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Electrical Conductivity and pH Sensitivity of Ordered Porous Gel Acrylate Polymer Membrane with Nano-PANI Doping
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作者 Jie Zhao Ning Li 《Journal of Harbin Institute of Technology(New Series)》 EI CAS 2017年第2期65-71,共7页
Electrical conductivity and pH sensitivity of nano-PANI membrane was studied. In this work,an ordered porous nano-polyaniline/acrylate gel polymer( PAGP) membrane was prepared from methyl methacrylate( MMA)/acrylic ac... Electrical conductivity and pH sensitivity of nano-PANI membrane was studied. In this work,an ordered porous nano-polyaniline/acrylate gel polymer( PAGP) membrane was prepared from methyl methacrylate( MMA)/acrylic acid( AA)/nano-PANI bicontinuous microemulsions. The morphology,electric conductivity and p H sensitivity of the composite membrane were studied using scanning electronic microscopy,atomic force microscopy,and electrochemical impedance spectroscopy. It was found that the polymer matrix comprises of two types of proton migrating tunnels: interconnect hydrophilic trench( IHT) and continuous amphiphilic matrix( CAM). The increase of doped nano-PANI particles in those channels leads to a formation of three dimension grain-boundary network. It contributes to the short response time and good reversibility of the sensors. Impedance changes in the low-frequency region reveal an inductive behavior to PANI membrane,which maybe the contribution of faradaic pseudocapacitance of the polymer materials. 展开更多
关键词 nano-PANI porous structure migrating tunnels inductive behavior ph sensitivity
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Synthesis and Charcterization of Silane Crosslinked Hydrogel to pH Sensitive Study
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作者 Muhammad Awais Shahid Abdul Haseeb Tahir +1 位作者 Zeeshan Ahmad Muhammad Arslan 《American Journal of Analytical Chemistry》 CAS 2024年第5期165-176,共12页
Eco-friendly and biodegradable novel hydrogel were prepared by blending and solution casting method. The designed hydrogel is based on chitosan/ PEG600/Gurgam with carbon nanofiller along silane crosslinked (TEOS) wit... Eco-friendly and biodegradable novel hydrogel were prepared by blending and solution casting method. The designed hydrogel is based on chitosan/ PEG600/Gurgam with carbon nanofiller along silane crosslinked (TEOS) with pH sensitive response to controlled release of drug in biomedical materials and agriculture industry. The various concentration of carbon nanofiller is used to analyze its effect on the fabricated hydrogel characteristics by using FTIR, SEM, TGA, swelling studies (water, buffer and ionic solution). Spectra of FTIR reflected both established and newly developed groups (like hydrogel). COOH group presence is clearly observed in this range in the carbon filler reinforced hydrogel. The SEM micrographs show that CPG0.003 had a collection of polysaccharide chains as thin helices, which is attributed to the increase in the size of porosity. TGA shows to increase concentration of nanofiller enhanced the thermal stability of the designed hydrogels at temperature 25˚C to 550˚C mass loss percentage decrease upto 20% and increase thermal stability. This pH response made these resultant hydrogels as fruitful competitor against the many reported controlled release application. 展开更多
关键词 CHITOSAN Guargum HYDROGEL Carbon Nano Filler Silane Cross Linker ph Sensitive
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Docetaxel-loaded liposomes: preparation, pH sensitivity,Pharmacokinetics, and tissue distribution 被引量:5
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作者 Hong ZHANG Rui-ying LI +2 位作者 Xia LU Zhen-zhen MOU Gui-mei LIN 《Journal of Zhejiang University-Science B(Biomedicine & Biotechnology)》 SCIE CAS CSCD 2012年第12期981-989,共9页
Docetaxel (DTX), as a member of taxoid family, has been widely used in the treatment of cancers. The present study prepared pH-sensitive DTX-loaded liposomes (DTX-Lips) by thin-film dispersion method and various physi... Docetaxel (DTX), as a member of taxoid family, has been widely used in the treatment of cancers. The present study prepared pH-sensitive DTX-loaded liposomes (DTX-Lips) by thin-film dispersion method and various physico-chemical and morphological properties were examined. The pH sensitivity of in vitro DTX release and the in vivo pharmacokinetics and tissue distribution using Kunming mice were also investigated. The mean particle size and zetapotential of DTX liposomes were (277±2) nm and (-32.60±0.26) mV, respectively. Additionally, in vitro drug release study showed that the cumulative release rate was 1.3 times more at pH 5.0 than at pH 7.4, suggesting a pH-dependent releaseability of DTX-Lips. Pharmacokinetic and pharmaceutical studies in comparison with Duopafei showed that the half-timeperiod (t1/2) and area under the curve (AUC) of DTX-Lips in mouse plasma were 1.8 times longer and 2.6 times higher,respectively, and that DTX-Lips selectively accumulated in macrophage-rich organs such as liver and spleen. The seresults together suggest that the DTX-Lips could be a promising formulation for the clinical administration of DTX. 展开更多
关键词 Docetaxel-loaded liposomes ph sensitivity phARMACOKINETICS Tissue distribution
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Synthesis, Self-assembly and pH Sensitivity of a Novel Fluorinated Triphilic Block Copolymer 被引量:4
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作者 李欣欣 Xiao Huo +1 位作者 Hui-jiao Han 林绍梁 《Chinese Journal of Polymer Science》 SCIE CAS CSCD 2017年第11期1363-1372,共10页
A novel fluorinated triblock copolymer incorporating 2-ethylhexyl methacrylate (EHMA), tert-butyl methacrylate (tBMA) and 1H,1H,2H,2H-perfluorodecyl acrylate (FA) (PEHMA-b-PtBMA-b-PFA) was first synthesized us... A novel fluorinated triblock copolymer incorporating 2-ethylhexyl methacrylate (EHMA), tert-butyl methacrylate (tBMA) and 1H,1H,2H,2H-perfluorodecyl acrylate (FA) (PEHMA-b-PtBMA-b-PFA) was first synthesized using three successive reversible addition fragmentation chain transfer (RAFT) polymerization and the subsequent hydrolyzing at acidic condition. The as-fabricated triblock copolymer exhibited an interesting morphology evolution from the multi-compartment rod-like structure to spherical structure along with the addition of a selective solution. At the same time, a visible phase separation domain could be seen in the core area due to the existence of fluorocarbon segments. Furthermore, the self- assembly behavior of the triphilic copolymer at different pH was also verified by transmission electron microscopy, as well as the dynamic light scattering. These stimuli-responsive multi-compartment nanostructures may have potential applications in drug delivery. 展开更多
关键词 Triphilic block copolymer SELF-ASSEMBLY ph sensitivity Fluorinated copolymer Multi-compartment structure
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pH-triggered dynamic erosive small molecule chlorambucil nano-prodrugs mediate robust oral chemotherapy
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作者 Xin Liu Zhexiang Wang +6 位作者 Xiaodie Ren Xinyang Chen Jinjin Tao Yuanhui Guan Xuefeng Yang Rupei Tang Guoqing Yan 《Asian Journal of Pharmaceutical Sciences》 SCIE CAS 2023年第4期142-152,共11页
Currently,the dynamic erosive small molecule nano-prodrug is of great demand for oral chemotherapy,owing to its precise structure,high drug loading and improved oral bioavailability via overcoming various physiologic ... Currently,the dynamic erosive small molecule nano-prodrug is of great demand for oral chemotherapy,owing to its precise structure,high drug loading and improved oral bioavailability via overcoming various physiologic barriers in gastrointestinal tract,blood circulation and tumor tissues compared to other oral nanomedicines.Herein,this work highlights the successful development of pH-triggered dynamic erosive small molecule nano-prodrugs based on in vivo significant pH changes,which are synthesized via amide reaction between chlorambucil and star-shaped ortho esters.The precise nano-prodrugs exhibit extraordinarily high drug loading(68.16%),electric neutrality,strong hydrophobicity,and dynamic large-to-small size transition from gastrointestinal pH to tumoral pH.These favorable physicochemical properties can effectively facilitate gastrointestinal absorption,blood circulation stability,tumor accumulation,cellular uptake,and cytotoxicity,therefore achieving high oral relative bioavailability(358.72%)and significant tumor growth inhibition while decreasing side effects.Thus,this work may open a new avenue for robust oral chemotherapy attractive for clinical translation. 展开更多
关键词 Nano-prodrugs ph sensitivity Size transition Oral chemotherapy
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5-Fluorouracil-loaded Self-assembled pH-sensitive Nanoparticles as Novel Drug Carrier for Treatment of Malignant Tumors 被引量:7
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作者 刘亮 晋平 +2 位作者 程明 张国亮 张凤宝 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2006年第3期377-382,共6页
In order to improve the cancer-targeting and selective activity of antineoplastic agent [5-fluorouracil (5-FU)], a novel pH-responsive drug delivery system [pullulan acetate/sulfonamide (PA/SDM) conjugate] was syn... In order to improve the cancer-targeting and selective activity of antineoplastic agent [5-fluorouracil (5-FU)], a novel pH-responsive drug delivery system [pullulan acetate/sulfonamide (PA/SDM) conjugate] was synthesized by a diafiltration method. Sulfonamide was grafted to the hydrophobicaUy modified pullulan acetate to enhance the pH sensitivity for better cancer-targeting delivery. 5-FU was loaded into the self-assembled nanoparticles by the same method. The drug-loaded self-assembled nanoparticles were successfully obtained and characterized in terms of particle size, morphology and drug loading and release profile at various pHs. The results showed that the mean diameter of the self-assembled particles was approximately 100nm, with uniform size and good spherical morphology. The nanoparticles showed good stability at pH 7.4, which is equal to that of the normal body fluid, but shrank and aggregated below pH 6.8, which is close to the pH with tumors. The loading efficiency and concentration of released 5-FU was monitored at 269 nm on the UVNis spectrophotometer. The release profile was heavily pH-dependent around phvsiological pH, and the release rate was significantly enhanced under pH of 6.8. 展开更多
关键词 5-FLUOROURACIL self-assembled nanoparticles ph sensitivity drug delivery PULLULAN
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Synthesis and Characterization of Novel Temperature and pH Responsive Hydroxylpropyl Cellulose-based Graft Copolymers 被引量:3
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作者 李小军 尹明辉 +1 位作者 张国亮 张凤宝 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2009年第1期145-149,共5页
In this study, double-hydrophilic hydroxylpropyl cellulose (HPC) based copolymers with poly(N- isopropylacrylamide) (PNIPAM) and poly(acrylic acid) (PAA) as graft chains were synthesized and characterized. T... In this study, double-hydrophilic hydroxylpropyl cellulose (HPC) based copolymers with poly(N- isopropylacrylamide) (PNIPAM) and poly(acrylic acid) (PAA) as graft chains were synthesized and characterized. The release behavior of drug-loaded micelles was studied. The results show that the hydrophilicity of copolymers improves as the pH increases, whereas the hydrophobicity of copolymers enhances as the temperature increases, and all the phase behaviors are reversible. The diameter of micelles decreases and then increases with pH increase. It shows different micellizing behavior under acidic and basic conditions according to the temperature increase. In vitro release experiments, which used theophylline as a model drug, show that the micelles enhance pH sensitivity in the release process. 展开更多
关键词 hydroxylpropyl cellulose THERMOSENSITIVE ph sensitive MICELLE THEOphYLLINE
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Thermoreversible Thickening and Self-assembly Behaviors of pH/Temperature Dually Responsive Microgels with Interpenetrating Polymer Network Structure 被引量:1
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作者 刘晓云 杨军 +1 位作者 闫伟霞 査刘生 《Journal of Donghua University(English Edition)》 EI CAS 2014年第3期312-315,共4页
The pH /temperature dually responsive microgels of interpenetrating polymer network( IPN) structure composed of poly( N-isopropylacrylamide)( PNIPAM) network and poly( acrylic acid)( PAA) network( PNIPAM /PAA IPN micr... The pH /temperature dually responsive microgels of interpenetrating polymer network( IPN) structure composed of poly( N-isopropylacrylamide)( PNIPAM) network and poly( acrylic acid)( PAA) network( PNIPAM /PAA IPN microgels) were synthesized by seed emulsion polymerization. The results obtained by dynamic laser light scattering( DLLS) show that the microgels have good pH /temperature dual sensitivities. The temperature sensitive component and the pH sensitive component inside the microgels have little interference with each other. The rheological properties of the concentrated PNIPAM /PAA IPN microgel dispersions as a function of temperature at pH 4. 0 or 7. 0 were investigated by viscometer,and the results displayed that only at pH 7. 0 the dispersions presented thermoreversible thickening behavior. Then the PNIPAM /PAA fibers were prepared by self-assembly of the PNIPAM /PAA IPN microgels in the ice-crystal templates formed by unidirectional liquid nitrogen freezing method. Field emission scanning electron microscopy( FESEM) images indicate that the PNIPAM /PAA fibers are rounded,randomly orientated and interweaved. 展开更多
关键词 interpenetrating polymer network(IPN) structure ph and temperature sensitivity thermo-thickening self-assembly
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Synthesis and Characterization of Chitosan-Albumin Conjugates as pH-Sensitive Biodegradable Hydrogels
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作者 GUO Jin-shan LI Jian-zheng +2 位作者 JING Xia-bin CHEN Xue-si HUANG Yu-bin 《Chemical Research in Chinese Universities》 SCIE CAS CSCD 2011年第2期329-333,共5页
A new kind of biodegradable pH-sensitive drug delivery system was developed via chitosan-albumin conjugate hydrogel. Through changing the feeding modes of reactants, two types of hydrogels(comb-type and reticular-typ... A new kind of biodegradable pH-sensitive drug delivery system was developed via chitosan-albumin conjugate hydrogel. Through changing the feeding modes of reactants, two types of hydrogels(comb-type and reticular-type) were synthesized by amidation reactions between 6-O-succinoylated N-phthaloyl chitosan and albumin. The structures and morphologies of the hydrogels were characterized by SEM. And their water swelling capacity, drug loading and releasing properties at different pH values were also investigated. It was found that the comb-type of hydrogels with looser space construction had better water swelling ratio(more than 400% of its original mass) than the reticular-type of ones did(about 180% of its original mass). In vitro release experiments of Rifampicin show that the hydrogels provided the controlled release of the entrapped drug for more than 50 h. The drug release rates of both types of hydrogels under acidic condition were lower than those under neutral or basic condition. The introduction of albumin not only improved the hydrophilicity of chitosan, but also provided the possibility of the carrier system combining other biologically active materials more easily to fulfill the delivery and therapy functions. 展开更多
关键词 CHITOSAN ALBUMIN HYDROGEL ph Sensitive Drug delivery
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DESWELLING BEHAVIOR OF POLY(TETRAETHYLENEPENTAMINE EPICHLOROHYDRIN)GELS HYDROPHOBICALLY MODIFIED BY STEARIC ACID
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作者 杨亚江 《Chinese Journal of Polymer Science》 SCIE CAS CSCD 1999年第5期423-427,共5页
A novel type of polysoap hydrogel based on poly(tetraethylenepentamine-epichlorohydrin)hydrophobically modified by stearic acid was prepared. The deswelling behaviors of polysoap hydrogels werestudied by immersing the... A novel type of polysoap hydrogel based on poly(tetraethylenepentamine-epichlorohydrin)hydrophobically modified by stearic acid was prepared. The deswelling behaviors of polysoap hydrogels werestudied by immersing the gels in buffer solution at various pHs and ionic species. The deswelling of the gelsdid not depend on the cationic species of electrolyte but depended strongly on the anionic species. Acomparison of polysoap gels with the gel unmodified hydrophobically verified the importance of hydrophobicinteraction, which enhances the occurrence of deswelling rate. 展开更多
关键词 ph Sensitive Polysoap hydrogel Deswelling Ionic strength
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Preparation and Characterization of pH-Sensitive Polyvinyl Alcohol Hydrogel for Cancer Therapy
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作者 尹郅祺 冯炜 +2 位作者 陈梦霞 贾亚听 何创龙 《Journal of Donghua University(English Edition)》 EI CAS 2014年第4期530-532,共3页
Hydrogel has emerged as an excellent carrier platform for smart drug delivery and effective cancer treatment due to its high water content, good biocompatibility and sufficient mechanical properties. In this work,the ... Hydrogel has emerged as an excellent carrier platform for smart drug delivery and effective cancer treatment due to its high water content, good biocompatibility and sufficient mechanical properties. In this work,the DOX-loaded polyvinyl alcohol( PVA)hydrogel was prepared by freeze-thawing technique. The swelling test and the mechanical properties of the pure PVA hydrogels were performed. In addition, the in vitro drug release profiles were examined and the in vitro antitumor efficiency against He La cells was also estimated. The results indicated that the resulting PVA hydrogels contained significant amounts of water and possessed good mechanical properties,and DOX-loaded PVA hydrogel exhibited a sustained and p H-responsive DOX release. The MTT assays also demonstrated that the released DOX could effectively inhibit the proliferation of He La cells. Thus,the cross-linked PVA hydrogel can be further developed as a promising platform for cancer therapy. 展开更多
关键词 polyvinyl alcohol(PVA) hydrogels ph sensitive controlled drug release
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Equilibrium Swelling and Solute Diffusion Characteristics of Poly (Methacrylic Acid co-Poloxamer) Hydrogels 被引量:1
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作者 徐晖 丁平田 +2 位作者 魏刚 周贵生 郑俊民 《Journal of Chinese Pharmaceutical Sciences》 CAS 2001年第4期203-207,共5页
Poly(methacrylic acid co-poloxamer) hydrogel networks were synthesized by free radical solution polymerization and their equilibrium swelling and solute permeation properties were characterized. These gels exhibited p... Poly(methacrylic acid co-poloxamer) hydrogel networks were synthesized by free radical solution polymerization and their equilibrium swelling and solute permeation properties were characterized. These gels exhibited pH dependant swelling and solute diffusivity due to the formation or disruption of hydrogen bonded complexation between methacrylic acid (MAA) and etheric (EO). In neutral and basic conditions (above the swelling transition pH), the copolymer swelling was greatly higher than acid condition. In complexed hydrogels, the diffusion coefficients of vitamin B12 (VB12) were in the range of 10-10 to 10-7 cm2s-1; While in uncomplexed hydrogels, the values were about 210-6 cm2s-1. The comonomer composition and synthesis conditions have great effect on the structure, and thereby, swelling and solute diffusion characteristics of the resultant hydrogels. For the copolymers with composition of less than or more than 1:1 MAA/EO molar ratio, the plot of lnD vs 1/H-1 followed two different linear equations of 慺ree volume theory? respectively. 展开更多
关键词 Methacrylic acid POLOXAMER ph Sensitive hydrogel Equilibrium swelling Solute diffusion Free volume theory
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Poly(N-isopropylacrylamide), Poly(methacrylic acid) and Their Copolymers for Oral Colon-specific Drug Delivery 被引量:3
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作者 高玉香 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS 2009年第4期571-574,共4页
A series of cross-linked gels of Poly(N-isopropylacrylamide) [P(NIPAAm)] and Poly(methacr-ylic acid)[P(MAA)] homopolymers and P(NIPAAm-co-MAA) random copolymers were synthesized based on NIPAAm and MAA using... A series of cross-linked gels of Poly(N-isopropylacrylamide) [P(NIPAAm)] and Poly(methacr-ylic acid)[P(MAA)] homopolymers and P(NIPAAm-co-MAA) random copolymers were synthesized based on NIPAAm and MAA using 4,4-Bis-(methacryloylamino) azobenzene (BMAAB) as a cross-linker. The swelling behavior of these hydrogels in different pH buffer solutions was studied. The influential factors of the gels including composition of NIPAAm and MAA, pH and temperature upon swelling behavior were investigated. The obtained gels not only hold pH and thermometrical sensitivity, but also take on enzymatic sensitivity due to the cross-linker could be degraded by enzymes of colon. Swelling equilibrium degree of copolymers was very low in acidic medium, which could avoid drug releasing due to biggish swelling of carder in stomach. Hydrogels would partly swell owing to higher pH value in small intestine. When arrived in colon, hydrogels completely swelled, meanwhile, azoenzymes located would degrade azo-bonds of polymeric network and then drug released in colon. 展开更多
关键词 ph sensitivity therrnometrical sensitivity COLON-SPECIFIC
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Study on the Carbon Nanotube Separative Structure for the Extended Gate H^+-Ion Sensitive Field Effect Transistor 被引量:1
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作者 Yi-Hung Liao Jung-Chuan Chou 《稀有金属材料与工程》 SCIE EI CAS CSCD 北大核心 2006年第A03期225-227,共3页
We use the carbon nanotube (CNT) as the material of the pH sensing layer of the separative structure for the extended gate H^+-ion sensitive field effect transistor (EGFET) device.The CNT paste was prepared with CNT p... We use the carbon nanotube (CNT) as the material of the pH sensing layer of the separative structure for the extended gate H^+-ion sensitive field effect transistor (EGFET) device.The CNT paste was prepared with CNT powder,Ag powder,silicagel,the di-n-butyl phthalate and the toluene solvents by appropriate ratio,then immobilized on the silicon substrate to form the carbon nanotube sensing layer.We measured theⅠ_(DS)-Ⅴ_G curves of the carbon nanotube separative structure EGFET device in the different pH buffer solutions by the Keithley 236Ⅰ-Ⅴmeasurement system.According to the experimental results,we can obtain the pH sensitivities of the carbon nanotube separative structure EGFET device,which is 62.54mV/pH from pH1 to pH13. 展开更多
关键词 carbon nanotube extended gate field effect transistor ph sensitivity buffer solution
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Chitosan-g-PAA Hydrogels for Colon-Specific Drug Delivery: Preparation, Swelling Behavior and in vitro Degradability
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作者 龚时琼 殷以华 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS 2010年第2期248-251,共4页
A series of cross-linked hydrogels for colon-specific drug delivery were synthesized by graft copolymerization of Chitosan and acrylic acid using N, N'-methylene-bis-(acrylamide) as a cross-linker. Their swelling b... A series of cross-linked hydrogels for colon-specific drug delivery were synthesized by graft copolymerization of Chitosan and acrylic acid using N, N'-methylene-bis-(acrylamide) as a cross-linker. Their swelling behavior in different pH buffer solutions and colonic enzymatic degradability were studied. The obtained results show that these hydrogels have good pH sensitivity which can avoid drug release in stomach, and their swelling kinetics in stimulant intestinal environment follow second-order swelling kinetics equation. The factors influencing the swelling kinetics include the degree of cross-linking and the composition, which may control no release or a little amount release of drug inside the hydrogels in the small intestine by tailoring these factors. The gels are degradable by colonic enzymes and there is a correlativity between the degradation of networks and the swelling degree of the gels, which may trigger the release of drug in the colon. The hydrogels show a great potential for their application in oral colon-specific drug delivery system. 展开更多
关键词 HYDROGEL ph sensitivity swelling behavior colonic enzymatic degradability colon-specific drug delivery
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Assembly of a highly stable luminescent Zn5 cluster and application to bio-imaging
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作者 Ze-hui LIU Jin HUANG +1 位作者 Ming-hua ZENG Zheng YIN 《中国药理学与毒理学杂志》 CAS CSCD 北大核心 2017年第10期1022-1022,共1页
OBJECTIVE To explore a novel pH-sensitive fluorescent probe for in vivo tumor imaging.METHODS Zn5 were obtained in 140℃ after mixed with Me OH,water,Zn(NO_3)2·6 H_2O,H4L and trimethylamine.The fluorescence spect... OBJECTIVE To explore a novel pH-sensitive fluorescent probe for in vivo tumor imaging.METHODS Zn5 were obtained in 140℃ after mixed with Me OH,water,Zn(NO_3)2·6 H_2O,H4L and trimethylamine.The fluorescence spectra of Zn5 with the same concentration in different pH aqueous solutions were detected.And the stability of Zn5 was investigated by time dependent fluorescence emission spectra of Zn5 in BSA aqueous solution and 5.0% serum solution.Then,the cytotoxicity of Zn5 was detected by MTT assays.To clarify whether a similar fluorescence response occurs in biological organisms,He La cells were pretreated with probe Zn5(0.5 μmol·L^(-1)) and fluorescence imaging were collected for targeting lysosomes in living cells because of lysosomes′ acidic microenvironment.The A375 tumor-bearing mice were used to assess the imaging ability of Zn5 in vivo.Mouse tumor xenografts were established by injection of A375 cells with 2×10~6 cells per flank.Probe(1 μg·g^(-1)) was administered to mice by injection.Images were obtained using IVIS Spectrum CT Imaging System.RESULTS There is a 11-fold intensity increasing as the pH values changing from 8 to 2.The almost unchanged emission intensities suggest Zn5 is stable in both BSA and serum.Zn5 has negligible cytotoxicity for He La,293 T and CHO-K1 cells.Zn5 can selectively display lysosomes in living cells.Both the 2D and 3D images in vivo distinguish the tumor from other tissues with good fluorescence contrast.CONCLUSION The high chemical stability,emission in the Vis/NIR range,pH sensitivity,a pKa located in the tumor pH range,and low toxicity make Zn5 is suitable for application as a pH-sensitive fluorescent probe for bio-imaging. 展开更多
关键词 3d metal coordination cluster bio imaging fluorescence probes ph sensitivity Zn clusters
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Synthesis and Characterization of Poly(N-Vinyl-2-Pyrrolidone/Itaconic Acid) Hydrogel
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作者 郭锦棠 李伶 +1 位作者 李雄勇 刘冰 《Transactions of Tianjin University》 EI CAS 2004年第3期176-178,共3页
With N-vinyl-2-pyrrolidone (NVP) and itaconic acid(IA), poly(N-vinyl-2-pyrrolidone/itaconic acid)[P(NVP/IA)] hydrogel was synthesized by free radical solution polymerization. The structure of this (P(NVP/IA)) was char... With N-vinyl-2-pyrrolidone (NVP) and itaconic acid(IA), poly(N-vinyl-2-pyrrolidone/itaconic acid)[P(NVP/IA)] hydrogel was synthesized by free radical solution polymerization. The structure of this (P(NVP/IA)) was characterized by IR. Effects of concentration of itaconic acid, amount of cross-link agent, N,N′-methylene-bis-acrylamide, reaction temperature, and time on properties of swelling ratio(SR) of the hydrogel were investigated.The results show that the best swelling property of the hydrogel is obtained at 50 ℃ and 1.5 h. pH sensitivity increases as the concentration of itaconic acid in the hydrogel system increases. Swelling ratio of the hydrogel decreases as the amount of cross-link agent increases. 展开更多
关键词 HYDROGEL itaconic acid N-vinyl-2-pyrrolidone(NVP) ph sensitivity
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Synthesis and Properties of Poly (N-isopropylacrylamide) and Poly (N-isopropylacrylamide-co-acrylamide) Hydrogels
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作者 裴勇 陈捷 +2 位作者 杨黎明 施丽莉 罗浩杰 《Journal of Shanghai University(English Edition)》 CAS 2005年第5期466-470,共5页
The thermosensitive poly ( N-isopropylacrylamide ) (PNIPAAm) and poly (N-isopropylacrylamide-co-acrylamide) [ poly (NIPAAm-co-AAm) ] hydrogels with different acrylamide molar percentage are prepared by radiati... The thermosensitive poly ( N-isopropylacrylamide ) (PNIPAAm) and poly (N-isopropylacrylamide-co-acrylamide) [ poly (NIPAAm-co-AAm) ] hydrogels with different acrylamide molar percentage are prepared by radiation polymerization using Co^60 γ-ray. Their swelling equilibrium data in the media of deionized water, NaCl aqueous solutions and different pH buffer solutions are determined. It appears that lower critical solution temperature (LCST) of the hydrogels will drop with the increase of ionic strength and increase with the rising of acrylamide content, A semi-empirical formula is set up with the experimental results. Moreover, it also indicates that this copolymer is pH-sensitive, which is similar to the homopolymer of PNIPAAm. 展开更多
关键词 hydrogel lower critical solution temperature (LCST) poly (N-isopropylacrylamide) poly (N-isopropylacrylamide-co-acrylamide) ionic strength ph sensitive.
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Bi-doped carbon quantum dots functionalized liposomes with fluorescence visualization imaging for tumor diagnosis and treatment
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作者 Peide Zhu Yangjia Liu +8 位作者 Yaoyao Tang Siqi Zhu Xinyang Liu Lei Yin Quan Liu Zhiqiang Yu Quan Xu Dixian Luo Juncheng Wang 《Chinese Chemical Letters》 SCIE CAS CSCD 2024年第4期414-419,共6页
Liposomes are one of the significant classes of antitumor nanomaterials and the most successful nanomedicine drugs in clinical translation. However, it is difficult to accurately reveal liposome delivery modes and dru... Liposomes are one of the significant classes of antitumor nanomaterials and the most successful nanomedicine drugs in clinical translation. However, it is difficult to accurately reveal liposome delivery modes and drug release rates at different p H values to assess the biodistribution and drug delivery pathways in vivo. Here, we established a strategy to integrate Bi-doped carbon quantum dots(CQDs)with liposomes to produce fluorescence visualization and therapeutic effects, namely lipo/Bi-doped CQDs.Lipo/Bi-doped CQDs show good water solubility and physicochemical properties, which can be used for in vitro labeling of colon cancer(CT26) cells and in vivo imaging localization tracking tumors for monitoring. Simultaneously, thanks to the excellent p H sensitivity and ion doping characteristic of Bi-doped CQDs, lipo/Bi-doped CQDs can be used to reveal the drug release rate of liposomes at different p H values and exhibit potential effects in vivo antitumor therapy. 展开更多
关键词 Bi-doped CQDs Lipo/Bi-doped CQDs ph sensitivity In vitro/in vivo imaging Diagnosis and treatment integration
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Short and simple peptide-based pH-sensitive hydrogel for antitumor drug delivery 被引量:1
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作者 Jie Li Zhongshi Wang +6 位作者 Han Han Zhonghua Xu Shasha Li Ying Zhu Yuejian Chen Liang Ge Yuan Zhang 《Chinese Chemical Letters》 SCIE CAS CSCD 2022年第4期1936-1940,共5页
Since self-assembled peptide hydrogels can solve the problems such as low solubility, poor selectivity and serious adverse effects of traditional chemotherapy drugs, they have been widely used as carrier materials for... Since self-assembled peptide hydrogels can solve the problems such as low solubility, poor selectivity and serious adverse effects of traditional chemotherapy drugs, they have been widely used as carrier materials for drug delivery. In this study, we developed a novel and injectable drug delivery platform for the antitumor drug doxorubicin(DOX) using a p H-responsive ionic-complementary octapeptide FOE.This octapeptide could self-assemble into stable hydrogel under neutral conditions, while disassemble under the tumor microenvironment. Especially, at p H 5.8, its micromorphology displayed a transition from nanofibers to nanospheres with the change of secondary structure, which enhanced cellular uptake of DOX. In addition, FOE hydrogel serves as a smart drug reservoir by localized injection to achieve sustained drug release and improve antitumor efficacy. This octapeptide opens up new avenues for promoting the clinical translation of anticancer drugs on account of excellent injectable properties and economic benefits of simple and short sequence. 展开更多
关键词 Peptide hydrogel ph sensitivity ANTITUMOR Drug delivery Targeted therapy
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