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Elaeocarpus hygrophilus Kurz. is a tropical tree that has recently been used for food and medicinal purposes. This study aimed to reveal the phytochemicals and evaluate the anti-influenza viral and neuroprotective effects of different parts of this plant including leaves, stems, fruit peels, and seeds. The study results indicated that the leaf extract was a potential candidate in the inhibition of the influenza viral replication through anti-neuraminidase receptors and attenuation of the glutamate-induced neuronal cell death and cellular oxidative stress. Using molecular networking as well as fragmentation, twenty-six known compounds were dereplicated from the leaves of E. hygrophilus. Molecular docking simulations of target proteins (PDB: 3CL0 and 4CXT) with these predicted compounds indicated that phenolic compounds from the EtOH leaf extract may be considered as active components for treating not only neuraminidase inhibitor-resistant strains but also activating Keap1/Nrf2 pathway. The anti-influenza viral and neuroprotective effects of the leaf extract and the link between the two activities could significantly contribute to the development of natural product drugs for influenza treatment and prevention of neuropsychiatric adverse events. These results suggested further research about the phytochemicals and the bio-guided isolation of the most active fractions from the leaf extract and their respective herbal drug formulations, with effective and secure aspects, to low-income populations of the tropics.

With the advent of senolytic agents capable of selectively removing senescent cells in old tissues, the perception of age-associated diseases has been changing from being an inevitable to a preventable phenomenon of human life. In the search for materials with senolytic activity from natural products, six new flavonostilbenes (1-6), three new phenylethylchromanones (7-9), three new phenylethylchromones (10-12), and four known compounds (13-16) were isolated from the roots of Rhamnoneuron balansae. The chemical structures of these isolated compounds were determined based on the interpretation of spectroscopic data, including 1D and 2D NMR, ECD, and HRMS. The absolute configuration of compound 1 was also determined by a Mosher ester analysis and ECD calculations. Compounds 6-8 were shown to selectively destroy senescent cells, and the promoter activity of p16INK4A, a representative senescence marker, was reduced significantly by compound 6. The present results suggest the potential activity of flavonostilbene and phenylethylchromanone skeletons from R. balansae as new senolytics.

The therapeutic efficacy of current cancer vaccines is far from optimal, mainly because of insufficient induction of antigen-specific T cells and because tumor cells can hijack immunosuppressive mechanisms to evade the immune responses. Generating specific, robust, and long-term immune responses against cancer cells and the attenuating of immunosuppressive factors are critical for effective cancer vaccination. Recently, the engineering of exosomes specifically bind to T cells, and then stimulating tumor-specific T-cell immune responses has emerged as a potential alternative strategy for cancer vaccination. In this study, we generated a bifunctional exosome combining the strategy of vaccination and checkpoint blockade. Exosomes prepared from Ovalbumin (OVA)-pulsed, activated dendritic cells were modified with anti-CTLA-4 antibody (EXO-OVA-mAb) to block this inhibitory molecule and to enhance the specificity of the exosomes toward T cells. Our study provides a unique strategy for functionalizing exosome membrane with anti-CTLA-4 antibody via lipid-anchoring method to synergize efficacy of cancer vaccination and immune checkpoint blockade against the tumor. Statement of Significance We designed T-cell-targeting exosomes (EXO-OVA-mAb) decorated with costimulatory molecules, MHCs, antigenic OVA peptide, and anti-CTLA-4 antibody, combining the strategies of vaccines and checkpoint blockade. The exosomes showed enhanced binding to T cells in tumor-draining lymph nodes, effectively induced T-cell activation, and improved the tumor homing of effector T cells, ultimately significantly restraining tumor growth. Thus, EXO-OVA-mAb greatly facilitates T-cell targeting, induces a strong tumor-specific T-cell response, and increased the ratio of effector T cells/regulatory T cells within tumors, resulting in appreciable tumor growth inhibition.

During an effort to find insulin mimetic compounds, the leaves of Gymnema inodorum were shown to have a stimulatory effect on glucose uptake in 3T3-L1 adipocyte cells. Bioassay-guided fractionation on a 70% ethanol extract of G. inodorum was applied to yield two new (1 and 2) and two known (8 and 9) oleanane triterpenoids with a methyl anthranilate moiety together with five further new oleanane triterpenoids (3-7). The chemical structures of all isolates were determined based on their spectroscopic data, including IR, UV, NMR, and mass spectrometric analysis. The isolated compounds (1-9) were determined for their stimulatory activities on glucose uptake in differentiated 3T3-L1 adipocyte cells using 2-deoxy-2-[(7-nitro-2,1,3-benzoxadiazol-4-yl)amino]-d-glucose (2-NBDG) as a fluorescent-tagged glucose probe. Three compounds (3, 5, and 9) showed stimulatory effects on the uptake of 2-NBDG in 3T3-L1 adipocyte cells. Chemicals with a methyl anthranilate moiety have been considered as crucial contributors of flavor odor in foods, and quantitative analysis showed the content of compound 8 to be 0.90 ± 0.01 mg/g of the total extract. These results suggest that the leaves of G. inodorum have the potential to be used as an antidiabetic functional food or tea.

The major class of bioactive metabolites in Gymnema sylvestre, a popular Ayurvedic medicinal plant for the treatment of diabetes mellitus, is oleanane triterpenoids. In this study, a targeted, biosynthesis-inspired approach using UHPLC-qTOF/MS was implemented to elucidate the whole chemical profile of this plant for the standardization of the Vietnamese G. sylvestre variety. The known compounds were first determined to identify the building blocks of the biosynthetic intermediates and the construction rules for synthesizing oleanane triterpenoids in the plant. These blocks were recombined to build a virtual library of all reasonable compounds consistent with the deduced construction rules. Various techniques, including relative mass defect filtering, multiple key ion analysis, mass fragmentation analysis, and comparison with standard references, were applied to determine the presence of these predicted compounds. Conventional isolation and structure elucidation of six of the new compounds were carried out to identify the new building blocks and validate the assignments. Consequently, 119 peaks were quickly assigned to oleanane triterpenoids, and among them, 77 peaks were predicted to be new compounds based on their molecular formulas and mass fragmentation patterns. All the identified metabolites were then classified into different layers to analyze their logical relationships, and a multilayered chemical profile of the oleanane triterpenoids was constructed. This new approach is expected to be practical for characterizing structures of modular secondary metabolites, such as triterpenoid saponins, and for proposing biosynthetic relationships among compounds of the same class of metabolites in medicinal plants.

Melicope pteleifolia has long been consumed as a popular vegetable and tea in Southeast Asian countries, including Malaysia and southern mainland China, and is effective in the treatment of colds and inflammation. In the search for active metabolites that can explain its traditional use as an antipyretic, six new phloroacetophenone derivatives (3-8) along with seven known compounds (1, 2, and 9-13) were isolated from the leaves of M. pteleifolia. Their chemical structures were confirmed by extensive spectroscopic analysis including NMR, IR, ECD, and HRMS. All compounds isolated from the leaves of M. pteleifolia (1-13) have a phloroacetophenone skeleton. Notably, the new compound 8 contains an additional cyclobutane moiety in its structure. The bioactivities of the isolated compounds were evaluated, and compounds 1, 6, and 7 inhibited tumor necrosis factor-α-induced prostaglandin E2. Moreover, the major constituent, 3,5-di-C-β-d-glucopyranosyl phloroacetophenone (1), was found to be responsible for the antipyretic activity of M. pteleifolia based on in vivo experiments.

As part of an ongoing study of new insulin mimetic agents from medicinal plants, the 70% EtOH extract of Symplocos cochinchinensis was found to have a stimulatory effect on glucose uptake in 3T3-L1 adipocyte cells. The intensive targeted isolation of this active extract resulted in ten new hydroxyoleoside-type compounds conjugated with a phenolic acid and monoterpene (1–6 and 8–11), as well as four known compounds (7 and 12–14). The chemical structures of the new compounds were determined based on spectroscopic data analysis (1H and 13C NMR, HSQC, HMBC, NOESY and MS). The absolute configurations of the isolated compounds were determined by electronic circular dichroism (ECD) analysis of derivatives obtained after a series of reactions, such as those with dirhodium (ІІ) tetrakis (trifluoroacetate) and dimolybdenum (ІІ) tetraacetate. In vitro, compounds 3, 7 and 8 moderately increased the 2-deoxy-2-[(7-nitro-2,1,3-benzoxadiazol-4-yl)amino]-D-glucose (2-NBDG) uptake level in differentiated 3T3-L1 adipocytes. For further studies, we evaluated their effects on the expression of glucose transporter-4 (GLUT4), its translocation, protein tyrosine phosphatase 1B (PTP1B) inhibition and expression of phosphorylated Akt. Our results strongly suggest that the traditional uses of this plant can be described as active constituents by hydroxyoleoside-type compounds.

A library of extracted natural materials (Korea Bioactive Natural Material Bank) have been screened to discover candidates for the treatment of non-alcoholic liver disease (NAFLD), and the 70% ethanol extract of Sicyos angulatus was found to inhibit hepatic lipid accumulation. Bioassay–guided fractionation of this bioactive extract yielded five previously undescribed flavonoid glycosides and one previously undescribed flavonolignan glycoside along with seven known flavonoid glycosides. The chemical structures of these compounds were elucidated by a combination of extensive spectroscopic analysis, including MS, NMR and UV techniques. Eight compounds of all isolated compounds showed inhibitory effects on the lipid accumulation induced by high concentrations of palmitic acid and glucose in HepG2 cells. Four selected compounds were tested for lipid content in a dose-dependent manner (10, 20 and 40 μM), and among those compounds, kaempferol 3-O-β- d -glucopyranosyl-7-O-α- l -rhamnopyranoside showed the strongest inhibition of hepatic lipid production in HepG2 cells. In an oil-red O staining assay, five compounds were shown to reduce hepatic lipid accumulation better than what was observed in the vehicle control group. The present study suggests a new class of chemical entities for developing bioactive agents for the treatment of diseases caused by fat accumulation in the liver.

In this study, nanocrystalline ZnNdxFe2−xO4 ferrites with x = 0.0, 0.01, 0.03 and 0.05 were fabricated and used as a catalyst for dye removal potential. The effect of Nd3+ ions substitution on the structural, optical and photo-Fenton activity of ZnNdxFe2−xO4 has been investigated. The addition of Nd3+ ions caused a decrease in the grain size of ferrites, the reduction of the optical bandgap energies and thus could be well exploited for the catalytic study. The photocatalytic activity of the ferrite samples was evaluated by the degradation of Rhodamine B (RhB) in the presence of H2O2 under visible light radiation. The results indicated that the ZnNdxFe2−xO4 samples exhibited higher removal efficiencies than the pure ZnFe2O4 ferrites. The highest degradation efficiency was 98.00%, attained after 210 min using the ZnNd0.03Fe1.97O4 sample. The enhanced photocatalytic activity of the ZnFe2O4 doped with Nd3+ is explained due to the efficient separation mechanism of photoinduced electron and holes. The effect of various factors (H2O2 oxidant concentration and catalyst loading) on the degradation of RhB dye was clarified.

This research was conducted to evaluate the effect of $\alpha$-amylase and glucoamylase mixture at various hydrolysis time (0,4,6,8 and 12 hours) to morphological characteristics and physical properties of porous corn starch granules. Scanning Electron Microscopy (SEM) showed the number and size of holes on the surface of starch granules increased with hydrolysis time; moreover, starch granule structure was broken at 8 and 12 hours. The hydrolyzed level of starch granules was increased gradually with reaction time; the highest hydrolysis value was 63.534% in 12 hours of reaction. The results indicated that porous starch had higher adsorption capacity than native starch which was showed in higher oil and water holding ability. Additionally, swelling and solubility of porous corn starch were increased with the prolonging of hydrolysis time and higher than that of native starch samples. Color value tended to increase with increasing hydrolysis time; however, the difference was very small. The results also indicated that viscosity and transmittance of the hydrolyzed starch sample decreased as the hydrolysis time increased as well as lower than native starch. Thus, porous corn starch could be a potential ingredient in the food field.

Senescent cells drive atherosclerosis at all stages and contribute to cardiovascular disease. However, the markers in these senescent aortic plaques have not been well studied, creating a huge obstacle in the exploration of a precise and efficient system for atherosclerosis treatment. Recently, CD9 has been found to induce cellular senescence and aggravated atherosclerotic plaque formation in apolipoprotein E knockout (ApoE-/-) mice. In the present study, this result has been leveraged to develop CD9 antibody-modified, hyaluronic acid-coated mesoporous silica nanoparticles with a hyaluronidase-responsive drug release profile. In invitro models of senescent foamy macrophages and senescent endothelial cells stimulated with oxidized high-density-lipoprotein, the CD9 antibody-modified mesoporous silica nanoparticles exhibit high cellular uptake; reduce the reactive oxygen species level, high-density lipoprotein oxidation, and production of TNF-α and IL-6; and attenuate the senescence process, contributing to improved cell viability. In vivo experiment demonstrated that these nanoparticles can successfully target the senescent lesion areas, deliver the anti-senescence drug rosuvastatin to the senescent atherosclerotic plaques (mainly endothelial cells and macrophages), and alleviate the progression of atherosclerosis in ApoE-/- mice. By providing deep insight regarding the markers in senescent atherosclerotic plaque and developing a nano-system targeting this lesion area, the study proposes a novel and an accurate therapeutic approach for mitigating atherosclerosis through senescent cell clearance.

Gymnema sylvestre (Retz.) R. Br. ex Schult. has a long history to be used as an antidiabetic herbal medicine. Various varieties of G. sylvestre, have been studied intensively on their 3β-hydroxy oleanane triterpenoid composition for hypoglycemic effects. It is also well-known that most species belonging to the same genus have similar chemical composition and biological activity. Thus, an extract of the Gymnema latifolium Wall. ex Wight, which showed considerable protein tyrosine phosphatase 1B (PTP1B) inhibitory activity (>70% inhibition at 30 μg/mL), was studied intensively. Extensive chemical investigation on the 70% EtOH of G. latifolium led to the isolation of four previously undescribed oleanane hemiacetal glycosides, gymlatinosides GL1-GL4, three previously undescribed oleanane glycosides, gymlatinosides GL5-GL7, and two known 3β-hydroxy oleanane analogs. The structures of the previously undescribed compounds were elucidated using diverse spectroscopic methods. The hemiacetal structure of the glycoside portion was further elaborated precisely by HMBC and J resolved proton NMR. Gymlatinosides GL2 and GL3 showed considerable PTP1B inhibitory effect.

As part of ongoing research to find new antidiabetic agents from medicinal plants, the chemical composition of Gynostemma longipes, an ethnomedicinal plant used to treat type 2 diabetes mellitus by local communities in Vietnam, was investigated. Ten new dammarane triterpenes, including two 3,4- seco-dammarane analogues, secolongipegenins S1 and S2 (1 and 2), a 3,4- seco-hexanordammarane, secolongipegenin S3 (3), two hexanordammarane glycosides, longipenosides ND1 and ND2 (4 and 5), and five other dammarane glycosides, longipenosides GL1-GL5 (6-10), were isolated from a 70% EtOH extract of the whole G. longipes plant. The structures of the new compounds were elucidated using diverse spectroscopic methods. All of the isolates were evaluated for their stimulatory activities on glucose uptake in differentiated 3T3-L1 adipocyte cells using 2-[ N-(7-nitrobenz-2-oxa-1,3-diazol-4-yl)amino]-2-deoxy-d-glucose as a fluorescent-tagged glucose probe. The stimulant activities on glucose uptake by the test compounds were mediated via the activation of the AMPK pathway using differentiated mouse C2C12 skeletal myoblasts. Consequently, compounds 1, 2, and 4 enhanced glucose uptake and GLUT4 translocation significantly by regulating the AMPK signaling pathway.

During an attempt to discover insulin mimetics, thirteen new triterpenoid saponins (1–13), including three phytolaccagenic acids (1, 2, and 12) and ten serjanic acids (3–11 and 13), as aglycones were isolated from a 70% ethanol extract of leaves and stems from Pericampylus glaucus. The chemical structures of compounds 1–13 were determined through spectroscopic data analysis, including NMR, IR, and HRESIMS. All isolated compounds (1–13) were evaluated using 2-deoxy-2-[(7-nitro-2,1,3-benzoxadiazol-4-yl)amino]- d -glucose (2-NBDG) as a fluorescent-tagged glucose probe to determine their stimulatory effects on glucose uptake in differentiated 3 T3-L1 adipocyte cells. Consequently, four compounds (4, 7, 11, and 12) exhibited stimulatory effects on glucose uptake.

In this study, dual drug-loaded nanoparticles were constructed to co-deliver low-dose doxorubicin (DOX) and miR-200c (DOX/miR-NPs) to inhibit programmed death-1 receptor (PD-L1) expression and trigger immunogenic cell death (ICD) in cancer cells. Two block copolymers, folic acid (FA)-conjugated PLGA-PEG (PLGA-PEG-FA) and PLGA-PEI, were formulated as folate-targeted NPs and loaded with DOX and miR-200c. The NPs, which were formed as nanosize objects (110.4 ± 2.1) with narrow size distribution (0.19 ± 0.02), effectively protected the miR-200c from degradation in serum. Modifying the NPs with FA increased not only their uptake by cancer cells in vitro but also their accumulation in tumor microenvironments in vivo, as compared with those properties of non-FA-modified NPs. The DOX/miR-NPs also exhibited efficacious inhibition of PD-L1 expression and robust induction of ICD in cancer cells in vitro and in vivo, resulting in increased dendritic cell maturation and CD8+ T cell response towards cancer cells. Furthermore, tumor growth was significantly inhibited by folate-targeted NPs loaded with the low-dose DOX/miR-200c combination, but not by treatments with free DOX, miR-NPs or DOX-NPs. Thus, our results suggest that simultaneous PD-L1 inhibition via microRNAs and the induction of an immunogenic tumor microenvironment via low-dose cytotoxic drugs may improve cancer therapy efficacy.

The aging population is growing rapidly around the world and there is also an increase in sarcopenia, which is characterized by decreased muscle mass, strength and function in the elderly population. AMP-activated protein kinase (AMPK) is an essential sensor and regulator of glucose, lipid and energy metabolism throughout the body. Previous studies have shown that AMPK pathway activation by regular exercise and appropriate dietary control have beneficial effects on skeletal muscle. In the process of searching for new AMPK activators from medicinal plants, we isolated and characterized eight new 12,23-dione dammarane triterpenoids (1–3 and 5–9), as well as one known gypentonoside A from Gynostemma longipes. When all isolates were tested for their AMPK activation activities, seven compounds (1 and 3–8) were significantly activated AMPK phosphorylation in mouse C2C12 skeletal muscle cell lines. Since G. longipes contained a significant amount of active compound 1 (over 2.08% per dried raw plant), it suggested the potential of this plant to be developed as a functional food or botanical drug that enhances muscle proliferation by activating AMPK signaling pathways.

Oligostilbenes are polyphenol oligomers derived from resveratrol and are commonly produced by members of the Gnetaceae family, and many researchers have focused on their anti-inflammatory activities. The EtOAc fraction of a Gnetum latifolium extract showed inhibitory activity against neuroinflammation induced by the transfection of Aβ1-42 into microglial BV-2 cells. The bioassay-guided isolation of the 70% EtOH extract of this plant resulted in three previously undescribed resveratrol oligostilbenes and ten known stilbene derivatives. The structures of the isolated compounds were established based on extensive NMR spectroscopic analysis. The absolute configurations of the three undescribed compounds were confirmed by comparison with available compounds with known stereochemistry and by ECD calculations and molecular modelling. Latifoliols A and B are the first reported oligostilbenes with a bridged 3-oxabicyclo[3.3.0]octane moiety, and latifoliol C was formed by the condensation of gnemontanin G with oxyresveratrol. Moreover, the hypothetical biogenetic pathway of latifoliols A, B and C was proposed. The potential anti-inflammatory activities of the thirteen isolated compounds were tested by measuring their effect on the secreted NO concentrations induced by transfection with plasmids expressing the Aβ1-42 gene in the BV-2 cell line. Interestingly, cis- and trans-shegansu B and latifolol, whose structures contained double bonds, strongly inhibited NO secretion in BV-2 cells, supporting the double binding effect of the stilbene derivative on inhibitory activity.

International audience; Three different liquid interfaces, water/air, thiophene/air, and water/thiophene, were probed using the second harmonic generation (SHG) technique. Thiophene and water have been chosen because the hyperpolarizability of these molecules has already been measured or calculated and the different values can be found in literature. We have studied the microscopic structure of these interfaces by comparing the components of the second order susceptibility tensor determined from the SHG polarization curve analysis with those determined via a molecular dynamics (MD) simulation of these interfaces. We have indeed computed the structure and orientation of water and thiophene molecules at the liquid/air and liquid/liquid (L/L) interfaces as a function of the distance from the interface. The integrated susceptibility values calculated by MD simulations agree well with SHG results and validate the choice of force fields that should permit to quantify more complex L/L interfaces.

Ecklonia cava is edible seaweed that is found in Asian countries, such as Japan and Korea, and, its major components include fucoidan and phlorotannins. Phlorotannins that are isolated from E. cava are well-known to have an antioxidant effect and strong antiviral activity against porcine epidemic diarrhea virus (PEDV), which has a high mortality rate in piglets. In this study, the bioactive components were determined based on two different approaches: (i) bio-guided isolation using the antiviral activity against the H1N1 viral strain, which is a representative influenza virus that originates from swine and (ii) high-resolution mass spectrometry-based dereplication, including relative mass defects (RMDs) and HPLC-qTOFMS fragmentation analysis. The EC70 fraction showed the strongest antiviral activity and contained thirteen phlorotannins, which were predicted by dereplication. Ten compounds were directly isolated from E. cava extract and then identified. Moreover, the dereplication method allowed for the discovery of two new phlorotannins. The structures of these two isolated compounds were elucidated using NMR techniques and HPLC-qTOFMS fragmentation analysis. In addition, molecular modelling was applied to determine the absolute configurations of the two new compounds. The antiviral activities of seven major phlorotannins in active fraction were evaluated against two influenza A viral strains (H1N1 and H9N2). Six of the compounds showed moderate to strong effects on both of the viruses and phlorofucofuroeckol A (12), which showed an EC50 value of 13.48 &plusmn, 1.93 &mu, M, is a potential active antiviral component of E. cava.

Bone tissue is characterized by nanopores inside the collagen-apatite matrix where fluid can exist and flow. The description of the fluid flow within the bone has however mostly relied on a macroscopic continuum mechanical treatment of the system, and, for this reason, the role of these nanopores has been largely overlooked. However, neglecting the nanoscopic behaviour of fluid within the bone volume could result in large errors in the overall description of the dynamics of fluid. In this work, we have investigated the nanoscopic origin of fluid motion by conducting atomistic molecular dynamics simulations of water confined between two parallel surfaces of hydroxyapatite (HAP), which is the main mineral phase of mammalian bone. The polarizable core–shell interatomic potential model used in this work to simulate the HAP–water system has been extensively assessed with respect to ab initio calculations and experimental data. The structural (pair distribution functions), dynamical (self-diffusion coefficients) and transport (shear viscosity coefficients) properties of confined water have been computed as a function of the size of the nanopore and the temperature of the system. Analysis of the results shows that the dynamical and transport properties of water are significantly affected by the confinement, which is explained in terms of the layering of water on the surface of HAP as a consequence of the molecular interactions between the water molecules and the calcium and phosphate ions at the surface. Using molecular dynamics simulations, we have also computed the slip length of water on the surface of HAP, the value of which has never been reported before.

Tuan Hiep Tran,1 Thiruganesh Ramasamy,1 Ju Yeon Choi,1 Hanh Thuy Nguyen,1 Thanh Tung Pham,1 Jee-Heon Jeong,1 Sae Kwang Ku,2 Han-Gon Choi,3 Chul Soon Yong,1 Jong Oh Kim11College of Pharmacy, Yeungnam University, Dae-Dong, 2College of Korean Medicine, Daegu Haany University, Gyeongsan, 3College of Pharmacy, Hanyang University, Hanyangdaehak-ro, Sangnok-gu, Ansan,South KoreaAbstract: The attachment of polyethylene glycol (PEG) increases the circulation time of drug-containing nanoparticles; however, this also negatively affects cellular uptake. To overcome this problem, unique lipid polymer hybrid (LPH) nanoparticles were developed with a pH-responsive PEG layer that detached prior to cell uptake. Docetaxel (DTX) was incorporated into the lipid core of the nanoparticles, which was then shielded with the pH-responsive block co-polymer polyethylene glycol-b-polyaspartic acid (PEG-b-PAsp) using a modified emulsion method. The optimized LPH nanoparticles were ~200nm and had a narrow size distribution. Drug release from DTX-loaded LPH (DTX-LPH) nanoparticles was pH-sensitive, which is beneficial for tumor targeting. More importantly, DTX-LPH nanoparticles were able to effectively induce apoptosis in cancer cells. The negative surface charge and PEG shell of vehicle remarkably enhanced the blood circulation and physiological activity of DTX-LPH nanoparticles compared with that of free DTX. The nanoparticles were also found to reduce the size of tumors in tumor-bearing xenograft mice. The in vivo anticancer effect of DTX-LPH nanoparticles was further confirmed by the elevated levels of caspase-3 and poly ADP ribose polymerase found in the tumors after treatment. Thus, the results suggest that this novel LPH system could be an effective new treatment for cancer.Keywords: docetaxel, polyaspartic acid, drug delivery systems, antitumor, pH-sensitive

We describe the process of modification of the platinum (Pt) nanowire surface and subsequent immobilisation of enzyme glucose oxidase (GOx) on Pt nanowires (PtNWs) for direct glucose measurement. A cyclic voltammetry technique was used to measure electrochemical oxidation between GOx and glucose. PtNW arrays were first fabricated and then functionalised with cysteamine' which in turn acted as a chemical linkage for the enzyme conjugation. Afterward' the enzyme modified PtNWs arrays were subjected to the model test to check the effect of the process modification. The cyclic voltammograms of GOx immobilised Pt chips in PBS (1M' pH of 7) showed the most stable result. The enzymatic modified PtNW electrodes were then successfully determined glucose in diabetic blood samples with the concentrations from 125 μM to 16.5 mM' a deviation of ± 3%. The obtained results clearly indicate the potential of a next-generation of glucose sensor based on PtNW in application diabetic diagnosing. Refereed/Peer-reviewed

International audience; The tangential momentum accommodation coefficient (TMAC) of argon atoms on a Pt(111) surface has been investigated using a multi-scale computational approach in order to emphasize the effect of the Pt-Ar pairwise potential on this parameter. For the different Pt-Ar pairwise potentials available in the literature, the TMAC has been determined by Molecular Dynamics simulations from the difference of the incident and reflected velocities of projected Ar atoms on the atomistic Pt surface. Temperature and incident angle dependencies of this parameter are also explored. A new Pt-Ar potential has also been calculated using periodic density functional theory computations. The resulting potential successfully reproduced the available experimental data and is compared with the previous empirical potentials. The TMAC deduced from our pairwise potential is 0.42 at T = 300 K.

In this paper, we study the influence of platinum (100) surface morphology on the tangential-momentum accommodation coefficient with argon using a molecular dynamics method. The coefficient is computed directly by beaming Ar atoms onto the surfaces and measuring the relative momentum changes. The wall is maintained at a constant temperature and its interaction with the gas atoms is governed by the Kulginov potential. To capture correctly the surface effect of the walls and the atoms' trajectories, the quantum Sutton-Chen multibody potential is employed between the Pt atoms. The effects of wall surface morphology, incident direction, and temperature are considered in this work and provide full information on the gas-wall interaction.

Biosensors have been rapidly developed recently. Biological receptors, such as antibodies, must be immobilized on these sensors' surfaces to make the sensor capable of capturing a target analyte. In this research we studied how to modify a gold-coated surface of a microcantilever, a sensor with high potential in biological and medical applications. Thiol chemistry was adapted to create a cysteamine layer on a gold surface, and subsequently glutaraldehyde was used as a cross-linking agent to react with amine groups in receptors. In order to evaluate the efficiency of immobilizing protein on an Au surface and also whether the protein retains its biological activity, horseradish peroxidase enzyme (HRP) with its activity to catalyze a reaction between 2,2'-azino-bis [3-ethylbenzothiazoline-6-sulphonic acid] (ABTS) and was used as a testing protein. The result showed that HRP was immobilized successfully on cysteamine and glutaraldehyde layers and retained its activity. The cantilever's tip deflection was also measured, and results showed that each layer created surface stress and made the cantilever bend?in particular, the cysteamine layer induced bending as high as 6 ?m. An antibody of alpha-fetoprotein (AFP) was immobilized on the cantilever surface, and the measurement deflection showed that the sensor responded to solution containing AFP with concentration from 100 to 500 ng ml?1.

A silicon nanowire field-effect transistor based sensor (SiNW-FET) has been proved to be the most sensitive and powerful device for bio-detection applications. In this paper, SiNWs were first fabricated by using our recently developed deposition and etching under angle technique (DEA), then used to build up the complete SiNW device based biosensor. The fabricated SiNW biosensor was used to detect DNA of genetically modified maize. As the DNA of the genetically modified maize has particular DNA sequences of 35S promoter, we therefore designed 21 mer DNA oligonucleotides, which are used as a receptor to capture the transferred DNA of maize. In our work, the SiNW biosensor could detect DNA of genetically modified maize with concentrations down to about 200 pM.

In this paper, we report the results of the surface oxidation of platinum (Pt) microwires in aqueous sulfuric acid (H 2 SO 4) solutions by using a cyclic voltammetry technique. The Pt microwire chips were scanned and applied with voltage potentials ranging from 0 to 1.4 V in the H 2 SO 4 solution with concentrations from 0.0003 to 0.0018 M to find out the optimized concentration of sulfuric acid for the oxidation process. The cyclic voltammetry (CV) measurements show the oxidation peak at a potential range from 1.1 to 1.2 V. This is the peak of the interfacial place exchange of chemisorbed O (O chem ) and surface Pt atoms, resulting in the formation of a quasi-3D surface PtO lattice comprising Pt 2+ and O 2−. The oxidized surface Pt microwires were then functionalized with a 3-aminopropyl triethoxy silane (APTES) and glucose oxidase (GOD) was immobilized onto the functionalized chips for further application in glucose detection. By using this process, Pt microwires have been used for the successful detection of glucose in solution with concentrations in the range of 4–20 mM.

Electrochemical DNA (E-DNA) sensors, which are rapid, reagentless and readily integrated into microelectronics and microfluidics, appear a promising alternative to optical methods for the detection of specific nucleic acid sequences. In keeping with this, a large number of distinct E-DNA architectures have been reported to date. Most, however, suffer from one or more drawbacks, including low signal gain, signal-off behavior or instability. To remedy these problems, we report here the development of a signal-on E-DNA architecture that achieves both high signal gain and good stability. This new sensor employs a commercially synthesized, asymmetric hairpin DNA as its recognition and signaling probe, the shorter arm of which is labeled with a redox reporting methylene blue at its free end. Unlike all prior E-DNA architectures, in which the recognition probe is attached via a terminal functional group to its underlying electrode, the probe employed here is affixed using a thiol group located internally, in the turn region of the hairpin. Hybridization of a target DNA to the longer arm of the hairpin displaces the shorter arm, allowing the reporter to approach the electrode surface and transfer electrons. The observed signal gain is sufficient to achieve a demonstrated detection limit of 25 pM.

Among biosensors of various types, the silicon nanowire field–effect transistor (SiNW–FET) is believed to be the most sensitive and powerful device for bio–applications. In fact, these devices have demonstrated the ability to detect a variety of analyses such as particular DNA sequences, cancer biomarkers and larger entities such as viruses. The principle of sensing is based on the variation of conductivity resulting from a disturbance of charge on the surface of the SiNW–FET. In this study, we have used two different processes for surface modification of silicon nanowire. As the DNA of liver cancer cells has mutation at codon 249 which changes one base guanine (G) by base thymine (T), we thus designed 17–mer DNA oligonucleotides, which were used as a receptor to capture the DNA of p53 mutated gene. The fabricated SiNW biosensor could detect DNA of p53 mutated gene with concentrations down to about 100 pM.

In this paper we present an innovative method, deposition and etching under angles (DEA), for the fabrication of ready-for-measurement platinum (Pt) nanowires at the wafer-scale. The presented fabrication approach utilizes common techniques of conventional microfabrication technology, such as microlithography, thin-film deposition and wafer-scale ion beam etching, to realize an array of Pt nanowires on a silicon substrate with an insulation layer of silicon dioxide. Well-defined nanowire arrays with wire width down to 30 nm and wire length of up to several millimeters have been realized. Furthermore, each Pt nanowire from the array is individually electrically addressable, for multiplex detection. To prove the potential applications of the fabricated Pt nanowire chips, utilization of the fabricated Pt nanowire chip in glucose detection is presented and discussed.