Posaconazole(PCZ)is a broad-spectrum anti-fungal drug approved by FDA and currently used off-label for the treatment of fungal keratitis(FK).Although ocular route serves as the most bioavailable route for treating FK,...Posaconazole(PCZ)is a broad-spectrum anti-fungal drug approved by FDA and currently used off-label for the treatment of fungal keratitis(FK).Although ocular route serves as the most bioavailable route for treating FK,delivery of PCZ to the eye remains a challenge due to poor permeation though the cornea and rapid elimination from the eye.Here we outline a comprehensive formulation development process,beginning with in silico studies,progressing through in vitro evaluations,and ultimately achieving therapeutic benefits in vivo.We report modified niosome-like surfactant vesicles,hereafter termed as NioTherms,formulated using a novel and simple heat-mix method,encapsulating PCZ for ocular administration in the form of an in situ gel.Excipient screening performed using in silico simulations highly correlate with in vitro studies(R^(2)=0.77),guiding optimization by Quality by Design(QbD)approach for encapsulating PCZ in NioTherms resulting in particles with an average size of 180.7±2.3 nm,zeta potential of +27.5±2.2 mV and entrapment efficiency of 87.6%±1.7%.A 2-fold increase in both mucin binding and cellular uptake indicates a functional role of positive surface charge in enhancingmucoadhesive properties of PCZ-NioTherms.In an in vivo murine ocular keratitis model,we demonstrate a 2-fold enhancement in trans-corneal permeability of PCZ-NioTherms and a 3-fold reduction in fungal burden compared to the control standard of care,the PCZ solution.Owing to a facile formulation process,we anticipate that PCZ-NioTherms would serve as a clinically translatable and patient compliant therapeutic intervention for treating FK.展开更多
Despite the growing interest in fast-cha rging solid-state lithium(Li)-metal batteries(SSLMBs),their practical implementation has yet to be achieved,primarily due to an incomplete understanding of the disparate and of...Despite the growing interest in fast-cha rging solid-state lithium(Li)-metal batteries(SSLMBs),their practical implementation has yet to be achieved,primarily due to an incomplete understanding of the disparate and often conflicting requirements of the bulk electrolyte and the electrode-electrolyte interphase.Here,we present a weakly coordinating cationic polymer electrolyte(WCPE)specifically designed to regulate the Li^(+)coordination structure,thereby enabling fast-charging SSLMBs.The WCPE comprises an imidazolium-based polycationic matrix combined with a succinonitrile(SN)-based highconcentration electrolyte.Unlike conventional neutral polymer matrices,the polycationic matrix in the WCPE competes with Li^(+)for interactions with SN,weakening the original coordination between SN and Li^(+).This modulation of SN-Li^(+)interaction improves both Li^(+)conductivity of the WCPE(σ_(Li^(+))=1.29mS cm^(-1))and redox kinetics at the electrode-electrolyte interphase.Consequently,SSLMB cells(comprising LiFePO_(4)cathodes and Li-metal anodes)with the WCPE achieve fast-charging capability(reaching over 80%state of charge within 10 min),outperforming those of previously reported polymer electrolytebased SSLMBs.展开更多
Developing cost-effective single-crystalline Ni-rich Co-poor cathodes operating at high-voltage is one of the most important ways to achieve higher energy Li-ion batteries. However, the Li/O loss and Li/Ni mixing unde...Developing cost-effective single-crystalline Ni-rich Co-poor cathodes operating at high-voltage is one of the most important ways to achieve higher energy Li-ion batteries. However, the Li/O loss and Li/Ni mixing under high-temperature lithiation result in electrochemical kinetic hysteresis and structural instability. Herein, we report a highly-ordered single-crystalline LiNi0.85Co0.05Mn0.10O2(NCM85) cathode by doping K+and F-ions. To be specific, the K-ion as a fluxing agent can remarkably decrease the solid-state lithiation temperature by ~30°C, leading to less Li/Ni mixing and oxygen vacancy. Meanwhile, the strong transitional metal(TM)-F bonds are helpful for enhancing de-/lithiation kinetics and limiting the lattice oxygen escape even at 4.5 V high-voltage. Their advantages synergistically endow the single-crystalline NCM85 cathode with a very high reversible capacity of 222.3 mAh g-1. A superior capacity retention of 91.3% is obtained after 500 times at 1 C in pouch-type full cells, and a prediction value of 75.3% is given after cycling for 5000 h. These findings are reckoned to expedite the exploitation and application of high-voltage single-crystalline Ni-rich cathodes for next-generation Li-ion batteries.展开更多
The occurrence,development,and metastasis of tumors often entail abnormal expression of genetic substances.Monitoring and regulating changes in intracellular nucleic acid substances hold promise for achieving accurate...The occurrence,development,and metastasis of tumors often entail abnormal expression of genetic substances.Monitoring and regulating changes in intracellular nucleic acid substances hold promise for achieving accurate tumor diagnosis and effective treatment.However,the effectiveness of integrated tumor diagnosis and treatment based on functional nucleic acids still needs to be improved.In this study,we engineered a multifunctional nucleic acid delivery system grounded in a cationic covalent organic framework carrier.This system not only showcases effective gene silencing but also boasts high sensitivity in detecting miR21 levels within tumor cells,enabling real-time monitoring of tumor gene therapy efficacy.The construction of this integrated functional nucleic acid delivery platform provides new ideas for precise tumor detection and effective tumor treatment.展开更多
Living cationic polymerization of 4-acetoxystyrene(STO)was conducted in CH_(2)Cl_(2) at-15℃ using a dicumyl chloride(DCC)/SnCl_(4)/nBu_(4)NBr initiating system.Impurity moisture initiation was inhibited by adding pro...Living cationic polymerization of 4-acetoxystyrene(STO)was conducted in CH_(2)Cl_(2) at-15℃ using a dicumyl chloride(DCC)/SnCl_(4)/nBu_(4)NBr initiating system.Impurity moisture initiation was inhibited by adding proton trap 2,6-di-tert-butylpyridine(DTBP),and the controlled initiation of DCC was confirmed by ^(1)H nuclear magnetic resonance(^(1)H-NMR)spectroscopy and matrix-assisted laser desorption ionization time-offlight mass(MALDI-TOF-MS)spectrometry.The polymerization kinetics were analyzed to for optimizing the polymerization rate.Allyl-telechelic PSTOs(allyl-PSTO-allyl)with molecular weight(Mn)range of 3540–7800 g/mol and narrow molecular weight dispersity(Mw/Mn)about 1.25 were prepared through nucleophilic substitution with allyltrimethylsilane(ATMS)at approximately 40%monomer conversion.The experimental results indicate that the substitution efficiency of ATMS increased with higher ATMS concentration,temperature,and extended reaction time.Nearly unity ally-functionality for allyl-PSTO-allyl was achieved by adding sufficient SnCl_(4) prior to the substitution.展开更多
Aqueous zincion batteries are highly favored for grid-level energy storage owing to their low cost and high safety,but their practical application is limited by slow ion migration.To address this,a strategy has been d...Aqueous zincion batteries are highly favored for grid-level energy storage owing to their low cost and high safety,but their practical application is limited by slow ion migration.To address this,a strategy has been developed to create a cation-accelerating electric field on the surface of the cathode to achieve ultrafast Zn^(2+)diffusion kinetics.By employing electrodeposition to coat MoS_(2)on the surface of BaV_(6)O_(16)·3H_(2)O nanowires,the directional builtin electric field generated at the heterointerface acts as a cation accelerator,continuously accelerating Zn^(2+)diffusion into the active material.The optimized Zn^(2+)diffusion coefficient in CC@BaV-V_(6)O_(16)·3H_(2)@MoS_(2)(7.5×10^(8)cm^(2)s^(-1)) surpasses that of most reported V-based cathodes.Simultaneously,MoS_(2)serving as a cathodic armor extends the cycling life of the Zn-CC@BaV_(6)O_(16)·3H_(2)@MoS_(2)full batteries to over 10000 cycles.This work provides valuable insights into optimizing ion diffusion kinetics for high-performance energy storage devices.展开更多
It is well known that cationic polymers have excellent antimicrobial capacity accompanied with high biotoxicity,to reduce biotoxicity needs to decrease the number of cationic groups on polymers,which will influence an...It is well known that cationic polymers have excellent antimicrobial capacity accompanied with high biotoxicity,to reduce biotoxicity needs to decrease the number of cationic groups on polymers,which will influence antimicrobial activity.It is necessary to design a cationic polymer mimic natural antimicrobial peptide with excellent antibacterial activity and low toxicity to solve the above dilemma.Here,we designed and prepared a series of cationic poly(β-amino ester)s(PBAEs)with different cationic contents,and introducing hydrophobic alkyl chain to adjust the balance between antimicrobial activity and biotoxicity to obtain an ideal antimicrobial polymer.The optimum one of synthesized PBAE(hydrophilic cationic monomer:hydrophobic monomer=5:5)was screened by testing cytotoxicity and minimum inhibitory concentration(MIC),which can effectively kill S.aureus and E.coli with PBAE concentration of15μg/m L by a spread plate bacteriostatic method and dead and alive staining test.The way of PBAE killing bacterial was destroying the membrane like natural antimicrobial peptide observed by scanning electron microscopy(SEM).In addition,PBAE did not exhibit hemolysis and cytotoxicity.In particular,from the result of animal tests,the PBAE was able to promote healing of infected wounds from removing mature S.aureus and E.coli on the surface of infected wound.As a result,our work offers a viable approach for designing antimicrobial materials,highlighting the significant potential of PBAE polymers in the field of biomedical materials.展开更多
Lithium-rich layered oxides (LLOs) are increasingly recognized as promising cathode materials for nextgeneration high-energy-density lithium-ion batteries (LIBs).However,they suffer from voltage decay and low initial ...Lithium-rich layered oxides (LLOs) are increasingly recognized as promising cathode materials for nextgeneration high-energy-density lithium-ion batteries (LIBs).However,they suffer from voltage decay and low initial Coulombic efficiency (ICE) due to severe structural degradation caused by irreversible O release.Herein,we introduce a three-in-one strategy of increasing Ni and Mn content,along with Li/Ni disordering and TM–O covalency regulation to boost cationic and anionic redox activity simultaneously and thus enhance the electrochemical activity of LLOs.The target material,Li_(1.2)Ni_(0.168)Mn_(0.558)Co_(0.074)O_(2)(L1),exhibits an improved ICE of 87.2%and specific capacity of 293.2 mA h g^(-1)and minimal voltage decay of less than 0.53 m V cycle-1over 300 cycles at 1C,compared to Li_(1.2)Ni_(0.13)Mn_(0.54)Co_(0.13)O_(2)(Ls)(274.4 mA h g^(-1)for initial capacity,73.8%for ICE and voltage decay of 0.84 mV/cycle over 300 cycles at 1C).Theoretical calculations reveal that the density of states (DOS) area near the Fermi energy level for L1 is larger than that of Ls,indicating higher anionic and cationic redox reactivity than Ls.Moreover,L1 exhibits increased O-vacancy formation energy due to higher Li/Ni disordering of 4.76%(quantified by X-ray diffraction Rietveld refinement) and enhanced TM–O covalency,making lattice O release more difficult and thus improving electrochemical stability.The increased Li/Ni disordering also leads to more Ni^(2+)presence in the Li layer,which acts as a pillar during Li+de-embedding,improving structural stability.This research not only presents a viable approach to designing low-Co LLOs with enhanced capacity and ICE but also contributes significantly to the fundamental understanding of structural regulation in high-performance LIB cathodes.展开更多
The development of flexible zinc-ion batteries(ZIBs)faces a threeway trade-off among the ionic conductivity,Zn^(2+)mobility,and the electrochemical stability of hydrogel electrolytes.To address this challenge,we desig...The development of flexible zinc-ion batteries(ZIBs)faces a threeway trade-off among the ionic conductivity,Zn^(2+)mobility,and the electrochemical stability of hydrogel electrolytes.To address this challenge,we designed a cationic hydrogel named PAPTMA to holistically improve the reversibility of ZIBs.The long cationic branch chains in the polymeric matrix construct express pathways for rapid Zn^(2+)transport through an ionic repulsion mechanism,achieving simultaneously high Zn^(2+)transference number(0.79)and high ionic conductivity(28.7 mS cm−1).Additionally,the reactivity of water in the PAPTMA hydrogels is significantly inhibited,thus possessing a strong resistance to parasitic reactions.Mechanical characterization further reveals the superior tensile and adhesion strength of PAPTMA.Leveraging these properties,symmetric batteries employing PAPTMA hydrogel deliver exceeding 6000 h of reversible cycling at 1 mA cm^(−2) and maintain stable operation for 1000 h with a discharge of depth of 71%.When applied in 4×4 cm2 pouch cells with MnO_(2) as the cathode material,the device demonstrates remarkable operational stability and mechanical robustness through 150 cycles.This work presents an eclectic strategy for designing advanced hydrogels that combine high ionic conductivity,enhanced Zn^(2+)mobility,and strong resistance to parasitic reactions,paving the way for long-lasting flexible ZIBs.展开更多
The flotation of diaspore and three kinds of silicate minerals, including kaolinite, illite and pyrophyllite, using an organosilicon cationic surfactant (TAS101) as collector and starch as depressant was investigated....The flotation of diaspore and three kinds of silicate minerals, including kaolinite, illite and pyrophyllite, using an organosilicon cationic surfactant (TAS101) as collector and starch as depressant was investigated. The results show that both diaspore and aluminosilicate minerals float readily with organosilicon cationic collector TAS101 at pH values of 4 to 10. Starch has a strong depression effect for diaspore in the alkaline pH region but has little influence on the flotation of aluminosilicate minerals. It is possible to separate diaspore from aluminosilicate minerals using the organosilicon cationic collector and starch depressant. Further studies of bauxite ore flotation were also conducted, and the reverse flotation separation process was adopted. The concentrates with the mass ratio of Al2O3 to SiO2 of 9.58 and Al2O3 recovery of 83.34% are obtained from natural bauxite ore with the mass ratio of Al2O3 to SiO2 of 6.1 at pH value of 11 using the organosilicon cationic collector and starch depressant.展开更多
Gemini quaternary ammonium salt surfactants, butane-a, co-bis（dimethyl dodeculammonium bromide） （BDDA） ethane-a, fl-bis（dimethyl dodeculammonium bromide） （EDDA） were adopted to comparatively study the flotatio...Gemini quaternary ammonium salt surfactants, butane-a, co-bis（dimethyl dodeculammonium bromide） （BDDA） ethane-a, fl-bis（dimethyl dodeculammonium bromide） （EDDA） were adopted to comparatively study the flotation behaviors of kaolinite, pyrophyllite and illite. It was found that three silicate minerals all exhibited good floatability with Gemini cationic surfactants as collectors over a wide pH range, while BDDA showed a stronger collecting power than EDDA. FTIR spectra and zeta potential analysis indicated that the mechanism of adsorption of Gemini collector molecules on three silicate minerals surfaces was almost identical for the electronic attraction and hydrogen bonds effect. The theoretically obtained results of density functional theory （DFT） at B3LYP/6-31G （d） level demonstrated the stronger collecting power of BDDA presented in the floatation test and zeta potential measurement.展开更多
The cationic guar （CG） is synthesized and the rheological behavior of aqueous solutions of CG in the presence of sodium dodecyl sulfate （SDS） is studied in detail. The steady viscosity measurements show that the z...The cationic guar （CG） is synthesized and the rheological behavior of aqueous solutions of CG in the presence of sodium dodecyl sulfate （SDS） is studied in detail. The steady viscosity measurements show that the zero shear viscosity enhancement can be almost 3 orders of magnitude as the concentration of SDS increases from 0 to 0.043%. The gel-like formation is observed as the concentration of SDS is greater than 0.016%. The oscillatory rheological measurements of CG solutions in the presence of SDS show that the crossover modulus is almost independent of the concentration of SDS whereas the apparent relaxation time increases swiftly upon increasing the concentration of SDS. The experimental results indicate that the strength rather than the number of the cross-links is greatly affected by SDS molecules. The mechanism concerning the effect of SDS upon the rheology of CG solutions can be coined by the two-stage model. Before the formation of cross-links at the critical concentration, the electrostatic interaction between SDS and cationic site of CG chains plays a key role and the SDS molecules bind to CG chains through the electrostatic interaction. After the formation of cross-links at the concentration greater than the critical concentration, the cooperative hydrophobic interaction become dominant and SDS molecules bind to the cross-links through the hydrophobic interaction. The theological behavior of aqueous solutions of CG in the presence of SDS is chiefly determined by the micelle-like cross-links between CG chains. In fact, the flow activation energy of CG solution, obtained from the temperature dependence of the apparent relaxation time, falls in the range of transferring a hydrophobic tail of SDS from the micelle to an aqueous environment.展开更多
Dendrite growth represents one of the most significant challenges that impede the development of aqueous zinc-ion batteries.Herein,Gd^(3+)ions are introduced into conventional electrolytes as a microlevelling agent to...Dendrite growth represents one of the most significant challenges that impede the development of aqueous zinc-ion batteries.Herein,Gd^(3+)ions are introduced into conventional electrolytes as a microlevelling agent to achieve dendrite-free zinc electrodeposition.Simulation and experimental results demonstrate that these Gd^(3+)ions are preferentially adsorbed onto the zinc surface,which enables dendritefree zinc anodes by activating the microlevelling effect during electrodeposition.In addition,the Gd^(3+)additives effectively inhibit side reactions and facilitate the desolvation of[Zn(H_(2)O)_(6)]^(2+),leading to highly reversible zinc plating/stripping.Due to these improvements,the zinc anode demonstrates a significantly prolonged cycle life of 2100 h and achieves an exceptional average Coulombic efficiency of 99.72%over 1400 cycles.More importantly,the Zn//NH_(4)V_(4)O_(10)full cell shows a high capacity retention rate of 85.6%after 1000 cycles.This work not only broadens the application of metallic cations in battery electrolytes but also provides fundamental insights into their working mechanisms.展开更多
Cationic fluorinated acrylate latex was prepared via semi-continuous emulsion copolymerization of cationic monomer and other monomers. The resultant latex and its film were characterized with dynamic light scattering ...Cationic fluorinated acrylate latex was prepared via semi-continuous emulsion copolymerization of cationic monomer and other monomers. The resultant latex and its film were characterized with dynamic light scattering detector and contact angle meter. Influences of amount of DMDAAC on the properties of resultant latex and its film were investigated in detail. Results show that the particle size of the latex has the minimum value knd the zeta potential of the latex is increased when the amount of DMDAAC is increased. In addition, the particle size of the latex is unimodal distribution when the amount of DMDAAC is not more than 2.5%. However, the particle size of the latex is bimodal distribution when the amount of DMDAAC is more than 2.5%. The contact angle is varied slightly with the increase of amount of DMDAAC when it is not more than 2.5%. Nevertheless, the contact angle is decreased with the increase of the amount of DMDAAC when it is more than 2.5%.展开更多
In this work, a fluorescent monomer 2-（9-carbazolyl） ethyl vinyl ether（CEVE） was synthesized in our lab, and its photo-induced living cationic copolymerization behavior with isobutyl vinyl ether（IBVE） was invest...In this work, a fluorescent monomer 2-（9-carbazolyl） ethyl vinyl ether（CEVE） was synthesized in our lab, and its photo-induced living cationic copolymerization behavior with isobutyl vinyl ether（IBVE） was investigated in detail using diphenyliodonium chloride（DPICl）/2,2-dimethoxy-2-phenylacetophenone（DMPA） and zinc bromide（Zn Br2） initiating system in dichloromethane solution at 5 °C, -5 °C, and -15 °C, respectively. The living nature of this copolymerization system was confirmed by adding fresh comonomer method after the copolymerization almost finished. In addition, the obtained fluorescent copolymer poly（IBVE-co-CEVE） has a low glass transition temperature（Tg）, below -10 °C.展开更多
Introduction Cationic starches are a series of products of which various sorts with different properties and usages can all be produced via cationic reactions by using different types of etherification agents under di...Introduction Cationic starches are a series of products of which various sorts with different properties and usages can all be produced via cationic reactions by using different types of etherification agents under different conditions. As an additive and strengthening agent,展开更多
In this study, the novel RGD-modified stabilized cationic liposomes were developed as the delivery vehicle for siRNA targeting human MDR1 gene. The complex of cationic liposomes and siRNA, RGD-Lipo-siRNA, was prepared...In this study, the novel RGD-modified stabilized cationic liposomes were developed as the delivery vehicle for siRNA targeting human MDR1 gene. The complex of cationic liposomes and siRNA, RGD-Lipo-siRNA, was prepared with a narrow size distribution below 200 nm. It was shown that the encapsulated siRNA in the liposomes could be effectively protected from serum degradation. Also, enhanced cell binding and intracellular uptake of siRNA in the doxorubicin-resistant human ova- rian cancer cell lines SKOV3/A were found in RGD-Lipo-siRNA preparation as compared to that of unmodified cationic lipsomes （Lipo-siRNA）. Using the post-insertion method for RGD modification, lysosome release of siRNA in pRGD-Lipo-siRNA was improved. From flow cytometry, significant increase of doxorubicin accumulation was observed in the SKOV3/A cells treated with pRGD-Lipo-siRNA targeting human MDR1 gene. In vitro cytotoxicity assay showed that the significant cell growth inhibition was achieved in the SKOV3/A cells after treating with the combined use of siRNA and doxorubicin. In conclusions, postinserted RGD modified lipoplex, pRGD-Lipo-siRNA, was successfully used for siRNA transfection and achieved drug resistance reversal in human ovarian cancer SKOV3/A （doxorubicin-resistant） cells. It suggested that this liposomes might be a potential vehicle for siRNA delivery in vivo.展开更多
Cationic lipids have been applied to siRNA delivery for tumor therapeutics. However, the excess positive charges of these nanoplexes may lead to high cytotoxicity and nonnegligible immunogenicity both in vitro and in ...Cationic lipids have been applied to siRNA delivery for tumor therapeutics. However, the excess positive charges of these nanoplexes may lead to high cytotoxicity and nonnegligible immunogenicity both in vitro and in vivo, which limited the applications of gene drugs. We constructed multi-component lipoplex to delivery 3＇,3＂-bis-peptide-siRNA conjugate （pp-siRNA） by the treatment of melanoma. Based on the previous studies that the gemini lipid （CLD） encapsulated pp-siRNA, a novel neutral cytosin-l-yl- lipid （DNCA） was considered to replace a certain ration of CLD by hydrogen bonds and ~t-n stacking for reducing the cytotoxicity. It similarly retained in both the loading efficiency and targeted mRNA inhibition when DNCA was accounted for 40% in the lipoplex, with lower toxicity. Moreover, CLD/DNCA/pp-siRNA nanoplex could be uptake in A375 cells and internalized mainly by macropinocytosis and caveolin-mediated endocytosis. Besides, 90% CLD/DNCA/pp-siRNA nanoplexes presented the highest efficient knockdown for the mutant B-RAF mRNA （-80%）. All the results demonstrated that the mixed cationic and neutral lipids could efficiently realize the delivery of pp-siRNA and had potential application for cancer therapy.展开更多
The rheology of the cationic guar （CG） solution was measured and the effects of potassium oleate （KOA） upon the rheological properties of CG solution were studied. The steady shear viscosity measurement has shown ...The rheology of the cationic guar （CG） solution was measured and the effects of potassium oleate （KOA） upon the rheological properties of CG solution were studied. The steady shear viscosity measurement has shown that the viscosity of CG solution increased dramatically in the presence of KOA. The viscosity enhancement of KOA upon CG solution can be approximate three orders in magnitude. The gel-like formation of CG solution is observed at the high concentration of KOA. The excess addition of KOA results in the phase separation of CG solution. The oscillatory rheological measurement has shown that the crossover modulus Gc （corresponding to either storage modulus G＇ or loss modulus G＇＇ at the frequency wc where G＇ equals G＇＇） for CG solution, decreases with the increasing the concentration of KOA in solution. On the other hand, the apparent relaxation time 7-app （=1/wc） increases with increasing the concentration of KOA in solution. Our experimental results suggest that for surfaetant such as KOA which has a stronger tendency to form micelles in solution, the cooperative hydrophobic interaction of polymer bound to surfactants is less necessary to the formation of aggregates in solution, especially at the high concentration of surfactants. In fact, with the increase of the concentration of KOA, the number of the aggregates which associate polymer together decreases whereas the intensity of these aggregates increases. The effect of temperature upon the aggregation is also significant. With the increase of temperature, the number of the aggregates increases whereas the intensity of these aggregates decreases, probably because the ionization of KOA increases at high temperature.展开更多
This study aimed to investigate the effects of cationic liposomes containing different cationic lipids （DC-Chol and DOTAP） and different pegylation ratios on siRNA transfection in human U251 glioma cells. The data s...This study aimed to investigate the effects of cationic liposomes containing different cationic lipids （DC-Chol and DOTAP） and different pegylation ratios on siRNA transfection in human U251 glioma cells. The data showed that the transfection efficiency of DOTAP was much higher than that of DC-Chol and PEG at 2 mol% enhanced cellular uptake of siRNA. Cationic liposome-siRNA complexes with particle size around 100 nm were prepared. PEG modification could efficiently stabilize the liposome in the presence of serum, which might protect the siRNA from serum degradation and prolong the circulation time in vivo. Efficient intracellular uptake and lysosome release of siRNA in human U251 glioma cells were observed for pegylated DOTAP-based lipososomes compared with the control transfection reagent lipofectamine 2000. The results demonstrated that this cationic liposome might be a potential vehicle for the in vivo delivery of siRNA.展开更多
文摘Posaconazole(PCZ)is a broad-spectrum anti-fungal drug approved by FDA and currently used off-label for the treatment of fungal keratitis(FK).Although ocular route serves as the most bioavailable route for treating FK,delivery of PCZ to the eye remains a challenge due to poor permeation though the cornea and rapid elimination from the eye.Here we outline a comprehensive formulation development process,beginning with in silico studies,progressing through in vitro evaluations,and ultimately achieving therapeutic benefits in vivo.We report modified niosome-like surfactant vesicles,hereafter termed as NioTherms,formulated using a novel and simple heat-mix method,encapsulating PCZ for ocular administration in the form of an in situ gel.Excipient screening performed using in silico simulations highly correlate with in vitro studies(R^(2)=0.77),guiding optimization by Quality by Design(QbD)approach for encapsulating PCZ in NioTherms resulting in particles with an average size of 180.7±2.3 nm,zeta potential of +27.5±2.2 mV and entrapment efficiency of 87.6%±1.7%.A 2-fold increase in both mucin binding and cellular uptake indicates a functional role of positive surface charge in enhancingmucoadhesive properties of PCZ-NioTherms.In an in vivo murine ocular keratitis model,we demonstrate a 2-fold enhancement in trans-corneal permeability of PCZ-NioTherms and a 3-fold reduction in fungal burden compared to the control standard of care,the PCZ solution.Owing to a facile formulation process,we anticipate that PCZ-NioTherms would serve as a clinically translatable and patient compliant therapeutic intervention for treating FK.
基金supported by the Basic Science Research Program(RS-2024-00344021,RS-2023-00261543,and RS-202300257666)through the National Research Foundation of Korea(NRF),the National Research Council of Science(000)Korea Institute for Advancement of Technology(KIAT)grant funded by the Korea Government(MOTIE)(RS-2024-00420590,HRD Program for Industrial Innovation)The computational resources were provided by KITSI(KSC-2024-CRE-0143)。
文摘Despite the growing interest in fast-cha rging solid-state lithium(Li)-metal batteries(SSLMBs),their practical implementation has yet to be achieved,primarily due to an incomplete understanding of the disparate and often conflicting requirements of the bulk electrolyte and the electrode-electrolyte interphase.Here,we present a weakly coordinating cationic polymer electrolyte(WCPE)specifically designed to regulate the Li^(+)coordination structure,thereby enabling fast-charging SSLMBs.The WCPE comprises an imidazolium-based polycationic matrix combined with a succinonitrile(SN)-based highconcentration electrolyte.Unlike conventional neutral polymer matrices,the polycationic matrix in the WCPE competes with Li^(+)for interactions with SN,weakening the original coordination between SN and Li^(+).This modulation of SN-Li^(+)interaction improves both Li^(+)conductivity of the WCPE(σ_(Li^(+))=1.29mS cm^(-1))and redox kinetics at the electrode-electrolyte interphase.Consequently,SSLMB cells(comprising LiFePO_(4)cathodes and Li-metal anodes)with the WCPE achieve fast-charging capability(reaching over 80%state of charge within 10 min),outperforming those of previously reported polymer electrolytebased SSLMBs.
基金supported by the National Natural Science Foundation of China(U22A20429 and 22308103)Shanghai Pilot Program for Basic Research(22TQ1400100-13)+2 种基金Postdoctoral Fellowship Program of CPSF(GZB20230214)China Postdoctoral Science Foundation(2023M731083)the Fundamental Research Funds for the Central Universities.
文摘Developing cost-effective single-crystalline Ni-rich Co-poor cathodes operating at high-voltage is one of the most important ways to achieve higher energy Li-ion batteries. However, the Li/O loss and Li/Ni mixing under high-temperature lithiation result in electrochemical kinetic hysteresis and structural instability. Herein, we report a highly-ordered single-crystalline LiNi0.85Co0.05Mn0.10O2(NCM85) cathode by doping K+and F-ions. To be specific, the K-ion as a fluxing agent can remarkably decrease the solid-state lithiation temperature by ~30°C, leading to less Li/Ni mixing and oxygen vacancy. Meanwhile, the strong transitional metal(TM)-F bonds are helpful for enhancing de-/lithiation kinetics and limiting the lattice oxygen escape even at 4.5 V high-voltage. Their advantages synergistically endow the single-crystalline NCM85 cathode with a very high reversible capacity of 222.3 mAh g-1. A superior capacity retention of 91.3% is obtained after 500 times at 1 C in pouch-type full cells, and a prediction value of 75.3% is given after cycling for 5000 h. These findings are reckoned to expedite the exploitation and application of high-voltage single-crystalline Ni-rich cathodes for next-generation Li-ion batteries.
基金the National Key Research and Development Program of China(No.2021YFB3800900)National Natural Science Foundation of China(No.51925305)the talent cultivation project Funds for the Innovation Laboratory for Sciences and Technologies of Energy Materials of Fujian Province(No.HRTP[2022]52)。
文摘The occurrence,development,and metastasis of tumors often entail abnormal expression of genetic substances.Monitoring and regulating changes in intracellular nucleic acid substances hold promise for achieving accurate tumor diagnosis and effective treatment.However,the effectiveness of integrated tumor diagnosis and treatment based on functional nucleic acids still needs to be improved.In this study,we engineered a multifunctional nucleic acid delivery system grounded in a cationic covalent organic framework carrier.This system not only showcases effective gene silencing but also boasts high sensitivity in detecting miR21 levels within tumor cells,enabling real-time monitoring of tumor gene therapy efficacy.The construction of this integrated functional nucleic acid delivery platform provides new ideas for precise tumor detection and effective tumor treatment.
基金financially supported by the National Natural Science Foundation of China(No.52373011)。
文摘Living cationic polymerization of 4-acetoxystyrene(STO)was conducted in CH_(2)Cl_(2) at-15℃ using a dicumyl chloride(DCC)/SnCl_(4)/nBu_(4)NBr initiating system.Impurity moisture initiation was inhibited by adding proton trap 2,6-di-tert-butylpyridine(DTBP),and the controlled initiation of DCC was confirmed by ^(1)H nuclear magnetic resonance(^(1)H-NMR)spectroscopy and matrix-assisted laser desorption ionization time-offlight mass(MALDI-TOF-MS)spectrometry.The polymerization kinetics were analyzed to for optimizing the polymerization rate.Allyl-telechelic PSTOs(allyl-PSTO-allyl)with molecular weight(Mn)range of 3540–7800 g/mol and narrow molecular weight dispersity(Mw/Mn)about 1.25 were prepared through nucleophilic substitution with allyltrimethylsilane(ATMS)at approximately 40%monomer conversion.The experimental results indicate that the substitution efficiency of ATMS increased with higher ATMS concentration,temperature,and extended reaction time.Nearly unity ally-functionality for allyl-PSTO-allyl was achieved by adding sufficient SnCl_(4) prior to the substitution.
基金National Natural Science Foundation of China (61761047 and 41876055)Program for Innovative Research Team (in Science and Technology) in University of Yunnan Province。
文摘Aqueous zincion batteries are highly favored for grid-level energy storage owing to their low cost and high safety,but their practical application is limited by slow ion migration.To address this,a strategy has been developed to create a cation-accelerating electric field on the surface of the cathode to achieve ultrafast Zn^(2+)diffusion kinetics.By employing electrodeposition to coat MoS_(2)on the surface of BaV_(6)O_(16)·3H_(2)O nanowires,the directional builtin electric field generated at the heterointerface acts as a cation accelerator,continuously accelerating Zn^(2+)diffusion into the active material.The optimized Zn^(2+)diffusion coefficient in CC@BaV-V_(6)O_(16)·3H_(2)@MoS_(2)(7.5×10^(8)cm^(2)s^(-1)) surpasses that of most reported V-based cathodes.Simultaneously,MoS_(2)serving as a cathodic armor extends the cycling life of the Zn-CC@BaV_(6)O_(16)·3H_(2)@MoS_(2)full batteries to over 10000 cycles.This work provides valuable insights into optimizing ion diffusion kinetics for high-performance energy storage devices.
基金financially supported by the Natural Science Foundation of Jilin Province Science and Technology Department(No.20230101221JC)the National Natural Science Foundation of China(Nos.52173115,52073278,52203189)the Research Foundation for Advanced Talents of Xiamen University of Technology(Nos.5010423019,YKJ22052R)。
文摘It is well known that cationic polymers have excellent antimicrobial capacity accompanied with high biotoxicity,to reduce biotoxicity needs to decrease the number of cationic groups on polymers,which will influence antimicrobial activity.It is necessary to design a cationic polymer mimic natural antimicrobial peptide with excellent antibacterial activity and low toxicity to solve the above dilemma.Here,we designed and prepared a series of cationic poly(β-amino ester)s(PBAEs)with different cationic contents,and introducing hydrophobic alkyl chain to adjust the balance between antimicrobial activity and biotoxicity to obtain an ideal antimicrobial polymer.The optimum one of synthesized PBAE(hydrophilic cationic monomer:hydrophobic monomer=5:5)was screened by testing cytotoxicity and minimum inhibitory concentration(MIC),which can effectively kill S.aureus and E.coli with PBAE concentration of15μg/m L by a spread plate bacteriostatic method and dead and alive staining test.The way of PBAE killing bacterial was destroying the membrane like natural antimicrobial peptide observed by scanning electron microscopy(SEM).In addition,PBAE did not exhibit hemolysis and cytotoxicity.In particular,from the result of animal tests,the PBAE was able to promote healing of infected wounds from removing mature S.aureus and E.coli on the surface of infected wound.As a result,our work offers a viable approach for designing antimicrobial materials,highlighting the significant potential of PBAE polymers in the field of biomedical materials.
基金National Natural Science Foundation of China (No.52202046)Natural Science Foundation of Shaanxi Province (No.2021JQ-034)。
文摘Lithium-rich layered oxides (LLOs) are increasingly recognized as promising cathode materials for nextgeneration high-energy-density lithium-ion batteries (LIBs).However,they suffer from voltage decay and low initial Coulombic efficiency (ICE) due to severe structural degradation caused by irreversible O release.Herein,we introduce a three-in-one strategy of increasing Ni and Mn content,along with Li/Ni disordering and TM–O covalency regulation to boost cationic and anionic redox activity simultaneously and thus enhance the electrochemical activity of LLOs.The target material,Li_(1.2)Ni_(0.168)Mn_(0.558)Co_(0.074)O_(2)(L1),exhibits an improved ICE of 87.2%and specific capacity of 293.2 mA h g^(-1)and minimal voltage decay of less than 0.53 m V cycle-1over 300 cycles at 1C,compared to Li_(1.2)Ni_(0.13)Mn_(0.54)Co_(0.13)O_(2)(Ls)(274.4 mA h g^(-1)for initial capacity,73.8%for ICE and voltage decay of 0.84 mV/cycle over 300 cycles at 1C).Theoretical calculations reveal that the density of states (DOS) area near the Fermi energy level for L1 is larger than that of Ls,indicating higher anionic and cationic redox reactivity than Ls.Moreover,L1 exhibits increased O-vacancy formation energy due to higher Li/Ni disordering of 4.76%(quantified by X-ray diffraction Rietveld refinement) and enhanced TM–O covalency,making lattice O release more difficult and thus improving electrochemical stability.The increased Li/Ni disordering also leads to more Ni^(2+)presence in the Li layer,which acts as a pillar during Li+de-embedding,improving structural stability.This research not only presents a viable approach to designing low-Co LLOs with enhanced capacity and ICE but also contributes significantly to the fundamental understanding of structural regulation in high-performance LIB cathodes.
基金financially supported by the General Research Fund(CityU 11315622 and CityU 11310123)National Natural Science Foundation(NSFC 52372229 and NSFC 52172241)+3 种基金Green Tech Fund(GTF202220105)Guangdong Basic and Applied Basic Research Foundation(2024A1515011008)City University of Hong Kong(No.9020002)the Shenzhen Research Institute of City University of Hong Kong.
文摘The development of flexible zinc-ion batteries(ZIBs)faces a threeway trade-off among the ionic conductivity,Zn^(2+)mobility,and the electrochemical stability of hydrogel electrolytes.To address this challenge,we designed a cationic hydrogel named PAPTMA to holistically improve the reversibility of ZIBs.The long cationic branch chains in the polymeric matrix construct express pathways for rapid Zn^(2+)transport through an ionic repulsion mechanism,achieving simultaneously high Zn^(2+)transference number(0.79)and high ionic conductivity(28.7 mS cm−1).Additionally,the reactivity of water in the PAPTMA hydrogels is significantly inhibited,thus possessing a strong resistance to parasitic reactions.Mechanical characterization further reveals the superior tensile and adhesion strength of PAPTMA.Leveraging these properties,symmetric batteries employing PAPTMA hydrogel deliver exceeding 6000 h of reversible cycling at 1 mA cm^(−2) and maintain stable operation for 1000 h with a discharge of depth of 71%.When applied in 4×4 cm2 pouch cells with MnO_(2) as the cathode material,the device demonstrates remarkable operational stability and mechanical robustness through 150 cycles.This work presents an eclectic strategy for designing advanced hydrogels that combine high ionic conductivity,enhanced Zn^(2+)mobility,and strong resistance to parasitic reactions,paving the way for long-lasting flexible ZIBs.
基金Project(51304085)supported by the National Natural Science Foundation of ChinaProject(GJJ12363)supported by the Education Department of Jiangxi Province,ChinaProject(20142BAB216021)supported by the Natural Science Foundation of Jiangxi Province,China
文摘The flotation of diaspore and three kinds of silicate minerals, including kaolinite, illite and pyrophyllite, using an organosilicon cationic surfactant (TAS101) as collector and starch as depressant was investigated. The results show that both diaspore and aluminosilicate minerals float readily with organosilicon cationic collector TAS101 at pH values of 4 to 10. Starch has a strong depression effect for diaspore in the alkaline pH region but has little influence on the flotation of aluminosilicate minerals. It is possible to separate diaspore from aluminosilicate minerals using the organosilicon cationic collector and starch depressant. Further studies of bauxite ore flotation were also conducted, and the reverse flotation separation process was adopted. The concentrates with the mass ratio of Al2O3 to SiO2 of 9.58 and Al2O3 recovery of 83.34% are obtained from natural bauxite ore with the mass ratio of Al2O3 to SiO2 of 6.1 at pH value of 11 using the organosilicon cationic collector and starch depressant.
基金Project(2013AA064102)supported by the High-tech Research and Development Program of ChinaProject(51004114)supported by the National Natural Science Foundation of China+1 种基金Project(2007B52)supported by the Foundation for the Author of National Excellent Doctoral Dissertation of ChinaProject(NCEP-08-0568)supported by the Program for New Century Excellent Talents in Chinese University
文摘Gemini quaternary ammonium salt surfactants, butane-a, co-bis（dimethyl dodeculammonium bromide） （BDDA） ethane-a, fl-bis（dimethyl dodeculammonium bromide） （EDDA） were adopted to comparatively study the flotation behaviors of kaolinite, pyrophyllite and illite. It was found that three silicate minerals all exhibited good floatability with Gemini cationic surfactants as collectors over a wide pH range, while BDDA showed a stronger collecting power than EDDA. FTIR spectra and zeta potential analysis indicated that the mechanism of adsorption of Gemini collector molecules on three silicate minerals surfaces was almost identical for the electronic attraction and hydrogen bonds effect. The theoretically obtained results of density functional theory （DFT） at B3LYP/6-31G （d） level demonstrated the stronger collecting power of BDDA presented in the floatation test and zeta potential measurement.
文摘The cationic guar （CG） is synthesized and the rheological behavior of aqueous solutions of CG in the presence of sodium dodecyl sulfate （SDS） is studied in detail. The steady viscosity measurements show that the zero shear viscosity enhancement can be almost 3 orders of magnitude as the concentration of SDS increases from 0 to 0.043%. The gel-like formation is observed as the concentration of SDS is greater than 0.016%. The oscillatory rheological measurements of CG solutions in the presence of SDS show that the crossover modulus is almost independent of the concentration of SDS whereas the apparent relaxation time increases swiftly upon increasing the concentration of SDS. The experimental results indicate that the strength rather than the number of the cross-links is greatly affected by SDS molecules. The mechanism concerning the effect of SDS upon the rheology of CG solutions can be coined by the two-stage model. Before the formation of cross-links at the critical concentration, the electrostatic interaction between SDS and cationic site of CG chains plays a key role and the SDS molecules bind to CG chains through the electrostatic interaction. After the formation of cross-links at the concentration greater than the critical concentration, the cooperative hydrophobic interaction become dominant and SDS molecules bind to the cross-links through the hydrophobic interaction. The theological behavior of aqueous solutions of CG in the presence of SDS is chiefly determined by the micelle-like cross-links between CG chains. In fact, the flow activation energy of CG solution, obtained from the temperature dependence of the apparent relaxation time, falls in the range of transferring a hydrophobic tail of SDS from the micelle to an aqueous environment.
基金supported by the Scientific Research and Technology Development Project of China National Petroleum Corporation(Grant Nos.2024ZG50,2022DQ03-03)the National Natural Science Foundation of China(Grant Nos.52372252)the Science and Technology Innovation Program of Hunan Province(Grant Nos.2024RC1022).
文摘Dendrite growth represents one of the most significant challenges that impede the development of aqueous zinc-ion batteries.Herein,Gd^(3+)ions are introduced into conventional electrolytes as a microlevelling agent to achieve dendrite-free zinc electrodeposition.Simulation and experimental results demonstrate that these Gd^(3+)ions are preferentially adsorbed onto the zinc surface,which enables dendritefree zinc anodes by activating the microlevelling effect during electrodeposition.In addition,the Gd^(3+)additives effectively inhibit side reactions and facilitate the desolvation of[Zn(H_(2)O)_(6)]^(2+),leading to highly reversible zinc plating/stripping.Due to these improvements,the zinc anode demonstrates a significantly prolonged cycle life of 2100 h and achieves an exceptional average Coulombic efficiency of 99.72%over 1400 cycles.More importantly,the Zn//NH_(4)V_(4)O_(10)full cell shows a high capacity retention rate of 85.6%after 1000 cycles.This work not only broadens the application of metallic cations in battery electrolytes but also provides fundamental insights into their working mechanisms.
基金supported by the Science and Technology Department of Zhejiang Province under Grant No. 2010C31040the financial support of Zhejiang Provincial Natural Science Foundation of China(No. Y4100152)Zhejiang University of Technology Natural Science Foundation(No.20100202)
文摘Cationic fluorinated acrylate latex was prepared via semi-continuous emulsion copolymerization of cationic monomer and other monomers. The resultant latex and its film were characterized with dynamic light scattering detector and contact angle meter. Influences of amount of DMDAAC on the properties of resultant latex and its film were investigated in detail. Results show that the particle size of the latex has the minimum value knd the zeta potential of the latex is increased when the amount of DMDAAC is increased. In addition, the particle size of the latex is unimodal distribution when the amount of DMDAAC is not more than 2.5%. However, the particle size of the latex is bimodal distribution when the amount of DMDAAC is more than 2.5%. The contact angle is varied slightly with the increase of amount of DMDAAC when it is not more than 2.5%. Nevertheless, the contact angle is decreased with the increase of the amount of DMDAAC when it is more than 2.5%.
基金supported by the National Natural Science Foundation of China(Nos.21174096,21274100 and 21234005)the Project of International Cooperation of the Ministry of Science and Technology of China(No.2011DFA50530)the Priority Academic Program Development of Jiangsu Higher Education Institutions(PAPD)
文摘In this work, a fluorescent monomer 2-（9-carbazolyl） ethyl vinyl ether（CEVE） was synthesized in our lab, and its photo-induced living cationic copolymerization behavior with isobutyl vinyl ether（IBVE） was investigated in detail using diphenyliodonium chloride（DPICl）/2,2-dimethoxy-2-phenylacetophenone（DMPA） and zinc bromide（Zn Br2） initiating system in dichloromethane solution at 5 °C, -5 °C, and -15 °C, respectively. The living nature of this copolymerization system was confirmed by adding fresh comonomer method after the copolymerization almost finished. In addition, the obtained fluorescent copolymer poly（IBVE-co-CEVE） has a low glass transition temperature（Tg）, below -10 °C.
文摘Introduction Cationic starches are a series of products of which various sorts with different properties and usages can all be produced via cationic reactions by using different types of etherification agents under different conditions. As an additive and strengthening agent,
基金National Natural Science Foundation of China(Grant No.30701056)Foundation of MOST(973 Program,Grant No.2007CB935801)+1 种基金Beijing Natural Science Foundation of China(Grant No.7083112)Doctoral Foundation of Ministry of Education of China(Grant No.20070001813).
文摘In this study, the novel RGD-modified stabilized cationic liposomes were developed as the delivery vehicle for siRNA targeting human MDR1 gene. The complex of cationic liposomes and siRNA, RGD-Lipo-siRNA, was prepared with a narrow size distribution below 200 nm. It was shown that the encapsulated siRNA in the liposomes could be effectively protected from serum degradation. Also, enhanced cell binding and intracellular uptake of siRNA in the doxorubicin-resistant human ova- rian cancer cell lines SKOV3/A were found in RGD-Lipo-siRNA preparation as compared to that of unmodified cationic lipsomes （Lipo-siRNA）. Using the post-insertion method for RGD modification, lysosome release of siRNA in pRGD-Lipo-siRNA was improved. From flow cytometry, significant increase of doxorubicin accumulation was observed in the SKOV3/A cells treated with pRGD-Lipo-siRNA targeting human MDR1 gene. In vitro cytotoxicity assay showed that the significant cell growth inhibition was achieved in the SKOV3/A cells after treating with the combined use of siRNA and doxorubicin. In conclusions, postinserted RGD modified lipoplex, pRGD-Lipo-siRNA, was successfully used for siRNA transfection and achieved drug resistance reversal in human ovarian cancer SKOV3/A （doxorubicin-resistant） cells. It suggested that this liposomes might be a potential vehicle for siRNA delivery in vivo.
基金The National Natural Science Foundation of China(Grant No.21778006 and 20932001)the Ministry of Science and Technology of China(Grant No.2012AA022501)
文摘Cationic lipids have been applied to siRNA delivery for tumor therapeutics. However, the excess positive charges of these nanoplexes may lead to high cytotoxicity and nonnegligible immunogenicity both in vitro and in vivo, which limited the applications of gene drugs. We constructed multi-component lipoplex to delivery 3＇,3＂-bis-peptide-siRNA conjugate （pp-siRNA） by the treatment of melanoma. Based on the previous studies that the gemini lipid （CLD） encapsulated pp-siRNA, a novel neutral cytosin-l-yl- lipid （DNCA） was considered to replace a certain ration of CLD by hydrogen bonds and ~t-n stacking for reducing the cytotoxicity. It similarly retained in both the loading efficiency and targeted mRNA inhibition when DNCA was accounted for 40% in the lipoplex, with lower toxicity. Moreover, CLD/DNCA/pp-siRNA nanoplex could be uptake in A375 cells and internalized mainly by macropinocytosis and caveolin-mediated endocytosis. Besides, 90% CLD/DNCA/pp-siRNA nanoplexes presented the highest efficient knockdown for the mutant B-RAF mRNA （-80%）. All the results demonstrated that the mixed cationic and neutral lipids could efficiently realize the delivery of pp-siRNA and had potential application for cancer therapy.
文摘The rheology of the cationic guar （CG） solution was measured and the effects of potassium oleate （KOA） upon the rheological properties of CG solution were studied. The steady shear viscosity measurement has shown that the viscosity of CG solution increased dramatically in the presence of KOA. The viscosity enhancement of KOA upon CG solution can be approximate three orders in magnitude. The gel-like formation of CG solution is observed at the high concentration of KOA. The excess addition of KOA results in the phase separation of CG solution. The oscillatory rheological measurement has shown that the crossover modulus Gc （corresponding to either storage modulus G＇ or loss modulus G＇＇ at the frequency wc where G＇ equals G＇＇） for CG solution, decreases with the increasing the concentration of KOA in solution. On the other hand, the apparent relaxation time 7-app （=1/wc） increases with increasing the concentration of KOA in solution. Our experimental results suggest that for surfaetant such as KOA which has a stronger tendency to form micelles in solution, the cooperative hydrophobic interaction of polymer bound to surfactants is less necessary to the formation of aggregates in solution, especially at the high concentration of surfactants. In fact, with the increase of the concentration of KOA, the number of the aggregates which associate polymer together decreases whereas the intensity of these aggregates increases. The effect of temperature upon the aggregation is also significant. With the increase of temperature, the number of the aggregates increases whereas the intensity of these aggregates decreases, probably because the ionization of KOA increases at high temperature.
基金National Natural Science Foundation of China (Grant No.30701056)Foundation of MOST(973 Program,Grant No.2007CB935801)+1 种基金Beijing Natural Science Foundation of China (Grant No.7083112)Doctoral Fund of Ministry of Education of China(Grant No.20070001813).
文摘This study aimed to investigate the effects of cationic liposomes containing different cationic lipids （DC-Chol and DOTAP） and different pegylation ratios on siRNA transfection in human U251 glioma cells. The data showed that the transfection efficiency of DOTAP was much higher than that of DC-Chol and PEG at 2 mol% enhanced cellular uptake of siRNA. Cationic liposome-siRNA complexes with particle size around 100 nm were prepared. PEG modification could efficiently stabilize the liposome in the presence of serum, which might protect the siRNA from serum degradation and prolong the circulation time in vivo. Efficient intracellular uptake and lysosome release of siRNA in human U251 glioma cells were observed for pegylated DOTAP-based lipososomes compared with the control transfection reagent lipofectamine 2000. The results demonstrated that this cationic liposome might be a potential vehicle for the in vivo delivery of siRNA.
