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Dual-stimuli-sensitive poly(ortho ester disulfide urethanes)-based nanospheres with rapid intracellular drug release for enhanced chemotherapy

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Science China Chemistry 2018年第11期61卷 1447-1459页

作者： yan Huang Jiejie Qin Jun Wang guoqing yan Xin Wang Rupei Tang Engineering Research Center for Biomedical Materials Anhui Key Laboratory of Modern Biomanufacturing School of Life ScienceAnhui University

Herein, new poly（ortho ester disulfide urethanes）（POEDU） and poly（ortho ester urethanes）（POEU） were successfully syn- thesized via polycondensation between active esters of 1,6-hexandiol （HD） and dual-stimuli-sensitive ortho ester disulfide diamine or pH-senstive ortho ester diamine. The corresponding POEDU and POEU nanospheres were easily fabricated using an oil-in-water emulsion technique. In vitro degradation experiments indicated that POEDU nanospheres degraded faster than POEU nanospheres in mildly acidic and reductive environments. Doxorubicin （DOX） as a model antitumor drug was suc- cessfully incorporated into these nanospheres to give DOX-loaded nanoparticles （POEDU-DOX and POEU-DOX）. In vitro drug release studies showed that release of DOX from dual-stimuli-sensitive POEDU-DOX was accelerated compared with release from the pH-sensitive POEU-DOX under DL-dithiothreitol （DTT） and mildly acidic conditions. In addition, in vitro uptake and cytotoxicity assays revealed that POEDU-DOX exhibited more efficient antitnmor effect than POEU-DOX did against both two- dimensional （2D） cells and three-dimensional （3D） multicellular tumor spheroids （MCTS）. Finally, in a mice H22 tumor model, POEDU-DOX exhibited preferable antitumor capability. In conclusion, the pH and redox dual-stimuli-sensitive POEDU na- nospheres can be superior drug carriers for cancer treatment.

关键词： nanospheres ortho ester disulfide drug release antitumor

Porous Silicon Carbide/Carbon Composite Microspherules for Methane Storage

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Journal of Natural Gas Chemistry 2007年第4期16卷 363-370页

作者： Fengbo Li Qingli Qian Shufeng Zhang Fang yan guoqing Yuan Laboratory of New Materials Institute of Chemistry Chinese Academy of Sciences Beijing 100080 China

Porous silicon carbide/carbon （SiC/C） microspherules were prepared by the controlled heating treatment of polymer and silica hybrid precursors over 1000℃ in Ar/H2 stream. The resultant SiC/C composite shows improved physical properties such as excellent mechanical strength, regular physical form, and high packing density. Such improvement overcomes the main inherent problems encountered when using activated carbons as absorbents without sacrificing porosity properties. N2 sorption analysis shows that the SiC/C composite has a BET surface area of 1793 m^2/g and a pore volume of 0.92 ml/g. Methane adsorption isotherm is determined by the conventional volumetric method at 25℃ and up to 7.0 MPa. On volumetric basis, the SiC/C composite microspherules show methane storage of 145 （V/V） at 3.5 MPa and 25℃. The combination of excellent physical properties and porosity properties in this SiC/C composite lends a great possibility to develop a competitive storage system for natural gas.

关键词： carbides microporous materials energy storage

Dynamic micelles with detachable PEGylation at tumoral extracellular pH for enhanced chemotherapy

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Asian Journal of Pharmaceutical Sciences 2020年第6期15卷 728-738页

作者： guoqing yan Panpan Zhang Jun Wang Xin Wang Rupei Tang Engineering Research Centerfor Biomedical Materials School of Life ScienceAnhui UniversityHefei 230601China

Although surface PEGylation of nanomedicines can decrease serum protein adsorption in vivo,it also blocks uptake by tumor *** dilemma could be overcome by employing detachably PEGylated strategy at tumoral extracellular microenvironment to achieve improved cellular uptake while prolonged circulation ***,the amphiphilic graft copolymers with p H-sensitive ortho ester-linked m PEG in side chains and polyurethanes in backbone,can self-assemble into the free and doxorubicin(DOX)-loaded *** p H-sensitive micelles could undergo several characteristics as follows:(i)PEGylated shells for stability in sodium dodecyl sulfonate(SDS)solution;(ii)De PEGylation via degradation of ortho ester linkages at tumoral extracellular pH(6.5)for gradually dynamic size changes and effective release of DOX;and(iii)enhanced cellular uptake and cytotoxicity via positive ***,the dynamic micelles with detachable PEGylation could quickly penetrate the centers of SH-SY5 Y multicellular spheroids(MCs)and strongly inhibit tumor growth in vitro and in vivo,and might be considered as promising and effective drug carriers in tumor therapy.

关键词： Micelles Ortho ester PEGylation Size transition Antitumor

Low-field magnetoresistance of (1-x)La_(0.6)Dy_(0.1)Sr_(0.3)MnO_3/0.5x (Sb_2O_3) composite system under different sintering temperatures of matrix

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Rare Metals 2012年第3期31卷 276-280页

作者： yang, Jie yan, guoqing Wang, Guiying Tang, Yonggang Song, Qixiang Zhang, Mingyu Peng, Zhensheng Anhui Key Laboratory of Spintronic and Nanometric Materials Suzhou 234000 Anhui China School of Mechanical and Electronic Engineering Suzhou University Suzhou 234000 Anhui China Hefei National Laboratory for Physical Sciences at the Microscale University of Science and Technology of China Hefei 230026 China

A series of (1-x)La0.6Dy0.1Sr0.3MnO3/0.5x(Sb2O3)(x=0.15) samples were prepared by the solid-state reaction method, and the influence of sintering temperature of the matrix on low-field magnetoresistance of (1-x)La0.6Dy0.1Sr0.3MnO3/0.5x (Sb2O3) was studied through the measurements of X-ray diffraction (XRD) patterns, scanning electron microscope (SEM) image, resistivity-temperature (ρ-T) curves, and magnetoresistance-temperature (MR-T) curves. The results indicate that for the samples with low sintering temperature of the matrix, lowfield magnetoresistance effect appears on the whole temperature range and can be explained by grain boundary effect; for the sample with high sintering temperature of the matrix, intrinsic magnetoresistance peak appears on the high-temperature range, low-field magnetore-sistance effect appears on low temperature range, and the magnetoresistance in the magnetic field of 0.2 T and on the comparatively large temperature range between 280 K and 225 K hardly changes with temperature and remains at 4.8%, which can be explained by the competition between the intrinsic magnetoresistance induced by double-exchange function inside grains and the tunneling magnetoresis-tance (TMR) induced by grain boundary effect. The temperature stability of magnetoresistance is beneficial to the practical applications of MR.

关键词： low-field magnetoresistance two-phase composite sintering temperature of the matrix perovskite manganite

Research on charge ordering and magnetic properties in La_(0.3)Ca_(0.7)Mn_(1-x)W_xO_3 system

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Rare Metals 2007年第4期26卷 317-322页

作者： PENG Zhensheng GUO Huanyin yan guoqing MAO Qiang Physics Department Suzhou College Suzhou 234000 China Structure Research Laboratory University of Science and Technology of China Hefei 230026 China

The perovskite manganite sample La0.3Ca0.7Mn1-xWxO3 （x = 0.08, 0.12） was prepared by the solid-state reaction method. The effect of W doping on the Mn site to La0.3Ca0.7MnO3 charge ordering phase and the changing process of magnetic properties were studied through the measurement of the M-T curve, M-H curves, and ESR curves of the sample. The results showed that when x = 0.08, the charge ordering （CO） phase exists in the system, the transition temperature Tco= 275 K, and the system exhibits PM when T 〉 275 K. The system transforms from spin-disordering paramagnetism to spin-ordering antiferromagnetism in the charge ordering state with the temperature decreasing from 275 K to 230 K. The long-range antiferromagnetism forms and AFM/CO states coexist between 230 K and 5 K. There is a little ferromagnetic component in the AFM/CO background in a low temperature range. When x = 0.12, the CO phase in the system has almost melted completely. There is a little remnant of the CO phase below 150 K. The system exhibits paramagnetism when T 〉 150 K and transforms from paramagnetism to ferromagnetism when T〈 150 K.

关键词： condensed matter physics charge ordering melting solid-state reaction method magnetic properties

Magnetoresistance enhancement and temperature stability of magnetoresistance in La_(1-x)(Sr_(1-y)Na_y)_xMnO_3

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Rare Metals 2012年第4期31卷 387-391页

作者： Wang, Guiying yan, guoqing yang, Jie Wang, Wenqi Tang, Yonggang Song, Qixiang Zhang, Mingyu Peng, Zhensheng Anhui Key Laboratory of Spintronic and Nanometric Materials(Cultivating Base) Suzhou 234000China School of Mechanical and Electronic Engineering Suzhou UniversitySuzhou 234000China Hefei National Laboratory for Physical Sciences at the Microscale University of Science and Technology of ChinaHefei 230026China

A series of the samples La_(1-x)(Sr_(1-y)Na_y)_xMnO_3(y=0.0,0.2,0.4,0.6,0.8,1.0) were prepared by the solid-state reaction *** enhancement and temperature stability of magnetoresistance in the system La_(1-x)(Sr_(1-y)Na_y)_xMnO_3 with unchanged Mn^(3+)/Mn^(4+) ratio through the doping of both monovalent and divalent elements at A site were studied through the measurements of X-ray diffraction(XRD) patterns,resistivity-temperature(ρ-T) curves and magnetoresistance-temperature(MR-T) *** results indicate that with the increase of Na doping amount,the peak value of MR increases,and it increases from 12.4% for y=0.2 to 50.6% for y=1.0 in the magnetic field B=0.8 T;ρ-T curves exhibit the double-peak phenomenon,which comes from the competition between the resistivity of surface phase and that of body phase;for the sample of y=0.8,MR increases slowly from 8.3% to 9.4% in the temperature range from 259 to 179 K,and MR is so stable in such a wide temperature range,which provides reference for the research on the temperature stability of MR.

关键词： magnetoresistance enhancement temperature stability perovskite manganite

pH-sensitive micelles self-assembled from star-shaped TPGS copolymers with ortho ester linkages for enhanced MDR reversal and chemotherapy

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Asian Journal of Pharmaceutical Sciences 2021年第3期16卷 363-373页

作者： Yong Xu Shi Wang Longshun yang Yuhang Dong Yafang Zhang guoqing yan Rupei Tang Engineering Research Center for Biomedical Materials Anhui Key Laboratory of Modern BiomanufacturingSchool of Life SciencesAnhui UniversityHefei 230601China

TPGS approved by FDA can be used as a P-gp inhibitor to effectively reverse multi-drug resistance(MDR)and as an anticancer agent for synergistic antitumor ***,the comparatively high critical micelle concentration(CMC),low drug loading(DL)and poor tumor target limit its further clinical *** overcome these drawbacks,the pH-sensitive star-shaped TPGS copolymers were successfully constructed via using pentaerythritol as the initial materials,ortho esters as the pH-triggered linkages and TPGS active-ester as the terminated MDR *** amphiphilic star-shaped TPGS copolymers could self-assemble into free and doxorubicin(DOX)-loaded micelles at neutral aqueous *** micelles exhibited the lower CMC(8.2×10^(−5) mg/ml),higher DL(10.8%)and long-term storage and circulation stability,and showed enhanced cellular uptake,apoptosis,cytotoxicity,and growth inhibition for in vitro MCF-7/ADR and/or MCF-7/ADR multicellular spheroids and in vivo MCF-7/ADR tumors via efficiently targeted drug release at tumoral intracellular pH(5.0),MDR reversal of TPGS,and synergistic effect of DOX and ***,the pH-sensitive micelles self-assembled from star-shaped TPGS copolymers with ortho ester linkages are potentially useful to clinically transform for enhanced MDR cancer treatment.

关键词： TPGS Ortho esters Star-shaped copolymers MDR reversal

Charge order and spin orderof La_(0.3)Ca_(0.7)Mn_(1-x)W_(x)O_(3) system

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Chinese Science Bulletin 2006年第7期51卷 770-776页

作者： LIU Ning yan guoqing CAI Zhirang GUO Huanyin PENG Zhensheng QU Zhe ZHANG Yuheng Materials Research Laboratory Suzhou College Suzhou 234000 China Structure Research Laboratory University of Science and Technology of China Hefei 230026 China

The influences of W doping at Mn site on the charge order and spin order were studied by measuring M-T curves, M-H curves and ESR spectra of La0.3Ca0.7Mn1?xWxO3 (x = 0.00, 0.04, 0.08, 0.12, 0.15) system. The results showed that: When 0.00≤ x≤0.08, the system exhibits charge ordering (CO) phase, and its spin order experiences the change of paramagnetism (PM)-charge ordering (CO)-antiferro- magnetism (AFM) with decreasing temperature; when x≥0.12, the charge ordering (CO) phase melts, part of charge ordering (CO)phase remains in the paramagnetism (PM)background, the spin order of the system is mainly paramagnetism (PM), and ferromagnetic (FM) clusters appear at low tem- perature.

关键词： La0.3Ca0.7Mn(1-x)WxO3 稀土熔炼残渣炉料

Dynamic crosslinked polymeric nano-prodrugs for highly selective synergistic chemotherapy

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Asian Journal of Pharmaceutical Sciences 2022年第6期17卷 880-891页

作者： Shi Wang Yining Song Jingge Ma Xinyang Chen Yuanhui Guan Hui Peng guoqing yan Rupei Tang Engineering Research Center for Biomedical Materials Anhui Key Laboratory of Modern BiomanufacturingSchool of Life SciencesAnhui UniversityHefei 230601China Anhui Engineering Technology Research Center of Biochemical Pharmaceutical Bengbu Medical CollegeBengbu 233030China

To achieve highly selective synergistic chemotherapy attractive for clinical translation,the precise polymeric nano-prodrugs(PPD-NPs)were successfully constructed via the facile crosslinking reaction between p H-sensitive poly(ortho ester)s and reduction-sensitive small molecule synergistic prodrug(Pt(IV)-1).PPD-NPs endowed the defined structure and high drug loading of cisplatin and demethylcantharidin(DMC).Moreover,PPD-NPs exhibited steady long-term storage and circulation via the crosslinked structure,suitable negative potentials and low critical micelle concentration(CMC),improved selective tumour accumulation and cellular internalization via dynamic size transition and surficial amino protonation at tumoural extracellular p H,promoted efficient disintegration and drug release at tumoural intracellular p H/glutathione,and enhanced cytotoxicity via the synergistic effect between cisplatin and DMC with the feed ratio of 1:2,achieving significant tumour suppression while decreasing the side ***,the dynamic crosslinked polymeric nano-prodrugs exhibit tremendous potential for clinically targeted synergistic cancer therapy.

关键词： Nano-prodrugs Precise structure Size transition Amino protonation Synergistic chemotherapy