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Hydrogen-bonding regulated supramolecular chirality with controllable biostability

Nano Research 2022年第3期15卷 2226-2234页

作者： Jinying Liu Yu Zhao Changli Zhao Xiaoqiu Dou Xiaoyu Ma Shaokang Guan Yu Jia Chuanliang Feng State Key Lab of Metal Matrix Composites School of Materials Science and EngineeringShanghai Jiao Tong UniversityShanghai 200240China Key Laboratory for Special Functional Materials of Ministry of Education School of Materials Science and EngineeringHenan UniversityKaifeng 475004China School of Materials Science and Engineering Zhengzhou UniversityZhengzhou 450001China International Laboratory for Quantum Functional Materials of Henan and School of PhysicsZhengzhou UniversityZhengzhou 450001China

The regulation of natural helical nanostructures is principally supported and actuated by hydrogen bonds(H-bonds)formed from hydrogen-bonding groups(peptide bonds and base pairs)to realize biological activities and specific biofunctional ***,studying the role of H-bonding patterns on the handedness of supramolecular assemblies is still challenging,since supramolecular assemblies will be disassembled or destabilized with slightly varying H-bonding groups for most *** circumvent this issue,herein,two types of self-assembled C2-symmetric phenylalanine derivatives differed by a single H-bonding group(ester or amide)are systematically designed for deciphering the role of H-bonding pattern on the chirality of supramolecular assemblies and their related *** handedness nanofibrous structures with tailorable diameter and helical pitch are achieved with the transition from ester to amide groups in the *** and theoretical evidence suggests that helical orientation of ester-containing gelators ascribes to intermolecular *** contrast,the helical direction for the amide-counterparts is mainly due to intra-and intermolecular ***,these H-bonding groups greatly influence their stability,as revealed by in vitro and in vivo degradation experiments and the left-handed assemblies are more stable than the right-handed ***,the study offers a feasible model to have valuable insight into understanding the role of H-bonding patterns in biological folding.

关键词： supramolecular chirality helical structures hydrogen-bonding group hydrogen-bonding pattern biostability

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Molecular Tail-protection Design（MTD） Enhances Aptamers biostability in Tumor Microenvironment

Molecular Tail-protection Design（MTD） Enhances Aptamers Bi...

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第十一届全国化学生物学学术会议

作者： Sitao Xie Zhimin Wang Liyan Zheng Hui Wu Hailan Kuai Liping Qiu Weihong Tan Molecular Science and Biomedicine Laboratory State Key Laboratory of Chemo/Bio-Sensing and ChemometricsCollege of Chemistry and Chemical EngineeringCollege of BiologyCollaborative Innovation Center for Chemistry and Molecular MedicineHunan University

Aptamers with high affinity and specificity are powerful molecular tools in the fields of diagnostic and ***,natural aptamers are highly susceptible to nucleases degradation in vivo *** existing methods can improve the global biostability of aptamers via the introduction of modified nucleotides,aptamers are usually expected to function only in lesions area but useless in unappointed region from clinical ***,we report that the molecular tail-protection design（MTD） enhances the biostability of natural aptamers in the tumor *** MTD,a split ATP aptamer was separately embedded into both ends of targeted aptamers,termed MT-aptamers,which would bind to ATP molecules from the tumor microenvironment and thus resistant to nucleases *** stability,nuclease resistance and in vivo fluorescence imaging analysis of MT-aptamers showed that MT-aptamers biostability was significantly improved without compromising aptamer binding properties,specifically prolonging MT-aptamers circulation time in tumor ***,the universality of MTD was also verified by another three MT-aptamers ***,the MTD provides a simple and universal method to specifically enhance the biostability of natural aptamers without introducing any modified elements,accelerating the development of aptamer applications in vivo.

关键词： Aptamers biostability Nucleases degradation Tumor microenvironment

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Stimuli-responsive gel-micelles with flexible modulation of drug release for maximized antitumor efficacy

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Nano Research 2018年第8期11卷 4245-4264页

作者： Djamila Aouameur Hao Cheng Yaw Opoku-Damoah Bo Sun Qiuling Dong Yue Han Jianping Zhou Yang Ding State Key Laboratory of Natural Medicines Department of Pharmaceutics China Pharmaceutical University 24 TongjiaxiangNanjing 210009 China Department of Radiation Oncology Lineberger Comprehensive Cancer Center Carolina Center for Cancer NanotechnologyExcellence Carolina Institute of Nanomedicine University of North Carolina at Chapel Hill Chapel Hill NC27599 USA Djamila Aouameur and Hao Cheng contributed equally to this work.

Engineered stimuli-responsive drug delivery devices hold vast promise in biological applications for disease treatment due to their maximized therapeutic efficacy In this study a novel, stably cross-linked, and pH-sensitive biodegradable gel-micelle was constructed with amphiphilic conjugates of trimethylene dipiperidine- methacrylic anhydride-hyaluronic acid-stearylamine （TMDP-MA-HA-SA, TMHS） to improve tumor-targeting with flexible intracellular delivery of paditaxel （PTX）. The cross-linked methacrylate bonds significantly improved the biostability of TMHS gel-micelle （~ 200 nm） over the non-cross-linked under physiological conditions, while hyaluronic acid plays an important role in active tumor targetability. The gradual degradation of cross-linked hyaluronic acid shell was triggered by the concentrated hyaluronidase. Meanwhile, under acidic conditions （pH 〈 6.5）, the tertiary amines of pH-sensitive TMDP moieties were protonated and thereby solubilized the gel-micellar core-portions. The resultant pH-triggered inner-core spaces rapidly prompted PTX release in the presence of multiple cytosolic enzymes that mainly degraded the remaining hydrophobic stearylamine core. During the in vitro cytotoxicity assay, PTX-loaded TMHS gel-micelles （ct~） revealed anticancer efficacy against human hepatocellular carcinoma HepG2 cells with ICs0 of 1.42 gg/mL （PTX concentration）, significantly lower than other groups. In parallel, the in vivo anti-tumor efficacy of CLTMHSptx gel-micelles against BALB/c xenograft tumor animal model demonstrated the greater tumor growth inhibition capacity of 72.06%, compared to other treatment groups at a safe concentration. Consequently, the cross-linked and stimuli-responsive CLTMHSFrx gel-micelles hold a great potential for flexible modulation of intracellular delivery of hydrophobic anticancer drugs with maximized antitumor efficacy.

关键词： stimuli-responsive cross-linked gel-micelles biostability flexible drug release maximized antitumorefficacy

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Pilot plant study on ozonation and biological activated carbon process for drinking water treatment

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Journal of Environmental Sciences 2006年第2期18卷 232-235页

作者： KONG Ling-yu ZHANG Xiao-jian WANG Zhan-sheng Department of Environmental Science and Engineering Tsinghua University Beijing 100084 China

A study on advanced drinking water treatment was conducted in a pilot scale plant taking water from conventional treatment process. Ozonation-biological activated carbon process （O3-BAC） and granular activated carbon process （GAC） were evaluated based on the following parameters： CODMn, UV254, total organic carbon （TOC）, assimilable organic carbon （AOC） and biodegradable dissolved organic carbon （BDOC）. In this test, the average removal rates of CODMn, UV254 and TOC in O3-BAC were 18.2%, 9.0% and 10.2% higher on （AOC） than in GAC, respectively. Ozonation increased 19.3-57.6 μg Acetate-C/L in AOC-P17, 45.6-130.6 μg Acetate-C/L in AOC-NOX and 0.1-0.5 mg/L in BDOC with ozone doses of 2 8 mg/L. The optimum ozone dose for maximum AOC formation was 3 mgO3/L. BAC filtration was effective process to improve biostability.

关键词： ozonation biological activated carbon CODMn UV254 TOC AOC BDOC biostability

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Factors Affecting Bacterial Growth in Drinking Water Distribution System

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Biomedical and Environmental Sciences 2005年第2期18卷 137-140页

作者： WEILU XIAO-JIANZHANG DepartmentofEnvironmentalScienceandEngineering TsinghuaUniversityBeijing100084China

Objective To define the influence of some parameters, including assimilable organic carbon (AOC), chloramine residual, etc. on the bacterial growth in drinking water distribution systems. Methods Three typical water treatment plants in a northern city (City T) of China and their corresponding distribution systems were investigated. Some parameters of the water samples, such as heterotrophic plate content (HPC), AOC, CODMn, TOC, and phosphate were measured. Results The AOC in most water samples were more than 100 μg/L, or even more than 200 μg/L in some cases. The HPC in distribution systems increased significantly with the decrease of residual chlorine. When the residual chlorine was less than 0.1 mg/L, the magnitude order of HPC was 104 CFU/mL; when it was 0.5-0.7 mg/L, the HPC was about 500 CFU/mL. Conclusion For controlling the biostability of drinking water, the controlling of AOC and residual chlorine should be considered simultaneously. The influence of phosphors on the AOC tests of water is not significant. Phosphors may not be the limiting nutrient in the water distribution systems.

关键词： Drinking water AOC HPC Phosphors Residual chlorine biostability

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Structural Comportment of Extract of Bougainvillea xbuttiana Flower Incorporated in Silica Xerogel Matrix

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American Journal of Plant Sciences 2016年第6期7卷 828-833页

作者： José Martínez-Mendoza Erika Espericueta-González Diana Espericueta-González Gerardo Ortega-Zarzosa Azdrubal Lobo Guerrero Departamento de Físico-Matemáticas Universidad Autónoma de San Luis Potosí San Luis Potosí México Facultad de Ciencias Universidad Autónoma de San Luis Potosí San Luis Potosí México Facultad de Ingeniería Universidad Autónoma de San Luis Potosí San Luis Potosí México Doctorado Institucional de Ciencia e Ingeniería de Materiales Universidad Autónoma de San Luis Potosí San Luis Potosí México Instituto de Física Universidad Autónoma de San Luis Potosí San Luis Potosí México

Measurement of the fluorescence comportment of Bougainvillea xbuttiana flowers embedded in silica xerogels matrix prepared with two different water to tetraethyl-orthosilicate [Si(OC2H5)4] ratio molar of 11 and 5, without heat-treatment, we report the grade of biostability of compound. The structural comportment for the PSI and PSII present in Bougainvillea flower is similar to the structural comportment for these photosystems present in leaves when they are incorporated on inorganic matrix such as silica xerogels. The contribution of the natural pigment of this kind of flower such as betalains which consist of betaxanthins and betacyanins, determines their colors contributed in the range of wavelength from about 550 nm to 660 nm.

关键词： Betalaine Chlorophyll Structure biostability Sol-Gel

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Thermo-Stability of Natural Products Based on Chlorophyll Species Embedded in Silica Xerogel

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American Journal of Analytical Chemistry 2016年第4期7卷 356-362页

作者： José Martínez-Mendoza Erika Espericueta-González Diana Espericueta González Gerardo Ortega-Zarzosa Azdrubal Lobo Guerrero Departamento de Físico-Matemáticas Universidad Autónoma de San Luis Potosí San Luis Potosí México Facultad de Ciencias Universidad Autónoma de San Luis Potosí San Luis Potosí México Facultad de Ingeniería Universidad Autónoma de San Luis Potosí San Luis Potosí México Doctorado Institucional de Ciencia e Ingeniería de Materiales Universidad Autónoma de San Luis Potosí San Luis Potosí México Instituto de Física Universidad Autónoma de San Luis Potosí San Luis Potosí México

This work studied the thermostability and the biostability of chlorophyll species obtained from an extract of spinach leaves embedded in a silica xerogel matrix. The analysis was done by monitoring the photosystem II (PSII) using fluorescence spectroscopy. Samples were prepared using the sol gel method with a molar ratio of ethanol/H2O/TEOS of 4:11.6:1. Then, silica xerogel matrix was loaded with an extract of spinach leaves, obtained in dark conditions. The measurement of the fluorescence spectra was done at selected temperatures to the corresponding non-physiological regimen. Results indicate that the PSII band position remains unchanged when heat treatment temperature increases up 200°C. For temperatures above 100?C, the fluorescence intensity diminishes linearly when the temperature increases. The photosystem II embedded in silica xerogel matrix is decomposed at temperatures above 200°C.

关键词： Chlorophyll Structure biostability Sol-Gel

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