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Effects of silica nanoparticles on growth and photosynthetic pigment contents of Scenedesmus obliquus 被引量:16
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作者 Chenxi Wei, Yanbo Zhang, Jing Guo, Bing Han, Xu Yang, Junlin Yuan Hubei Key Laboratory of Genetic Regulation and Integrative Biology, College of Life Sciences, Huazhong Normal University, Wuhan 430079, China. 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2010年第1期155-160,共6页
To assess the aquatic ecosystem safety for silica (SiO2) nanoparticles (NPs), the growth inhibition and photosynthetic pigment contents of Scenedesmus obliquus in logarithm growth phase exposed to SiO2 NPs and SiO... To assess the aquatic ecosystem safety for silica (SiO2) nanoparticles (NPs), the growth inhibition and photosynthetic pigment contents of Scenedesmus obliquus in logarithm growth phase exposed to SiO2 NPs and SiO2 bulk particles (BPs) suspensions were measured. SiO2 NPs with 10-20 nm diameters were found to be toxic. The 20% effective concentration (EC20) values for 72 and 96 hr were 388.1 and 216.5 mg/L, respectively. The contents of chlorophyll decreased significantly under moderate and high concentration (50, 100, and 200 mg/L) of SiO2 NPs after 96-hr exposure, but the carotenoids did not. SiO2 BPs were found to be nontoxic up to 200 mg/L. The toxicity of SiO2 NPs probablely due to their sorption to algal cells surface. The results imply that there is potential harm to aquatic environment by using SiO2 NPs, and it should deserve special concern. 展开更多
关键词 photosynthetic pigment Scenedesmus obliquus silica nanoparticles
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pH-responsive mesoporous silica nanoparticles employed in controlled drug delivery systems for cancer treatment 被引量:8
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作者 Ke-Ni Yang Chun-Qiu Zhang +3 位作者 Wei Wang Paul C.Wang Jian-Ping Zhou Xing-Jie Liang 《Cancer Biology & Medicine》 SCIE CAS CSCD 2014年第1期34-43,共10页
In the fight against cancer, controlled drug delivery systems have emerged to enhance the therapeutic efficacy and safety of anti-cancer drugs. Among these systems, mesoporous silica nanoparticles (MSNs) with a func... In the fight against cancer, controlled drug delivery systems have emerged to enhance the therapeutic efficacy and safety of anti-cancer drugs. Among these systems, mesoporous silica nanoparticles (MSNs) with a functional surface possess obvious advantages and were thus rapidly developed for cancer treatment. Many stimuli-responsive materials, such as nanopartides, polymers, and inorganic materials, have been applied as caps and gatekeepers to control drug release from MSNs. This review presents an overview of the recent progress in the production of pH-responsive MSNs based on the pH gradient between normal tissues and the tumor microenvironment. Four main categories of gatekeepers can respond to acidic conditions. These categories will be described in detail. 展开更多
关键词 Mesoporous silica nanoparticles PH-RESPONSIVE controlled drug release drug delivery systems antineoplastic protocols
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Effect of silica nanoparticles/poly(vinylidene fluoride-hexafluoropropylene) coated layers on the performance of polypropylene separator for lithium-ion batteries 被引量:4
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作者 Hongyu Liu Zehui Dai +2 位作者 Jun Xu Baohua Guo Xiangming He 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2014年第5期582-586,共5页
In an effort to reduce thermal shrinkage and improve electrochemical performance of porous polypropylene (PP) separators for lithium-ion batteries, a new composite separator is developed by introducing ceramic coate... In an effort to reduce thermal shrinkage and improve electrochemical performance of porous polypropylene (PP) separators for lithium-ion batteries, a new composite separator is developed by introducing ceramic coated layers on both sides of PP separator through a dip-coating process. The coated layers are comprised of heat-resistant and hydrophilic silica nanoparticles and polyvinylidene fluoride-hexafluoropropylene (PVDF-HFP) binders. Highly porous honeycomb structure is formed and the thickness of the layer is only about 700 nm. In comparison to the pristine PP separator, the composite separator shows significant reduction in thermal shrinkage and improvement in liquid electrolyte uptake and ionic conduction, which play an important role in improving cell performance such as discharge capacity, C-rate capability, cycle performance and coulombic efficiency. 展开更多
关键词 composite separator silica nanoparticles DIP-COATING thermal shrinkage cell performance
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Determination of Sulfadimidine in Royal Jelly by C_(18)-functionalized Magnetic Silica Nanoparticles Solid Phase Extraction-High Performance Liquid Chromatography-Tandem Mass Spectrometry
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作者 李金峰 李颖 +3 位作者 蒋原 薛峰 戴劲 朱海 《Agricultural Science & Technology》 CAS 2012年第11期2278-2280,共3页
[Objective] This study aimed to develop a method of C_18-functionalized magnetic silica nanoparticles solid phase extraction-high performance liquid chro- matography-tandem mass spectrometry for the determination of s... [Objective] This study aimed to develop a method of C_18-functionalized magnetic silica nanoparticles solid phase extraction-high performance liquid chro- matography-tandem mass spectrometry for the determination of sulfadimidine in royal jelly. [Method] The royal jelly samples were pretreated by MCX SPE column and C_18-functionalized magnetic silica nanoparticles, and the purified samples were de- tected by HPLC-MS/MS. [Result] The detection method showed a good linear rela- tionship in the range of 5-80 ugkg (r=0.993 1). The recovery ranges were between 93%- 104% with the relative standard deviations (RSD) below 11.3%. [Conclusion] Combined with automation equipment, the method is simple, fast, time-saving, and easy to real- ize the automation of sulfadimidine in the royal jelly samples before determination. 展开更多
关键词 Solid phase extraction Magnetic silica nanoparticles Sulfadimidine Highperformance liquid chromatography-tandem mass spectrometry
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Evaluating the potential of surface-modified silica nanoparticles using internal olefin sulfonate for enhanced oil recovery 被引量:2
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作者 Afaque Ahmed Ismail Mohd Saaid +2 位作者 Abdelazim Abbas Ahmed Rashidah M.Pilus Mirza Khurram Baig 《Petroleum Science》 SCIE CAS CSCD 2020年第3期722-733,共12页
Recently,nanoparticles have proven to enhance oil recovery on the core-flood scale in challenging high-pressure high-temperature reservoirs.Nanomaterials generally appear to improve oil production through wettability ... Recently,nanoparticles have proven to enhance oil recovery on the core-flood scale in challenging high-pressure high-temperature reservoirs.Nanomaterials generally appear to improve oil production through wettability alteration and reduction in interfacial tension between oil and water phases.Besides,they are environmentally friendly and cost-effective enhanced oil recovery techniques.Studying the rheological properties of nanoparticles is critical for field applications.The instability of nanoparticle dispersion due to aggregation is considered as an unfavorable phenomenon in nanofluid flooding while conducting an EOR process.In this study,wettability behavior and rheological properties of surface-treated silica nanoparticles using internal olefins sulfonates(IOS20–24 and IOS19–23),anionic surfactants were investigated.Surface modification effect on the stability of the colloidal solution in porous media and oil recovery was inspected.The rheology of pure and surfacetreated silica nanoparticles was investigated using a HPHT rheometer.Morphology and particle size distributions of pure and coated silica nanoparticles were studied using a field emission scanning electron microscope.A series of core-flood runs was conducted to evaluate the oil recovery factor.The coated silica nanoparticles were found to alter rheological properties and exhibited a shear-thinning behavior as the stability of the coated silica nanoparticles could be improved considerably.At low shear rates,the viscosity slightly increases,and the opposite happens at higher shear rates.Furthermore,the surfacemodified silica nanoparticles were found to alter the wettability of the aqueous phase into strongly water-wet by changing the contact angle from 80°to 3°measured against glass slides representing sandstone rocks.Oil–water IFT results showed that the surface treatment by surfactant lowered the oil–water IFT by 30%.Also,the viscosity of brine increased from 0.001 to 0.008 Pa s by introducing SiO2 nanoparticles to the aqueous phase for better displacement efficiency during chemicalassisted EOR.The core-flood experiments revealed that the ultimate oil recovery is increased by approximately 13%with a surfactant-coated silica nanofluid flood after the conventional waterflooding that proves the potential of smart nanofluids for enhancing oil recovery.The experimental results imply that the use of surfactant-coated nanoparticles in tertiary oil recovery could facilitate the displacement efficiency,alter the wettability toward more water-wet and avoid viscous fingering for stable flood front and additional oil recovery. 展开更多
关键词 silica nanoparticles Anionic surfactant Rheological properties of nano fluids Wettability alteration Enhanced oil recovery
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Characterization of modified mesoporous silica nanoparticles as vectors for siRNA delivery 被引量:2
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作者 Anna Slita Anna Egorova +2 位作者 Eudald Casals Anton Kiselev Jessica M.Rosenholm 《Asian Journal of Pharmaceutical Sciences》 SCIE 2018年第6期592-599,共8页
Gene therapy using siRNA molecules is nowadays considered as a promising approach. For successful therapy, development of a stable and reliable vector for siRNA is crucial. Non-viral and non-organic vectors like mesop... Gene therapy using siRNA molecules is nowadays considered as a promising approach. For successful therapy, development of a stable and reliable vector for siRNA is crucial. Non-viral and non-organic vectors like mesoporous silica nanoparticles(MSN) are associated with lack of most viral vector drawbacks, such as toxicity, immunogenicity, but also generally a low nucleic acid carrying capacity. To overcome this hurdle, we here modified the pore walls of MSNs with surface-hyperbranching polymerized poly(ethyleneimine)(hbPEI), which provides an abundance of amino-groups for loading of a larger amount of siRNA molecules via electrostatic adsorption. After loading, the particles were covered with a second layer of pre-polymerized PEI to provide better protection of siRNA inside the pores, more effective cellular uptake and endosomal escape. To test the transfection efficiency of PEI covered si RNA/MSNs, MDA-MB 231 breast cancer cells stably expressing GFP were used. We demonstrate that PEI-coated si RNA/MSN complexes provide more effective delivery of si RNAs compared to unmodified MSNs. Thus, it can be concluded that appropriately surface-modified MSNs can be considered as prospective vectors for therapeutic siRNA delivery. 展开更多
关键词 Gene therapy NANOCARRIERS siRNA delivery Mesoporous silica nanoparticles
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Subchronic Oral Toxicity of Silica Nanoparticles and Silica Microparticles in Rats 被引量:1
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作者 LIANG Chun Lai XIANG Qian +7 位作者 CUI Wen Ming FANG Jin SUN Na Na ZHANG Xiao Peng LI Yong Ning YANG Hui YU Zhou JIA Xu Dong 《Biomedical and Environmental Sciences》 SCIE CAS CSCD 2018年第3期197-207,共11页
Objective To investigate the subchronic oral toxicity of silica nanoparticles(NPs) and silica microparticles(MPs) in rats and to compare the difference in toxicity between two particle sizes.Methods Sprague-Dawley... Objective To investigate the subchronic oral toxicity of silica nanoparticles(NPs) and silica microparticles(MPs) in rats and to compare the difference in toxicity between two particle sizes.Methods Sprague-Dawley rats were randomly divided into seven groups: the control group; the silica NPs low-, middle-, and high-dose groups; and the silica MPs low-, middle-, and high-dose groups [166.7,500, and 1,500 mg/(kg·bw·day)]. All rats were gavaged daily for 90 days, and deionized water was administered to the control group. Clinical observations were made daily, and body weights and food consumption were determined weekly. Blood samples were collected on day 91 for measurement of hematology and clinical biochemistry. Animals were euthanized for necropsy, and selected organs were weighed and fixed for histological examination. The tissue distribution of silicon in the blood, liver,kidneys, and testis were determined.Results There were no toxicologically significant changes in mortality, clinical signs, body weight,food consumption, necropsy findings, and organ weights. Differences between the silica groups and the control group in some hematological and clinical biochemical values and histopathological findings were not considered treatment related. The tissue distribution of silicon was comparable across all groups.Conclusion Our study demonstrated that neither silica NPs nor silica MPs induced toxicological effects after subchronic oral exposure in rats. 展开更多
关键词 Subchronic toxicity silica nanoparticles silica microparticles RATS
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Light and temperature dual responsive pesticide release system based on mesoporous silica nanoparticles modified by dopamine
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作者 XUWen-shuang YANG Zhou-xiao-shuang +1 位作者 ZHANG Guang-yang LIU Hui 《Journal of Central South University》 SCIE EI CAS CSCD 2022年第2期397-409,共13页
A light and temperature dual responsive copolymer,poly(7-(4-vinylbenzy-loxyl)-4-methylcoumarin-co-N vinyl caprolactam-co-tri(ethylene glycol)methyl ether methacrylate)(PVNM),was grafted on the surface of dopamine base... A light and temperature dual responsive copolymer,poly(7-(4-vinylbenzy-loxyl)-4-methylcoumarin-co-N vinyl caprolactam-co-tri(ethylene glycol)methyl ether methacrylate)(PVNM),was grafted on the surface of dopamine based mesoporous silica nanoparticles(MSNs).The resulting polymer brush,MSNs-g-PVNM,was characterized by FT-IR,TEM,TGA and XPS.The dual responsive behaviors of MSNs-g-PVNM were systematically studied.With imidacloprid as the model guest pesticide,the loading percentage and loading efficiency of the polymer brush were determined as 9.2%and 40.6%,respectively.The release efficiency of imidacloprid in MSNs-g-PVNM was the lowest value of 5.4%at 20℃ and 365 nm,and it reached the highest value of 52.4%at 50℃ and 254 nm.The loss percentage of imidacloprid on the leaves contained imidacloprid-loaded MSNs-g-PVNM(8.4%)was much less than that contained only imidacloprid(25.2%)after three rinses.It was confirmed that the release process of imidacloprid was well regulated through changing external conditions such as light and temperature. 展开更多
关键词 N-VINYLCAPROLACTAM controlled release system STIMULI-RESPONSIVE mesoporous silica nanoparticles IMIDACLOPRID
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Delivery of nitric oxide-releasing silica nanoparticles for in vivo revascularization and functional recovery after acute peripheral nerve crush injury
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作者 Jung Il Lee Ji Hun Park +8 位作者 Yeong-Rim Kim Kihak Gwon Hae Won Hwang Gayoung Jung Joo-Yup Lee Jeong-Yun Sun Jong Woong Park Jae Ho Shin Myoung-Ryul Ok 《Neural Regeneration Research》 SCIE CAS CSCD 2022年第9期2043-2049,共7页
Nitric oxide(NO)has been shown to promote revascularization and nerve regeneration after peripheral nerve injury.However,in vivo application of NO remains challenging due to the lack of stable carrier materials capabl... Nitric oxide(NO)has been shown to promote revascularization and nerve regeneration after peripheral nerve injury.However,in vivo application of NO remains challenging due to the lack of stable carrier materials capable of storing large amounts of NO molecules and releasing them on a clinically meaningful time scale.Recently,a silica nanoparticle system capable of reversible NO storage and release at a controlled and sustained rate was introduced.In this study,NO-releasing silica nanoparticles(NO-SNs)were delivered to the peripheral nerves in rats after acute crush injury,mixed with natural hydrogel,to ensure the effective application of NO to the lesion.Microangiography using a polymer dye and immunohistochemical staining for the detection of CD34(a marker for revascularization)results showed that NO-releasing silica nanoparticles increased revascularization at the crush site of the sciatic nerve.The sciatic functional index revealed that there was a significant improvement in sciatic nerve function in NO-treated animals.Histological and anatomical analyses showed that the number of myelinated axons in the crushed sciatic nerve and wet muscle weight excised from NO-treated rats were increased.Moreover,muscle function recovery was improved in rats treated with NO-SNs.Taken together,our results suggest that NO delivered to the injured sciatic nerve triggers enhanced revascularization at the lesion in the early phase after crushing injury,thereby promoting axonal regeneration and improving functional recovery. 展开更多
关键词 crush injury nerve injury nerve regeneration nitric oxide peripheral nerve REVASCULARIZATION silica nanoparticles
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Immobilization of laccase from Myceliophthora thermophila on functionalized silica nanoparticles: Optimization and application in lindane degradation
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作者 Jelena Bebic Katarina Banjanac +4 位作者 Marija Corović Ana Milivojevic Milica Simovic Aleksandar Marinkovic Dejan Bezbradica 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2020年第4期1136-1144,共9页
This work is focused on immobilization of laccase from Myceliophthora thermophila expressed in Aspergillus oryzae(Novozym 51003?laccase)on amino modified fumed nano-silica(AFNS)and the possible use in bioremediation.H... This work is focused on immobilization of laccase from Myceliophthora thermophila expressed in Aspergillus oryzae(Novozym 51003?laccase)on amino modified fumed nano-silica(AFNS)and the possible use in bioremediation.Hereby,for the first time,factors affecting the immobilization of Novozym 51003?laccase on AFNS were investigated for defining the immobilization mechanism and optimizing the utilization of AFNS as support for laccase immobilization.The highest specific activity(13.1 IU·mg-1 proteins)was achieved at offered 160 mg per g of AFNS and for the same offered protein concentration the highest activity immobilization yield,reaching68.3%after the equilibrium time,at optimum pH 5.0,was obtained.Laccase immobilization occurs by adsorption as monolayer enzyme binding in 40 min,following pseudo-first-order kinetics.The possible use of obtained immobilized preparation was investigated in degradation of pesticide lindane.Within 24 h,lindane concentration was reduced to 56.8%of initial concentration and after seven repeated reuses it retained 70%of the original activity. 展开更多
关键词 silica nanoparticles LACCASE Enzyme immobilization LINDANE BIOREMEDIATION
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Dual responsive block copolymer coated hollow mesoporous silica nanoparticles for glucose-mediated transcutaneous drug delivery
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作者 Yaping Wang Songyue Cheng +4 位作者 Wendi Fan Yikun Jiang Jie Yang Zaizai Tong Guohua Jiang 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2022年第11期35-42,共8页
A self-regulated anti-diabetic drug release device mimicking pancreatic cells is highly desirable for the therapy of diabetes. Herein, a glucose-mediated dual-responsive drug delivery system, which combines pH-and H_(... A self-regulated anti-diabetic drug release device mimicking pancreatic cells is highly desirable for the therapy of diabetes. Herein, a glucose-mediated dual-responsive drug delivery system, which combines pH-and H_(2)O_(2)-responsive block copolymer grafted hollow mesoporous silica nanoparticles(HMSNs)with microneedle(MN) array patch, has been developed to achieve self-regulated administration.The poly[4-(4,4,5,5-tetramethyl-1,3,2-dioxaborolan-2-yl)benzyl acrylate]-b-poly[2-(dimethylamino)ethyl methacrylate](PPBEM-b-PDM) polymer serves as gate keeper to prevent drug release from the cavity of HMSNs at normoglycemic level. In contrast, the drug release rate is significantly enhanced upon H_(2)O_(2)and pH stimuli due to the chemical change of H_(2)O_(2)sensitive PPBEM block and acid responsive PDM block. Therefore, incorporation of anti-diabetic drug and glucose oxidase(GOx, which can oxidize glucose to gluconic acid and in-situ produce H_(2)O_(2)) into stimulus polymer coated HMSNs results in a glucose-mediated MN device after depositing the drug-loaded nanoparticles into MN array patch. Both in vitro and in vivo results show this MN device presents a glucose mediated self-regulated drug release characteristic, which possesses a rapid drug release at hyperglycemic level but retarded drug release at normoglycemic level. The result indicates that the fabricated smart drug delivery system is a good candidate for the therapy of diabetes. 展开更多
关键词 Diabetes Transcutaneous microneedles Stimuli-responsive drug release Hollow mesoporous silica nanoparticles Block copolymer
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The role of surface functionalization of silica nanoparticles for bioimaging
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作者 Maria C.Gomes Angela Cunha +1 位作者 Tito Trindade João P.C.Tome 《Journal of Innovative Optical Health Sciences》 SCIE EI CAS 2016年第4期11-26,共16页
Among the several types of inorganic nanoparticles available,silica nanoparticles(SNP)have earned their relevance in biological applications namely,as bioimaging agents.In fact,uorescent SNP(FSNP)have been explored in... Among the several types of inorganic nanoparticles available,silica nanoparticles(SNP)have earned their relevance in biological applications namely,as bioimaging agents.In fact,uorescent SNP(FSNP)have been explored in this-eld as protective nanocarriers,overcoming some limitations presented by conventional organic dyes such as high photobleaching rates.A crucial aspect on the use of uorescent SNP relates to their surface properties,since it determines the extent of interaction between nanoparticles and biological systems,namely in terms of colloidal stability in water,cellular recognition and internalization,tracking,biodistribution and speci-city,among others.Therefore,it is imperative to understand the mechanisms underlying the interaction between biosystems and the SNP surfaces,making surface functionalization a relevant step in order to take full advantage of particle properties.The versatility of the surface chemistry on silica platforms,together with the intrinsic hydrophilicity and biocompatibility,make these systems suitable for bioimaging applications,such as those mentioned in this review. 展开更多
关键词 Fluorescent silica nanoparticles BIOIMAGING surface functionalization nanoparticlecell interactions.
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Incorporation of Sphingosine 1-Phosphate Loaded Mesoporous Silica Nanoparticles into Poly ( L-lactic acid ) Nanofibrous Scaffolds for Bone Tissue Engineering
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作者 秦明 周小军 +2 位作者 张骞骞 苗莹珂 何创龙 《Journal of Donghua University(English Edition)》 EI CAS 2017年第1期164-166,共3页
Controlled release of the functional factors is the key to improve clinical therapeutic efficacy during the tissue repair and regeneration. The thrce-dimensional (3D) scaffold can provide not only physical propertie... Controlled release of the functional factors is the key to improve clinical therapeutic efficacy during the tissue repair and regeneration. The thrce-dimensional (3D) scaffold can provide not only physical properties such as high strength and porosity hut also an optimal environment to enhance tissue regeneration. Sphingosine 1-phosphate (SIP), an angiogenlc factor, was loaded into mesoporous silica nanoparticles (MSNs) and then incorporated into poly ( L-lactic add ) ( PLLA ) nanofibrons scaffold, which was fabricated by thermally induced phase separation (TIPS) method. The prepared scaffolds were examined by attenuated total reflection Fourier transform infrared spectroscopy (ATR-FTIR), scanning electron microscopy ( SEM), and transmission electron microscopy (TEM) and compressive mechanical test. The ATR-FTIR result demonstrated the existence of MSNs in the PLLA nanofibrous scaffold. The SEM images showed that PLLA scaffold had regular pore channel, interconnected pores and nanofibrous structure. The addition of MSNs at appropriate content had no visible effect on the structure of scaffold. The compressive modulus of scaffold containing MSNs was higher than that of the scaffold without MSNs. Furthermore, fluorescein isothiocyanate (FTTC) was used as model molecule to investigate the release behavior of SIP from MSNs- incorporated PLLA (MSNs/PLLA) nanofibrons scaffold. The result showed that the composite scaffold largely reduced the initial burst release and exhibited prolonged release of FITC than MSNs. Thus, these results indicated that SIP-loaded composite uanofibrons scaffold has potential applications for bone tissue engneering. 展开更多
关键词 SCAFFOLD mesoporous silica nanoparticles sphingosine 1- phosphate (ALP) RELEASE
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Mesoporous Silica Nanoparticles for the Analytical Extraction of Triphenyltin from Water
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作者 Awad Aqeel Al-rashdi 《Journal of Chemistry and Chemical Engineering》 2014年第5期461-469,共9页
A rapid, precise, sensitive and simple method has been developed for the extraction and determination of TPT (triphenyltin), DPT (diphenyltin) and MPT (monophenyltin) in seawater samples. The procedure is based ... A rapid, precise, sensitive and simple method has been developed for the extraction and determination of TPT (triphenyltin), DPT (diphenyltin) and MPT (monophenyltin) in seawater samples. The procedure is based on the use of the dual functionalization of mesoporous silica with diol and Cl6 alkane groups for the collection of TPT and its derivatives, DPT and MPT, from seawater samples, followed by ethylation of the target matrices using sodium tetraethylborate (NaBEt4) and quantification by gas chromatography with pulsed flame photometric detection. The modified extraction method replaces conventional solid- and liquid-phase extraction with solid dispersion of silica nanoparticles. The partitioning of the analyte between a carefully size-selected silica nanoparticles (solid phase) and a liquid phase occurs as the solid moves through the sample as a colloidal sol. By tailoring the size of the particles to approximately 250 nm in diameter, they can be easily dispersed in aqueous solution, without the need for any mechanical or hand shaking and the solid can then be readily recovered, together with the analytes, by simple filtration or centrifugation. Recoveries of TPT, DPT and MPT chloride spiked matrices rang from 87.3±1.1 to 98.1±1.3 in seawater samples (n = I 1 samples). The limit of detection obtained was typically in the range of 0.1-3 ng Sn/L. The proposed method shows excellent linearity in the range of 0.5-2 ng Sn/L and good repeatability (RSD 〈 5% at 0.02 ng TPT (as Sn)/L). The method performance is demonstrated with real seawater samples. 展开更多
关键词 TRIPHENYLTIN silica nanoparticles sodium tetraethylborate colloidal sol seawater sample.
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Synthesis and Characterization of Carboxyl-terminated Polyethylene Glycol Functionalized Mesoporous Silica Nanoparticles 被引量:3
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作者 WANG Yu LIU Mingxing 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS 2018年第6期1540-1545,共6页
Colloidal mesoporous silica nanoparticles functionalized with carboxy-terminated polyethylene glycol(CMS-PEG-COOH) were successfully synthesized by covalently grafting dicarboxy-terminated polyethylene glycol(HOOC-PEG... Colloidal mesoporous silica nanoparticles functionalized with carboxy-terminated polyethylene glycol(CMS-PEG-COOH) were successfully synthesized by covalently grafting dicarboxy-terminated polyethylene glycol(HOOC-PEG-COOH) on the surface of the amino functionalized CMS nanoparticles with amide bond as a cross linker. Moreover, the structural and particle properties of CMS-PEG-COOH were characterized by nuclear magnetic resonance spectroscopy(1 H-NMR), transmission electron microscopy(TEM), dynamic light scattering(DLS), nitrogen adsorption-desorption measurements, X-ray diffraction(XRD), and Fourier transform infrared spectroscopy(FT-IR). The nanomaterials presented a relatively uniform spherical shape morphology with diameters of about 120 nm,and favorable dispersibility in weak acid solution. The CMSPEG-COOH exhibited no changes in the state of amorphous, while the mesopores sizes of 5.25 nm might provide the nanomaterials with large capacity for the loading and releasing of drugs. So the results indicated that CMSPEG-COOH might be a critical nanomaterial for drug delivery system in the future. 展开更多
关键词 mesoporous silica nanoparticles polyethylene glycol FUNCTIONALIZATION carboxy-terminated synthesis
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Wettability alteration and retention of mixed polymer-grafted silica nanoparticles onto oil-wet porous medium 被引量:2
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作者 Hamid Daneshmand Masoud Rezaeinasab +1 位作者 Masoud Asgary Meysam Karimi 《Petroleum Science》 SCIE CAS CSCD 2021年第3期962-982,共21页
Enhanced oil recovery(EOR)processes are applied to recover trapped or residual oil in the reservoir rocks after primary and secondary recovery methods.Changing the wettability of the rock from oil-wet to water-wet is ... Enhanced oil recovery(EOR)processes are applied to recover trapped or residual oil in the reservoir rocks after primary and secondary recovery methods.Changing the wettability of the rock from oil-wet to water-wet is named wettability alteration.It is an important factor for EOR.Due to their unique properties,nanoparticles have gained great attention for improving oil recovery.Despite the promising results,the main challenges of applying nanoparticles are related to the colloidal stability of the nanofuids in the harsh conditions of the reservoirs.In recent years,polymer-grafted nanoparticles have been considered as novel promising materials for EOR.The obtained results showed that adding a hydrophobic agent trimethoxy(propyl)silane on the surface of modifed silica nanoparticles with polyethylene glycol methyl ether has an efective role in improving retention and wettability alteration,especially in the oil-wet substrate due to hydrophobic interaction.The modifed silica nanoparticle by mixed polyethylene glycol methyl ether(Mn~5000)and trimethoxy(propyl)silane showed a proper performance at a concentration of 1000 ppm and a salinity range of 2000-40,000 ppm.The obtained fndings can help for a better understanding of the silica nanofuid modifcation with both hydrophilic and hydrophobic agents for the EOR application of near-wellbore. 展开更多
关键词 Wettability alteration RETENTION silica nanoparticle Surface modifcation Enhanced oil recovery
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Co-adsorption behavior of aggregated asphaltenes and silica nanoparticles at oil/water interface and its effect on emulsion stability 被引量:1
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作者 Guang-Yu Sun Hao Zhang +6 位作者 Dai-Wei Liu Chuan-Xian Li Fei Yang Bo Yao Ze Duan Xin-Ya Chen Fu-Jun Sheng 《Petroleum Science》 SCIE CAS CSCD 2022年第4期1793-1802,共10页
In petroleum industry, crude oil emulsions are commonly formed in oilfields. The asphaltenes and fine particles in crude oil may affect the stability of the emulsions by adsorbing at the water/oil interface. In this r... In petroleum industry, crude oil emulsions are commonly formed in oilfields. The asphaltenes and fine particles in crude oil may affect the stability of the emulsions by adsorbing at the water/oil interface. In this research, the effect of silica nanoparticles and asphaltenes on emulsion stability is explored first. The asphaltenes are proved to benefit emulsion stability. Unlike the asphaltenes, however, the modified silica nanoparticles may have positive or negative effect on emulsion stability, depending on the asphaltene concentration and aggregation degree in the emulsions. Further, it is confirmed by conducting interfacial experiment that the asphaltenes and particles can adsorb at the interface simultaneously and determine the properties of the interfacial layer. More in-depth experiments concerning contact angle and asphaltene adsorption amount on the particles indicate that the asphaltenes can modify the wettability of the particles. Higher concentration and lower aggregation degree of the asphaltenes can increase their adsorption amount on the surface of particles and then improve the modification effectiveness of the particles. Resultantly, the particles with good modification effectiveness can enhance the emulsion stability while the particles with poor modification effectiveness will weaken the emulsion stability. 展开更多
关键词 ASPHALTENE silica nanoparticle Co-adsorption behavior Modification effectiveness Emulsion stability
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Investigation into the effect of silica nanoparticles on the rheological characteristics of water-in-heavy oil emulsions 被引量:1
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作者 O.S.Alade D.A.Al Shehri M.Mahmoud 《Petroleum Science》 SCIE CAS CSCD 2019年第6期1374-1386,共13页
The effect of silica nanoparticles on the rheological characteristics of water-in-heavy oil emulsions has been investigated.Enhanced oil recovery methods for heavy oil production(most especially,thermal fluid injectio... The effect of silica nanoparticles on the rheological characteristics of water-in-heavy oil emulsions has been investigated.Enhanced oil recovery methods for heavy oil production(most especially,thermal fluid injection)usually result in the formation of water-in-oil(W/O)emulsion.In reality,the emulsion produced also contains some fine solid mineral particles such as silica,which,depending on its quantity,may alter the viscosity and/or rheological properties of the fluid.A series of binary-component emulsions were separately prepared by dispersing silica nanoparticles[phase fraction,βs,=0.5%–5.75%(wt/v)]in heavy oil(S/O suspension)and by dispersing water[water cut,θw=10%–53%(v/v)]in heavy oil(W/O emulsion).Ternary-component emulsions comprising heavy oil,water droplets and suspended silica nanoparticles(S/W/O)were also prepared with similar ranges ofθw andβs.The viscosity was measured at different shear rates(5.1–1021.4 s-1)and temperatures(30–70°C).Both binary-component and ternary-component emulsion systems were observed to exhibit nonNewtonian shear thinning behaviour.The viscosity of the heavy oil and W/O emulsions increased in the presence of silica nanoparticles.The effect was,however,less signifi cant belowβs=2%(wt/v).Moreover,a generalized correlation has been proposed to predict the viscosity of both binary-component and ternary-component emulsions. 展开更多
关键词 Heavy oil emulsions Heavy oil–silica nanoparticle suspension Viscosity functions Rheological model Complex fluid
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Amphipathicity mediated endocytosis of mesoporous silica nanoparticles with tunable frameworks
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作者 Runfeng Lin Tiancong Zhao +6 位作者 Liang Chen Minchao Liu Hongyue Yu Ruicong Wang Minjia Yuan Xiaomin Li Dongyuan Zhao 《Nano Research》 SCIE EI CSCD 2024年第9期8350-8359,共10页
Due to the amphiphilic nature of phospholipids in the cell membrane,the amphipathicity of the nanomedicine plays a crucial role in the endocytosis.However,limited biological characterization methods restrict the study... Due to the amphiphilic nature of phospholipids in the cell membrane,the amphipathicity of the nanomedicine plays a crucial role in the endocytosis.However,limited biological characterization methods restrict the study of the state of nanoparticles with different amphiphilicities on cell membranes.The understanding of interaction of amphiphilic particle with cell membrane is still lacking.Herein,by combining the dissipative particle dynamics(DPD)with the framework construction of mesoporous silica nanoparticles(MSNs),we demonstrate the enhanced endocytosis induced by the hydrophobicity.DPD results confirm that the presence of hydrophobic groups on the surface of nanoparticles can disturb the integrity of 1-palmitoyl-2-oleoyl-sn-glycero-3-phosphocholine(POPC)membrane and induce activation of phospholipids to a higher energy level,thereby facilitating the wrapping of nanoparticles.To validate the simulation findings,uniform MSNs with hydrophilic pure silica framework and two types of amphiphilic MSNs with varying hydrophilic organic groups in the framework are rationally synthesized by using different silane precursors.The obtained three kinds of MSNs show similar diameter(~100 nm)and mesopores(~2 nm),but distinct hydrophobicity/hydrophilicity ratio.The phenyl-bridged MSN with a carbon content of 27.1%exhibits enhanced cellular uptake,consistent with the theoretical simulation results.This work sheds light on how the surface amphipathicity influences endocytosis through the interaction with cell membrane. 展开更多
关键词 mesoporous silica nanoparticles mesoporous organosilica ENDOCYTOSIS cell membrane AMPHIPATHICITY
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Enhanced multifunctional liquid metal-based hydrogels with vinyl silica nanoparticles for advanced strain sensing applications
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作者 Bingyan Wang Wenxia Liu +5 位作者 Zhaoping Song Guodong Li Dehai Yu Xiaona Liu Huili Wang Shaohua Ge 《Science China Materials》 SCIE EI CAS CSCD 2024年第10期3309-3320,共12页
Conductive hydrogels have garnered considerable interest for their applications in wearable electronic skins,owing to their superior properties.Nevertheless,challenges persist,including low sensitivity,poor cyclic sta... Conductive hydrogels have garnered considerable interest for their applications in wearable electronic skins,owing to their superior properties.Nevertheless,challenges persist,including low sensitivity,poor cyclic stability,and limited tolerance to extreme conditions.This study develops a novel liquid metal-based conductive hydrogel with a dual cross-linked polyacrylic acid(PAA)matrix,employing both“soft”coordination and“hard”covalent cross-linking mechanisms.This hybrid network is formulated using guar gum(GG)-stabilized gallium(Ga)droplets,which catalyze the copolymerization of vinyl-hybrid silica nanoparticles(VSNPs)and acrylic acid(AA).The resultant Ga3+ions interact with carboxyl groups in the PAA,forming soft coordination links that enhance the hydrogel’s rapid gelation.The incorporation of VSNPs significantly enhances the hydrogel’s elasticity,toughness,and low-temperature resilience without glycerol.Notably,its intrinsic moldability,adhesion,and self-healing properties are retained.Applied as a strain sensor,this hydrogel demonstrates a high gauge factor(GF)of 17.4,responsive time of 250 ms for both activation and recovery,an ultra-low detection limit of 0.1%,and excellent durability over 800 cycles at 100%strain.Short-term immersion in a glycerol solution(20 min)further augments its stretchability to 2688%and GF to 28.1 across a strain range of 1325%–1450%,broadening its operational ranges to 0–1450%at−18°C.Prolonged exposure(4 h)also improves water retention and high-temperature resistance,making this hydrogel a promising material for sustainable,high-performance wearable electronics. 展开更多
关键词 vinyl silica nanoparticles liquid metals guar gum HYDROGEL strain sensor
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