Targeted anti-cancer therapy: Co-delivery of VEGF siRNA and Phenethyl isothiocyanate (PEITC) via cRGD-modified lipid nanoparticles for enhanced anti-angiogenic efficacy

Anti-tumor angiogenesis therapy, targeting the suppression of blood vessel growth in tumors, presents a potent approach in the battle against cancer. Traditional therapies have primarily concentrated on single-target techniques, with a specific emphasis on targeting the vascular endothelial growth factor, but have not reached ideal therapeutic efficacy. In response to this issue, our study introduced a novel nanoparticle system known as CS-siRNA/PEITC&L-cRGD NPs. These chitosan-based nanoparticles have been recognized for their excellent biocompatibility and ability to deliver genes. To enhance their targeted delivery capability, they were combined with a cyclic RGD peptide (cRGD). Targeted co-delivery of gene and chemotherapeutic agents was achieved through the use of a negatively charged lipid shell and cRGD, which possesses high affinity for integrin αvβ3 overexpressed in tumor cells and neovasculature. In this multifaceted approach, co-delivery of VEGF siRNA and phenethyl isothiocyanate (PEITC) was employed to target both tumor vascular endothelial cells and tumor cells simultaneously. The co-delivery of VEGF siRNA and PEITC could achieve precise silencing of VEGF, inhibit the accumulation of HIF-1α under hypoxic conditions, and induce apoptosis in tumor cells. In summary, we have successfully developed a nanoparticle delivery platform that utilizes a dual mechanism of action of anti-tumor angiogenesis and pro-tumor apoptosis, which provides a robust and potent strategy for the delivery of anti-cancer therapeutics.

Self-organization of Gold Nanoparticles Protected by 9-(5-Thiopentyl)-carbazole

Through the reduction of [AuCl4] by aqueous sodium borohydride in the presence of 9-(5-thiopentyl)-carbazole, the gold nanoparticles has been prepared and characterized.

SYNTHESIS AND CHARACTERIZATION OF STRUCTURALLY WELL-DEFINED POLYMER-INORGANIC HYBRID NANOPARTICLES VIA ATRP

Atom transfer radical polymerization (ATRP) using cuprous chloride/2,2'-bipyridine (bipy) was applied to graft polymerization of styrene on the surface of silica nanoparticles to synthesize polymer-inorganic hybrid nanoparticles, 2-(4Chloromethylphenyl) ethyltriethoxysilane (CTES) was immobilized on the surface of silica nanoparticles through condensation reaction of the silanol groups on silica with triethoxysilane group of CTES. Then ATRP of St was initiated by this surface-modified silica nanoparticles bearing benzyl chloride groups, and formed PSt graft chains on the surface of silica nanoparticles. The thickness of the graft chains increased with reaction time. End group analysis confirmed the occurrence of ATRP. Thermal analysis indicated that thermal stabilization of these resulting hybrid nanoparticles also increases with polymerization conversion. The results above show that this 'grafting from' reaction could be used for the preparation of polymer-inorganic hybrid nanoparticles with controlled structure of the polymer's end groups.

Preparation of Elemental Tellurium Nanoparticles-Sucrose Sol and Its Antioxidant Activity in Vitro

The elemental tellurium nanoparticles （TeNPs） - sucrose sol was prepared by the reaction of sodium tellurite with ascorbic acid in sucrose aqueous solution. The results indicated that TeNPs were dispersion excellent in the TeNPs - sucrose sol and the morphology of TeNPs was needle-like with about 70 nm in width and 500 nm in length. The antioxidant activity of the TeNPs - sucrose sol in vitro was estimated by pyrogallol autoxidation method, Fenton method and oxygen radical absorbance capacity （ORAC） assay. The results showed that a certain amount of TeNPs - sucrose sol could effectively scavenge superoxide anion free radical and hydroxyl free radical with scavenging rates of 73 % and 57 %, respectively. ORAC assay was used to measure the total antioxidant capacity of TeNPs - sucrose sol. The order of ORAC values was 2.25 μmol.L-1 TeNPs - 0.025 % sucrose sol 〉 0.025 % sucrose 〉 2.25 μmol.L-1 Na2TeO3 〉 1.63 μmol.L-1 ascorbic acid. The results suggested that the TeNPs - sucrose sol had the excellent antioxidant activity and TeNPs were the dominating contributors to antioxidant capacity of the TeNPs - sucrose sol.

Interaction of N-(2-Methyl Thio Phenyl)-2-Hydroxy-1-Naphthaldimine with Tin Dioxide Nanoparticles: A Spectroscopic Approach

The interaction of N-(2-methyl thiophenyl)-2-hydroxy-1-naphthaldimine (NMTHN) with tin dioxide nanoparticles (SnO2 NPs) has been investigated by spectroscopic tools such as absorption and fluorescence spectroscopy. Absorption spectroscopy reveals the formation of ground state complex. Fluorescence spectroscopy has been used to study the signatures of fluorescence quenching. SnO2 NPs are found to quench the intrinsic fluorescence of NMTHN via static and dynamic quenching. The deviation from linearity in the Stern-Volmer plot has been observed.

Simulation of the Brownian coagulation of nanoparticles with initial bimodal size distribution via moment method

The Brownian coagulation of nanoparticles with initial bimodal size distribution, i.e., mode i and j, is numerically studied using the moment method. Evolutions of particle number concentration, geometric average diameter and geometric standard deviation are given in the free molecular regime, the continuum regime, the free molecular regime and transition regime, the free molecular regime and continuum regime, respectively. The results show that, both in the free molecular regime and the continuum regime, the num- ber concentration of mode i and j decreases with increasing time. The evolutions of particle geometric average diameter with different initial size distribution are quite different. Both intra-modal and inter-modal coagulation finally make the polydispersed size distribution become monodispersed. As time goes by, the size distribution with initial bimodal turns to be unimoda/and shifts to a larger particle size range. In the free molecular regime and transition regime, the inter- modal coagulation becomes dominant when the number concentrations of mode i and j are of the same order. The effects of the number concentration of mode i and mode j on the evolution of geometric average diameter of mode j are negligible, while the effects of the number concentration of mode j on the evolution of geometric average diameter of mode j is distinct. In the free molecular regime and continuum regime, the higher the initial number concentration of mode j, the more obvious the variation of the number concentration of mode i.

Synthesis and Characterization of Ag Nanoparticles Addition on BPSCCO Superconducting Thin Films

The growth of epitaxial Ag nanoparticles doped (Bi, Pb)-2223 thin films on Si (111) substrates by pulsed laser deposition (PLD) and post-deposition oxygen annealing have been achieved. The phase identification and gross structural characteristics of synthesized films explored through X-ray diffractometer reveal that all the samples crystallize in orthorhombic structure. DC electrical resistivity measurements were done by the standard four-probe method and the results showed improvement in Tc by increasing Ag nanoparticles to 1.0 wt% which had a maximum enhancement in Tc for all investigated films. The surface morphology investigated through scanning electron microscope (SEM) and atomic force microscopy (AFM) results showed that an increase in Tc with the appropriate Ag nanoparticles addition in the samples is associated with the enhancement of Bi (Pb)-2223 phase formation.

Thermo-sensitive polymer nanospheres as a smart plugging agent for shale gas drilling operations

Emulsifier-free poly（methyl methacrylate-styrene） [P（MMA-St）] nanospheres with an average particle size of 100 nm were synthesized in an isopropyl alcoholwater medium by a solvothermal method. Then, through radical graft copolymerization of thermo-sensitive mono- mer N-isopropylacrylamide （NIPAm） and hydrophilic monomer acrylic acid （AA） onto the surface of P（MMA- St） nanospheres at 80 ℃, a series of thermo-sensitive polymer nanospheres, named SD-SEAL with different lower critical solution temperatures （LCST）, were prepared by adjusting the mole ratio of NIPAm to AA. The products were characterized by Fourier transform infrared spectroscopy, transmission electron microscopy, thermogravimetric analysis, particle size distribution, and specific surface area analysis. The temperature-sensitive behavior was studied by light transmittance tests, while the sealing performance was investigated by pressure transmission tests with Lungmachi Formation shales. The experimental results showed that the synthesized nanoparticles are sensitive to temperature and had apparent LCST values which increased with an increase in hydrophilic monomer AA. When the temperature was higher than its LCST value, SD- SEAL played a dual role of physical plugging and chemical inhibition, slowed down pressure transmission, and reduced shale permeability remarkably. The plugged layer of shale was changed to being hydrophobic, which greatly improved the shale stability

Nanoparticle nucleation and coagulation in a mixing layer

Numerical simulation of nanoparticle nucleation and coagulation in a mixing layer with sulfuric acid vapor binary system is performed using the large eddy simulation and the direct quadrature method of moment. The distributions of number concentration, volume concentration, and average diameter of nanoparticles are obtained. The results show that the coherent structures have an important effect on the distributions of number concentration, volume concentration and average diameter of nanoparticles via continuously transporting and diffusing the nanoparticles to the area of low particle concentration. In the streamwise direction, the number concentration of nanoparticles decreases, while the volume concentration and the average diameter increase. The distributions of number concentration, volume concentration and average diameter of nanoparticles are spatially inhomogeneous. The characteristic time of nucleation is shorter than that of coagulation. The nucleation takes place more easily in the area of low temperature because where the number concentration of nanoparticles is high, while the intensity of coagulation is mainly affected by the number concentration. Both nucleation and coagulation result in the variation of average diameter of nanoparticles.

Fabrication and Studying the Mechanical Properties of A356 Alloy Reinforced with Al₂O₃-10% Vol. ZrO₂Nano-particles through Stir Casting

Al2O3-ZrO2 with a high level of hardness and toughness is known as ceramic steel. Due to its unique properties it can be used as a reinforcement in fabrication of metal matrix composites. In this study, nanoparticles of Al2O3-10% ZrO2 with an average size of 80 nm were used to fabricate Al matrix composites containing 0.5, 1, 1.5 and 2 wt.% of the reinforcement. The fabrication route was stir casting at 850?C. There is no report about usage of this reinforcement in fabrication of composites in the literature. The microstructures of the as-cast composites were studied by scanning electron microscope (SEM). Density measurement, hardness and tensile properties were carried out to identify the mechanical properties of the composites. The results revealed that with increasing the reinforcement content, density decreased while yield, ultimate tensile strength and compressive strength increased. Also, hardness increased by increasing the reinforcement content up to 1 wt.% Al2O3-10% ZrO2 but it decreased in the samples containing higher amounts of reinforcement.

Morphology Control over the Organic Nanoparticles of 1,3-Diphenyl-5-(9-anthryl)-2-pyrazoline

The organic nanoparticles of a blue-light-emitting molecule,1,3-diphenyl-5-(9-anthryl)-2-pyrazoline,were prepared by reprecipitation method using acetonitrile as the solvent for the molecular precursor. Three morphologies,spherical,doughnut-shaped and cubic,could be observed on the silicon substrate for the nanoparticles by the volume-controlled addition of acetonitrile. The evolution of particle morphology as a function of acetonitrile addition was attributed to the variation of the growth habits of the particles in the different environment. The nanoparticles exhibit the novel photoluminescence spectra as compared to those of monomer and the bulk crystals.

FePt纳米珊瑚的湿化学制备及生长过程

利用乙酰丙酮铁(Fe(acac)3)和乙酰丙酮铂(Pt(acac)2)为前驱物质,油胺(Oleylamine)做表面活性剂,通过湿化学法制备了珊瑚状FePt粒子(纳米珊瑚).透射电镜(TEM)分析表明:FePt纳米粒子形貌类似珊瑚,由短棒、球粒子交叉连接在一起;粒子具有良好的分散性,尺寸均匀,是化学无序的FCC结构.借助高分辨透射电镜(HRTEM)研究,推测其生长机制为:在反应初始阶段,前驱物质被还原,形成球形的Fe Pt晶核,晶核长大成均匀的单分散球形纳米粒子;随后在表面活性剂的作用下,当粒子界面晶格取向一致时,球形粒子自组装排列到一起,并"焊接"生长成各向异性的短棒状;随着反应继续进行,球形粒子或短棒持续交叉连接、生长,最终形成FePt纳米珊瑚.

Investigation on composite Au/TiO_2 nanoparticles (Ⅰ)——Synthesis and characterization

Nanometer sized Au/TiO\-2 particles were synthesized by irradiation of a HAuCl\-4 solution containing colloidal TiO\-2 with light of wavelength (λ)>330 nm. The absorption maximum attributed to the surface plasmon band of gold was observed at 540 nm, a red shift of about 20 nm from the position in aqueous solution. The Au clusters are situated on the surface of TiO\-2 in terms of microcrystallite, which was confirmed by HRTEM, EDS and XRD. The electronic interfaction between the metal and the suport was discussed.

简易方法合成具有类过氧化物酶活性的聚乙烯亚胺包覆的四氧化三铁用于高灵敏检测干扰素α-2b

在病毒感染和癌症治疗中,干扰素α-2b(IFN-α2b)的灵敏检测至关重要,因此需要开发经济、稳定的灵敏检测IFN-α2b的方法.传统的酶联免疫吸附测定(ELISA)中使用的天然酶存在制备成本高和稳定性差等问题.为了提高其灵敏度并降低成本,我们合成了聚乙烯亚胺(PEI)修饰的四氧化三铁磁性纳米粒子(Fe_(3)O_(4)@PEI MNPs).在基于ELISA的IFN-α2b检测中,这些磁性纳米粒子作为辣根过氧化物酶的替代品,提供了比色谱和传统ELISA技术更高的灵敏度,并且能够实现IFN-α2b的可视化检测.该免疫分析方法的线性范围为0.075-25 ng mL^(-1),检测限为0.055 ng mL^(-1).基于Fe_(3)O_(4)@PEI MNPs优异的过氧化物酶活性,该方法在用于检测IFN-α2b和其他蛋白质生物标志物监测方面具有临床应用潜力.

Self-assembled supramolecular immunomagnetic nanoparticles throughπ-πstacking strategy for the enrichment of circulating tumor cells

Owing to their high-specific binding toward targets as well as fast and convenient separation operations,immunomagnetic beads(IMBs)are widely used in the capture and detection of circulating tumor cells(CTCs).To construct the IMBs,surface modifications are generally performed to functionalize the magnetic cores(e.g.Fe_(3)O_(4)nanoparticles),and the employed surface modification strategies normally influence the structure and functions of the prepared IMBs in return.Different from the existing work,we proposed the use of supramolecular layer-by-layer(LBL)self-assembly strategy to construct the IMBs.In general,owing to theπ-πstacking interactions,the polydopamine,graphene oxide and‘molecular glue’γ-oxo-1-pyrenebutyric acid were self-assembled on Fe_(3)O_(4)nanoparticles sequentially,thereby accomplishing the integration of different functional components onto magnetic cores to prepare the self-assembled supramolecular immunomagnetic beads(ASIMBs).The ASIMBs showed high sensitivity,specificity and good biocompatibility to the model CTCs and low nonspecific adsorption to the negative cells(∼93%for MCF-7 cells and 17%for Jurkat cells).Meanwhile,ASIMBs possessed a remarkable potential to screen the rare MCF-7 cells out of large amounts of interfering Jurkat cells with the capture efficiency of 75-100%or out of mouse whole blood with the capture efficiency of 20-90%.The captured cells can be further recultured directly without any more treatment,which showed huge applicability of the ASIMBs for in vitro detection in clinical practices.

Synthesis of 5-[(2-hydroxynaphthalen-1-yl)diazenyl]isophthalic acid and its application to electrocatalytic oxidation and determination of adrenaline,paracetamol,and tryptophan

In this study,Au nanoparticles/poly 5-[（2-hydroxynaphthalen-l-yl）diazenyl]isophthalic acid film modified glassy carbon electrode（AuNPs/poly（NDI）/GCE） has shown excellent electrocatalytic activity toward the oxidation of adrenaline（ADR）,paracetamol（PAC）,and tryptophan（Trp）.The bare glassy carbon electrode（GCE） fails to separate the oxidation peak potentials of these molecules,while the poly（NDI） film modified electrode can resolve them.Electrochemical impedance spectroscopy（EIS）indicates that the charge transfer resistance of the bare electrode decreases as 5-[（2-hydroxynaphthalen-l-yl）diazenyl]isophthalic acid is electropolymerized on the bare electrode.Furthermore,EIS exhibits enhancement of electron transfer kinetics between analytes and the electrode after electrodeposition of Au nanoparticles.Differential pulse voltammetry results show that the electrocatalytic current increases linearly in the ranges of 0.01-680.0 μmol L^-1 for ADR,0.05-498.0 μmol L^-1 for PAC,and 3.0-632.0 μmol L^-1 for Trp;with detection limits（S/N = 3） of 0.009 μmol L^-1,0.005 μmol L^-1,and 0.09 μmol L^-1 for ADR,PAC,and Trp,respectively.The proposed method has been successfully applied for simultaneous determination of ADR,PAC,and Trp in biological samples.

CircZFR promotes colorectal cancer progression via stabilizing BCLAF1 and regulating the miR-3127-5p/RTKN2 axis

Aberrant expression of circular RNAs(circ RNAs)is frequently linked to colorectal cancer(CRC).Here,we identified circ ZFR as a promising biomarker for CRC diagnosis and prognosis.Circ ZFR was upregulated in CRC tissues and serum exosomes and its level was linked to cancer incidence,advanced-stages,and metastasis.In both in vitro and in vivo settings,circ ZFR promoted the growth and spread while suppressing apoptosis of CRC.Exosomes with circ ZFR overexpression promoted the proliferation and migration of cocultured CRC cells.Mechanistically,epithelial splicing regulatory protein 1(ESRP1)in CRC cells may enhance the production of circ ZFR.BCL2-associated transcription factor 1(BCLAF1)bound to circ ZFR,which prevented its ubiquitinated degradation.Additionally,circ ZFR sponged mi R-3127-5p to boost rhotekin 2(RTKN2)expression.Our TCP1-CD-QDs nanocarrier was able to carry and deliver circ ZFR si RNA(si-circ ZFR)to the vasculature of CRC tissues and cells,which inhibited the growth of tumors in patient-derived xenograft(PDX)models.Taken together,our results show that circ ZFR is an oncogenic circ RNA,which promotes the development and spread of CRC in a BCLAF1 and mi R-3127-5p-dependent manner.Circ ZFR is a possible serum biopsy marker for the diagnosis and a desirable target for further treatment of CRC.

纳米银的抗菌特性及对多重耐药菌株的抗菌作用

【目的】利用革兰氏阴性细菌、革兰氏阳性细菌和真菌的模式菌株分析纳米银的抗菌特性,并评价纳米银对多重耐药菌株的抗菌作用。【方法】利用生物法合成的纳米银,以微量肉汤法测定3种标准菌株的最小抑菌浓度(MIC)和最小杀菌浓度(MBC),并计算MBC/MIC比值。用系列浓度的纳米银处理3株标准菌株后经平板计数法绘制时间-杀菌曲线。采用菌落平板计数法测定了纳米银对3种标准菌株的"抗生素后效应"(post-antibiotic effect,PAE),最后在生物安全II级实验室测定纳米银对临床分离的多重耐药菌株的抗菌作用。【结果】用生物法合成了粒径5–30 nm的纳米银,zeta电位为–19.5 m V。该纳米银制剂对3种标准菌株的时间-杀菌曲线均表现为时间依赖型抗菌作用。纳米银对大肠杆菌和白色念珠菌"抗生素后效应"随着浓度增加而增加,对金黄色葡萄球菌无明显"抗生素后效应"。纳米银对3种标准菌株的MIC值和MBC值均在1.00–4.00μg/m L之间;对3株人源性多重耐药菌MIC值在6.00–26.00μg/m L之间,MBC值在1.00–32.00μg/m L之间;对14株动物源性多重耐药菌MIC值在4.00–10.00μg/m L之间,MBC值在8.00–16.00μg/m L之间。纳米银对所有测试菌株的MBC/MIC值均小于2。【结论】纳米银是一种时间依赖型的抗菌剂,有不同程度的"抗生素后效应",对人源和动物源性多重耐药菌有杀菌作用。

斜阳岛珊瑚礁区海泥可培养细菌的分离鉴定及其ECP抑菌作用

为探究斜阳岛珊瑚礁区海洋微生物的代谢产物活性,为天然材料制备新药物资源的开发提供一定的理论依据和实践指导,本研究从斜阳岛珊瑚礁区海泥分离纯化得到3株菌株,经鉴定分别为蜡状芽孢杆菌(Bacillus cereus)、Sphingopyxis terrae和Fictibacillus phosphorivorans,分别培养并提取3株细菌的胞外产物(extracellular products,ECP),与硝酸银制备成生物纳米银,OD法测定其抑菌(溶藻弧菌)动力曲线,用2倍稀释法测出3株菌的最小抑菌浓度(MIC)和最小杀菌浓度(MBC)分别是21.2μg/mL、18.8μg/mL、20.0μg/mL,用牛津杯法分别测定了3株菌与溶藻弧菌的抑菌活性,抑菌直径分别是(12.20±0.18)mm、(1.32±0.12)mm、(10.81±0.15)mm,安全性实验表明此3株菌对鱼体是安全的。本实验对斜阳岛珊瑚礁区海泥中可培养细菌进行了初步分离与鉴定,并利用分离菌的胞外产物合成生物纳米银,结果显示其具有一定的抑菌效果,从而证明其具有开发新的天然防腐剂和新药的潜力。

Mathematical modeling of nanodispersed hardening of FCC materials

The plastic deformation of the pipe made of Cu-based alloy hardened by incoherent nanoparticles and subjected to theuniform internal pressure was investigated. The limits of elastic and plastic resistance are determined. The insignificantexcess in the limit of the elastic resistance enables the plastic deformation in the most part of the pipe wall. The densities ofshear-forming dislocations and prismatic dislocation loops are higher in alloys strengthened with coarse particles than inalloys strengthened with fine particles. At small distances between the strengthening particles, this effect is the mostpronounced.