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Design of nanocarriers for efficient cellular uptake and endosomal release of small molecule and nucleic

Vaibhav Mundra, Ram I. Mahato

《化学科学与工程前沿（英文）》 2014年 第8卷 第4期   页码 387-404 doi: 10.1007/s11705-014-1457-3

摘要： There are many challenges in developing efficient and target specific delivery systems of small molecule and nucleic acid drugs. Cell membrane presents one of the major barriers for the penetration of hydrophilic macromolecules across the plasma membrane. Nanocarriers have been designed to enhance their cellular uptake via endocytosis but following their cellular uptake, endosomal escape is the rate limiting step which restricts the value associated with the enhanced uptake by nanocarriers. Viruses are an excellent model for efficient cytosolic delivery by nanocarriers. Viruses exploit intracellular cues to release the genome to cytosol. In this review, we first discuss different endocytic uptake pathways and endosomal escape mechanisms. We then summarize the existing tools for studying the intracellular trafficking of nanocarriers. Finally, we highlight the important design elements of recent virus-based nanocarriers for efficient cellular uptake and endosomal escape.

关键词： nanocarrier     cellular uptake     endosomal release     nucleic acid drug    

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Semi-solid materials for controlled release drug formulation: current status and future prospects

Michelle TRAN,Chun WANG

《化学科学与工程前沿（英文）》 2014年 第8卷 第2期   页码 225-232 doi: 10.1007/s11705-014-1429-7

摘要： Semi-solid materials represent an important category of inactive ingredients (excipients) of pharmaceutical products. Here we review several common semi-solid polymers currently used in the controlled release formulations of many drugs. These polymers are selected based on their importance and broad scope of application in FDA-approved drug products and include several polysaccharides (cellulose, starch, chitosan, alginate) and carbomers, a group of mucoadhesive synthetic polymers. Glyceride-based polymers used in self-emulsifying drug delivery systems (SEDDS) will also be discussed for its importance in formulating poorly water-soluble drugs. Unique features and advantages of each type of semi-solid materials are discussed and examples of their use in oral delivery of drugs are provided. Finally, future prospects of developing new and better semi-solid excipients are discussed with the objective of facilitating clinical translation.

关键词： controlled release     drug delivery     semi-solids     polymer     excipient    

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Study on the NOx release rule along the boiler during pulverized coal combustion

JIN Jing, ZHANG Zhongxiao, LI Ruiyang

《能源前沿（英文）》 2007年 第1卷 第1期   页码 91-95 doi: 10.1007/s11708-007-0009-7

摘要： Numerical simulation and experimental study on NO release along the boiler during pulverized coal combustion have been conducted. With the increase of temperature the NO emission increased and the peak value of NO release moved forward. But when the temperature increased to a certain degree, NO emission began to reduce. NO emission increased with the increase of nitrogen content of coal. The peak value of NO release moved backwards with the increase of coal rank. NO emission increased obviously with the increase of stoichiometric ratio. There existed a critical average diameter of the pulverized coal (). If "d, NO emission reduced with the decrease of pulverized coal size. If >, NO emission reduced with the increase of the pulverized coal size. The results showed that the simulation results are in agreement with the experimental results for concentration distribution of NO along the axis of the furnace.
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Capacity estimation and preliminary strategy for reducing the release of dioxins in China

YU Gang, ZHANG Qing, HUANG Jun, CAI Zhenxiao, SUI Qian

《环境科学与工程前沿（英文）》 2007年 第1卷 第1期   页码 13-17 doi: 10.1007/s11783-007-0002-8

摘要： As a party of the Stockholm Convention on Persistent Organic Pollutants, China must submit its national implementation plan (NIP) for this convention. The strategy and action plan for reducing the release of dioxins in China are the most important components of the NIP. Three problems are key points for developing such strategy and action plan what are the key sources for applying the best available technology/best environmental practice (BAT/BEP) to reduce the release of dioxins? How about the capacity for reducing the dioxins release from the key sources? Where are the areas of priority for applying BAT/BEP? This paper shows the efforts towards the solution of these problems. The list of key sources covering about half of the total dioxins release was determined considering four criteria. The capacity of key sources were estimated based on the difference between the emission factor corresponding to the actual situation in 2004 and that corresponding to the scenario that all key sources have been applied BAT/BEP to reduce the dioxins release. The priority analysis using the geographical information system (GIS) tool has revealed that eastern provinces should be of high priority in the future reduction activities of dioxins release in China.

关键词： GIS     difference     capacity     scenario     implementation    

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randomized, controlled, open label non-inferiority trial of intravenous ferric carboxymaltose versus ironsucrose in patients with iron deficiency anemia in China

《医学前沿（英文）》 doi: 10.1007/s11684-023-1001-2

摘要： Iron deficiency (ID) and ID anemia (IDA) pose significant public health concerns in China. Although iron sucrose (IS) treatment is well-established in the country, ferric carboxymaltose (FCM) offers the advantage of higher doses and fewer infusions. This open label, randomized, controlled, non-inferiority trial was conducted at multiple sites in China to compare the outcomes of FCM (maximum of 2 doses, 500 or 1000 mg iron) and IS (up to 11 infusions, 200 mg iron) treatments in subjects with IDA. The primary endpoint was the achievement of hemoglobin (Hb) response (an increase of ≥2 g/dL from baseline) within 8 weeks, whereas secondary endpoints included changes in Hb, transferrin saturation, and serum ferritin levels. Among the 371 randomized subjects, a similar percentage of subjects treated with FCM and IS achieved Hb-response (FCM 99.4%, IS 98.3%), thereby confirming the non-inferiority of FCM compared with IS (difference 1.12 (−2.15, 4.71; 95% confidence interval (CI))). Furthermore, a significantly higher proportion of FCM-treated subjects achieved early Hb-response at Week 2 (FCM 85.2%, IS 73.2%; difference 12.1 (3.31, 20.65; 95% CI)). Additionally, the increase in TSAT and serum ferritin levels from baseline was significantly greater at all time points for FCM-treated subjects. The safety profiles of FCM and IS were comparable, with the exception of transient hypophosphatemia and pyrexia, which are consistent with FCM’s known safety profile. In conclusion, FCM proves to be an efficacious treatment for IDA, providing faster Hb-response and correction of ID with fewer administrations than IS.

关键词： iron deficiency     anemia     intravenous iron     ferric carboxymaltose     iron sucrose     Hb response     early response    

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Synthesis and characterization of biocompatible polyurethanes for controlled release of hydrophobic and

Juichen YANG,Hong CHEN,Yuan YUAN,Debanjan SARKAR,Jie ZHENG

《化学科学与工程前沿（英文）》 2014年 第8卷 第4期   页码 498-510 doi: 10.1007/s11705-014-1451-9

摘要： Design of biocompatible and biodegradable polymer systems for sustained and controlled release of bioactive agents is critical for numerous biomedical applications. Here, we designed, synthesized, and characterized four polyurethane carrier systems for controlled release of model drugs. These polyurethanes are biocompatible and biodegradable because they consist of biocompatible poly(ethylene glycol) or poly(caprolactone diol) as soft segment, linear aliphatic hexamethylene diisocyanate or symmetrical aliphatic cyclic dicyclohexylmethane-4,4′-diisocyanate as hard segment, and biodegradable urethane linkage. They were characterized with Fourier transform infrared spectroscopy, atomic force microscope, and differential scanning calorimetry, whereas their degradation behaviors were investigated in both phosphate buffered saline and enzymatic solutions. By tuning polyurethane segments, different release profiles of hydrophobic and hydrophilic drugs were obtained in the absence and presence of enzymes. Such difference in release profiles was attributed to a complex interplay among structure, hydrophobicity, and degradability of polyurethanes, the size and hydrophobicity of drugs, and drug-polymer interactions. Different drug-polyurethane combinations modulated the distribution and location of the drugs in polymer matrix, thus inducing different drug release mechanisms. Our results highlight an important role of segmental structure of the polyurethane as an engineering tool to control drug release.

关键词： phase structure     degradation     polyurethanes     controlled release     drug delivery    

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Synergistic effects of sodium hypochlorite disinfection and iron-oxidizing bacteria on early corrosionin cast iron pipes

《环境科学与工程前沿（英文）》 2022年 第16卷 第6期 doi: 10.1007/s11783-021-1506-3

摘要：

• The early corrosion process in the cast iron pipes was investigated.

关键词： Cast iron pipe corrosion     Drinking water distribution systems     Chlorine disinfection     Iron-oxidizing bacteria     Coupling effects    

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functional supramolecular nanoparticles based on pillar[5]arene for controlled generation, storage and release

《化学科学与工程前沿（英文）》 2023年 第17卷 第3期   页码 307-313 doi: 10.1007/s11705-022-2216-5

摘要： The storage and controlled release of singlet oxygen (1O2) have attracted increasing attention due to the wide application and microsecond lifetime of 1O2 in water. Herein we provide an integrated nanoplatform consisting of a diphenylanthracene derivative, a water-soluble pillar[5]arene and a photosensitizer tetrakis(4-hydroxyphenyl)porphyrin (TPP), that may provide the controlled generation, storage and release of singlet oxygen. We design a new diphenylanthracene derivative with two trimethylammonium bromide groups on both ends that can be well recognized by the pillar[5]arene. The formed nanocarriers can be used to load TPP through their supramolecular self-assembly. The resulting nanoparticles show good water-solubility and uniform spherical morphology. After laser irradiation (660 nm), the nanoparticles exhibit excellent ability for the generation and storage of 1O2. When the irradiated nanoparticles are heated above 80 °C, 1O2 can be released from the system. Therefore, in this paper we pioneer the use of noncovalent interaction to integrate the diphenylanthracene derivatives and photosensitizers into one functional system, which provides a new strategy for the controlled generation, storage and release of singlet oxygen. We believe this groundbreaking strategy will have a great potential in providing necessary amounts of 1O2 for the photodynamic therapy of tumors in dark.

关键词： storage and controlled release of singlet oxygen     supramolecular nanoparticles     noncovalent interactions     pillararenes     diphenylanthracene     photosensitizers    

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Phosphorus release potential and pollution characteristics of sediment in downstream Nansi Lake, China

Zhijian LI, Qinyan YUE, Baoyu GAO, Yanwen WANG, Qing LIU

《环境科学与工程前沿（英文）》 2012年 第6卷 第2期   页码 162-170 doi: 10.1007/s11783-011-0313-7

摘要： The research aimed to evaluate present and potential phosphorous pollution due to high sedimentary phosphorus load and release from sediment, when external phosphorus was reduced in downstream Nansi Lake. Pollution load of the sediment and overlying water was investigated. Kinetics and isotherms of adsorption/release of sedimentary phosphorus were studied to determine equilibrium phosphate concentration (EPC ) and release potential. Kinetics of phosphorus adsorption on sediment and release from sediment were well described by both the pseudo-first-order rate equation and the pseudo-second-order rate equation, but more appropriate to the pseudo-second-order rate equation with the adsorption/release capacity more close to the measured values, suggesting that the processes were chemically rate controlled and dependent on adsorption capacity. Soluble reactive phosphorus (SRP) sorption isotherms on sediment were best fitted by the modified Langmuir model indicating a monolayer adsorption. By comparing EPC and SRP of water, the status (adsorption, releasing or in equilibrium) of sediment phosphorus could be determined. The sediments at site S1, S3, S4, S5, and S7 where the EPC s were greater than the SRPs, had a potential to release phosphorus into the water column. However, those sediments at S9, S10, and S12, where the EPC s were approximately equal to the SRPs, were in impermanent equilibrium with overlying water in status of phosphorus, the sediments can be likely to release phosphorus to the water column once the equilibrium was broken. Therefore, sedimentary phosphorus can be a secondary pollution source in downstream Nansi Lake.

关键词： Nansi Lake     sediment     phosphorus     release potential     equilibrium phosphate concentration    

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Controlled drug release of 5-amino salicylic acid by poly(2-hydroxyethylmethacrylate) grafted agar

G. Usha RANI,Kartick Prasad DEY,Srijita BHARTI,Sumit MISHRA

《化学科学与工程前沿（英文）》 2014年 第8卷 第4期   页码 465-470 doi: 10.1007/s11705-014-1452-8

摘要： The utilization of poly (2-hydroxyethylmethacrylate) grafted agar (Ag-g-P(HEMA)) as a matrix for the controlled release of 5-aminosalicylic acid was investigated. Grafted copolymers of 2-hydroxyethylmethacrylate (HEMA) monomers on agar were synthesized by microwave assisted method. drug release studies were performed at pH values of 2 and 7 in order to investigate the possibility of pH triggered release for colon targeted drug delivery. Further, the percent grafting . (the time taken for release of 50% of the enclosed drug) value was studied and the results indicate that it may be possible to develop a programmable drug release matrix based on grafted polysaccharide. Ag-g-P(HEMA) appears to be a useful matrix for controlled release.

关键词： agar     controlled drug release     5-Amino salicylic acid     poly(2-hydroxyethylmethacrylate) grafted agar    

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Performance of iron-air battery with iron nanoparticle-encapsulated C–N composite electrode

《能源前沿（英文）》 doi: 10.1007/s11708-023-0913-5

摘要： Highly efficient and stable iron electrodes are of great significant to the development of iron-air battery (IAB). In this paper, iron nanoparticle-encapsulated C–N composite (NanoFe@CN) was synthesized by pyrolysis using polyaniline as the C–N source. Electrochemical performance of the NanoFe@CN in different electrolytes (alkaline, neutral, and quasi-neutral) was investigated via cyclic voltammetry (CV). The IAB was assembled with NanoFe@CN as the anode and IrO2 + Pt/C as the cathode. The effects of different discharging/charging current densities and electrolytes on the battery performance were also studied. Neutral K2SO4 electrolyte can effectively suppress the passivation of iron electrode, and the battery showed a good cycling stability during 180 charging/discharging cycles. Compared to the pure nano-iron (NanoFe) battery, the NanoFe@CN battery has a more stable cycling stability either in KOH or NH4Cl + KCl electrolyte.

关键词： energy storage and conversion     metallic composites     nanocomposites     iron-air battery     iron anode    

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Redox reactions of iron and manganese oxides in complex systems

Jianzhi Huang, Huichun Zhang

《环境科学与工程前沿（英文）》 2020年 第14卷 第5期 doi: 10.1007/s11783-020-1255-8

摘要： • Mechanisms of redox reactions of Fe- and Mn-oxides were discussed. • Oxidative reactions of Mn- and Fe-oxides in complex systems were reviewed. • Reductive reaction of Fe(II)/iron oxides in complex systems was examined. • Future research on examining the redox reactivity in complex systems was suggested. Conspectus Redox reactions of Fe- and Mn-oxides play important roles in the fate and transformation of many contaminants in natural environments. Due to experimental and analytical challenges associated with complex environments, there has been a limited understanding of the reaction kinetics and mechanisms in actual environmental systems, and most of the studies so far have only focused on simple model systems. To bridge the gap between simple model systems and complex environmental systems, it is necessary to increase the complexity of model systems and examine both the involved interaction mechanisms and how the interactions affected contaminant transformation. In this Account, we primarily focused on (1) the oxidative reactivity of Mn- and Fe-oxides and (2) the reductive reactivity of Fe(II)/iron oxides in complex model systems toward contaminant degradation. The effects of common metal ions such as Mn2+ , Ca2+, Ni2+, Cr3+ and Cu2+, ligands such as small anionic ligands and natural organic matter (NOM), and second metal oxides such as Al, Si and Ti oxides on the redox reactivity of the systems are briefly summarized.

关键词： Iron oxides     manganese oxides     reduction     oxidation     complex systems     reaction kinetics and mechanisms    

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Mechanical properties of vanadium-alloyed austempered ductile iron for crankshaft applications

《机械工程前沿（英文）》 2023年 第18卷 第3期 doi: 10.1007/s11465-023-0746-2

摘要： This study focused on the development of austempered ductile iron (ADI) with desirable combination of mechanical properties for crankshaft applications by the combined effect of vanadium (V) alloying and an optimized heat treatment process. The produced unalloyed GGG60, 0.15% V-alloyed GGG60 (V-15), and 0.30% V-alloyed GGG60 samples were subjected to austenitizing at 900 °C for 1 h and subsequent austempering processes at 250, 300, and 350 °C for 15, 30, 60, 90, and 180 min. As a result of these austempering processes, different bainitic structures were obtained, which led to the formation of diverse combinations of mechanical properties. The mechanical properties of the austempered samples were tested comprehensively, and the results were correlated with their microstructures and the stability of the retained austenite phases. From the microstructural observations, the V-alloyed samples exhibited a finer microstructure and a more acicular ferrite phase than unalloyed samples. The V addition delayed the coarsening of the acicular ferrite structures and considerably contributed to the improvement of the mechanical properties of GGG60. Moreover, the X-ray diffraction results revealed that the retained austenite volume and the carbon enrichment of austenite phases in ADI samples were remarkably affected by the addition of vanadium. The increase in volume fraction of retained austenite and its carbon content provided favorable ductility and toughness to V-15, as confirmed by the elongation and impact test results. Consequently, the dual-phase ausferrite microstructure of V-15 that was austempered at 300 °C for 60 min exhibited high strength with substantial ductility and toughness for crankshaft applications.

关键词： austempered ductile iron (ADI)     vanadium alloying     mechanical properties     crankshafts     retained austenite    

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A red water occurrence in drinking water distribution systems caused by changes in water source in Beijing, China: mechanism analysis and control measures

ZHANG Xiaojian,MI Zilong,WANG Yang,LIU Shuming,NIU Zhangbin,LU Pinpin,WANG Jun,GU Junnong,CHEN Chao

《环境科学与工程前沿（英文）》 2014年 第8卷 第3期   页码 417-426 doi: 10.1007/s11783-013-0558-4

摘要： A red water phenomenon occurred in several communities few days after the change of water source in Beijing, China in 2008. In this study, the origin of this problem, the mechanism of iron release and various control measures were investigated. The results indicated that a significant increase in sulphate concentration as a result of the new water source was the cause of the red water phenomenon. The mechanism of iron release was found that the high-concentration sulphate in the new water source disrupted the stable shell of scale on the inner pipe and led to the release of iron compounds. Experiments showed that the iron release rate in the new source water within pipe section was over 11-fold higher than that occurring within the local source water. The recovery of tap water quality lasted several months despite ameliorative measures being implemented, including adding phosphate, reducing the overall proportion of the new water source, elevating the pH and alkalinity, and utilizing free chlorine as a disinfectant instead of chloramine. Adding phosphate was more effective and more practical than the other measures. The iron release rate was decreased after the addition of 1.5 mg·L orthophosphate- P, tripolyphosphate-P and hexametaphosphate-P by 68%, 83% and 87%, respectively. Elevating the pH and alkalinity also reduced the iron release rate by 50%. However, the iron release rate did not decreased after replacing chloramine by 0.5–0.8 mg·L of free chlorine as disinfectant.

关键词： iron release     drinking water distribution system     sulphate     phosphate     red water control     water quality stability    

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Scrap Iron Filings assisted nitrate and phosphate removal in low C/N waters using mixed microbial culture

《环境科学与工程前沿（英文）》 2021年 第15卷 第4期 doi: 10.1007/s11783-020-1358-2

摘要：

• Microbes enhance denitrification under varying DO concentrations and SIF dosages.

关键词： Scrap iron filing     Nitrate removal     Phosphate removal     Mixed culture denitrification     Zero valent iron    

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标题 作者 时间 类型 操作

Design of nanocarriers for efficient cellular uptake and endosomal release of small molecule and nucleic

Vaibhav Mundra, Ram I. Mahato

期刊论文

Semi-solid materials for controlled release drug formulation: current status and future prospects

Michelle TRAN,Chun WANG

期刊论文

Study on the NOx release rule along the boiler during pulverized coal combustion

JIN Jing, ZHANG Zhongxiao, LI Ruiyang

期刊论文

Capacity estimation and preliminary strategy for reducing the release of dioxins in China

YU Gang, ZHANG Qing, HUANG Jun, CAI Zhenxiao, SUI Qian

期刊论文

randomized, controlled, open label non-inferiority trial of intravenous ferric carboxymaltose versus ironsucrose in patients with iron deficiency anemia in China

期刊论文

Synthesis and characterization of biocompatible polyurethanes for controlled release of hydrophobic and

Juichen YANG,Hong CHEN,Yuan YUAN,Debanjan SARKAR,Jie ZHENG

期刊论文

Synergistic effects of sodium hypochlorite disinfection and iron-oxidizing bacteria on early corrosionin cast iron pipes

期刊论文

functional supramolecular nanoparticles based on pillar[5]arene for controlled generation, storage and release

期刊论文

Phosphorus release potential and pollution characteristics of sediment in downstream Nansi Lake, China

Zhijian LI, Qinyan YUE, Baoyu GAO, Yanwen WANG, Qing LIU

期刊论文

Controlled drug release of 5-amino salicylic acid by poly(2-hydroxyethylmethacrylate) grafted agar

G. Usha RANI,Kartick Prasad DEY,Srijita BHARTI,Sumit MISHRA

期刊论文

Performance of iron-air battery with iron nanoparticle-encapsulated C–N composite electrode

期刊论文

Redox reactions of iron and manganese oxides in complex systems

Jianzhi Huang, Huichun Zhang

期刊论文

Mechanical properties of vanadium-alloyed austempered ductile iron for crankshaft applications

期刊论文

A red water occurrence in drinking water distribution systems caused by changes in water source in Beijing, China: mechanism analysis and control measures

ZHANG Xiaojian,MI Zilong,WANG Yang,LIU Shuming,NIU Zhangbin,LU Pinpin,WANG Jun,GU Junnong,CHEN Chao

期刊论文

Scrap Iron Filings assisted nitrate and phosphate removal in low C/N waters using mixed microbial culture

期刊论文