024
·Vol. 39
·期 4
·1048-1052
·
IF 1.3
Yu Dan,Ye Liyuan,Li Binbin,Mou Fangzhi,Yin Yixia
pH-responsive charge reversal loaded miRNA nanocomposite was prepared by electrostatic self-assembly. The morphology, particle size and zeta potential of the nanocomposites were analyzed by transmission electron microscopy and dynamic light scattering. The synthesis of the polymer was analyzed by 1 H-NMR. The zeta-potential changes and cellular uptake effects of the nanocomplexes under different pH environments were investigated. The experimental results show that the surface morphology of the nanocomposite is spherical, and the average particle size is about 135 nm. As the pH value of the solution gradually decreases, the surface charge of the nanocomposite reverses from negative charge to positive charge (from −9.4 to +17.1 mV). Cellular uptake mediated by pH-responsive nanocomposite is selective for tumor cells, and the cellular uptake effect in tumor cells at pH 6.5 was approximately 3 times higher than that at pH 7.4. This pH responsive charge reversal nanocomposite has promising application prospects for gene delivery in the weak acid environment of tumors.
研究领域:
生物材料学
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分子生物学
·
药物递送系统
✓ 已验证
产品关联
DOI
高影响因子
INTERNATIONAL JOURNAL OF HYDROGEN ENERGY
·
2024
·
IF 8.1
Xiaojing Dong,Yangyang Wang,Jintao Wang,Yiqiang Sun,Bo Xu,Cuncheng Li,Lifeng Hang
In the field of research on renewable energy conversion and storage methods, the development of catalysts with excellent properties and outstanding stability for oxygen evolution reaction (OER) acting at various pH values has become a much-anticipated research focus. RuO 2 as a benchmark OER catalyst, its wide application has always been limited by slow reaction kinetics and limited persistence. In this paper, Mn-doped RuO 2 material was developed and the optimum doping ratio was identified for using as an OER electrocatalyst under general purpose pH media. Mn 0.1 Ru 0.9 O 2 exhibited a lower overpotential value of 224 mV in acidic environment with a Tafel slope value of 51.62 mV dec −1 . Moreover, in alkaline and neutral environments, overpotentials of 231 mV and 376 mV were required to obtain a current density of 10 mA cm −2 , respectively. In addition, through continuous stability testing over 24 h in alkaline, acidic and neutral solutions, it has been further demonstrated that the Mn-doped RuO 2 material exhibits extremely high stability. The advancements in this research offer crucial insight into the rational development of efficient and durable RuO 2 -based catalysts.
研究领域:
材料科学
·
电化学
✓ 已验证
产品关联
DOI
高影响因子
Journal of Materials Chemistry B
·
2021
·Vol. 9
·期 4
·992-1001
·
IF 6.331
Zihang Shen,Kaiyue Liu,Zheng Zhou,Qifang Li
This study proposes a simple method to prepare a pH-responsive and shape memory hydrogel based on cooperative hydrophobic interaction and hydrogen bonding. Acryloyl 11-aminoundecanoic acid (A11AUA) and acrylamide were selected as hydrophobic monomers and hydrophilic monomers, respectively. The mechanical properties of the prepared hydrogel strongly depend on the pH. Under acidic conditions, the maximum tensile strength of the hydrogel can reach 7.8 MPa, and the tensile modulus of the hydrogel can be increased by more than 10 000 times. The mechanical properties of acidic gels are affected by temperature and exhibit a temperature-controlled shape memory function. The acidic gel is immersed in NaOH and HCl solutions in sequence to achieve the function of reprogramming. Hydrogels under alkaline and neutral conditions exhibit conductivity and adhesion properties controlled by pH. Using the hydrogel as an adhesive electrode, the performance of the hydrogel in monitoring human electrophysiological signals was discussed.
研究领域:
材料科学
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生物医学工程
·
生物材料
✓ 已验证
产品关联
DOI
PubMed
高影响因子
EUROPEAN JOURNAL OF PHARMACEUTICS AND BIOPHARMACEUTICS
·
2018
·
IF 4.491
Huaihong Zhang,Yu Sun,Rong Huang,Hui Cang,Zhaosheng Cai,Baiwang Sun
Combination of chemotherapy with photothermal therapy (PTT) demonstrate highly desirable for efficient medical treatment of tumor. At present works, camptothecin (CPT)-containing polymeric prodrug (PCPT) were fabricated by polymerization of a pH-sensitive camptothecin (CPT) prodrug monomer and MPC using reversible addition-fragmentation transfer (RAFT) strategy. The pH-sensitive polymeric prodrug was tethered onto surface of polydopamine (PDA) nanoparticles by amidation chemistry for combination of chemotherapy with photothermal therapy. Specifically, the active CPT quickly released from the multifunctional nanoparticles in acidic microenvironment ascribe to the cleavage of bifunctional silyl ether linkage. Meanwhile, the PDA could convert the near infrared (NIR) light energy into heat with high efficiency, which makes the resulted nanoparticles an effective platform for photothermal therapy. In vitro analysis confirmed that the PDA@PCPT nanoparticles could be efficiently uptaked by HeLa cells and deliver CPT into the nuclei of cancer cells. The cell viability assays indicated an evident in vitro cytotoxicity to HeLa cancer cells under 808 nm light irradiation. Significant tumor regression was also observed in the tumor-bearing mice model with the combinational therapy provided from the PDA@PCPT nanoparticles. The PDA@PCPT multifunctional system which was achieved by a facile route should be a potential candidate in the anti-cancer field due to the synergistic therapeutic effect, which is superior to any single approach.
研究领域:
肿瘤学
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纳米医学
·
药物递送
✓ 已验证
产品关联
DOI
PubMed
高影响因子
Materials Science & Engineering C-Materials for Biological Applications
·
2015
·
IF 3.088
Na Cao,Miao Li,Yanbao Zhao,Li Qiu,Xueyan Zou,Yu Zhang,Lei Sun
To create novel nanocarriers for achieving excellent drug delivery performance, pH-responsive fluorescent porous silica (PS) nanocarriers were developed by encapsulating SnO 2 nanoparticles and coating polyethyleneimine (PEI) layer. SnO 2 /porous silica (SnO 2 /PS) nanoparticles have an average diameter of 80 nm and center-radial large pore channels. The large channels endow them high surface area with a Brunauer–Emmett–Teller (BET) area of 939 m 2 g − 1 . Aspirin was used as test drug to evaluate the releasing behavior of SnO 2 /porous silica/polyethyleneimine (SnO 2 /PS/PEI) nanoparticles. Results indicated that aspirin can be successfully incorporated into the SnO 2 /PS/PEI nanoparticles and the SnO 2 /PS/PEI nanoparticles displayed excellent pH-responsive release. The release rate in pH 7.4 buffer is higher than that in pH 5.5 buffer, which attributed to the PEI structure change in varied pH buffer. In addition, the SnO 2 /PS/PEI nanoparticles presented novel drug-dependent fluorescence, which could be used to trace the drug release.
研究领域:
材料科学
·
药学
·
纳米技术
✓ 已验证
DOI
PubMed
高影响因子
CHEMICAL ENGINEERING JOURNAL
·
2017
·
IF 6.216
Jiru Jia,Chaoxia Wang,Kunlin Chen,Yunjie Yin
To achieve pH-controlled drug release, a drug-loaded yolk/shell structured microcapsule with poly(DEAEMA-Styrene) (PDS) as yolk and polystyrene as shell was prepared by an all-in-one method of solvent evaporation and emulsion polymerization. The as-prepared microcapsule, in which the yolk swelled through the PDS pH-sensitive tertiary amino protonation and hydrophobic-to-hydrophilic transition, triggered the drug releasing via controlling the pH value. The yolk-swell microcapsule exhibited a non-swelling morphology in acidic solution to avoid extra drug diffusion. In the case of the pH value decreased from 7.5 to 3.4, there was a noticeable increase in the visible light transmittance of the PDS solution. In addition, the PDS swelling ratio increased from 10.7 to 5.8 as the value decreased from 5.3 to 3.4. The amounts of cumulative drug release were found to be 4-fold and 7-fold higher at pH 3.4 and 5.3, respectively, than that at pH 7.5, which demonstrated excellent pH response of the microcapsules. The unique yolk-swell strategy in this work sets a stage for an effective pathway in controllable drug delivery.
研究领域:
材料科学
·
药学
✓ 已验证
产品关联
DOI
高影响因子
危险品化学品经营许可证（带存储）