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Photocatalytic membrane reactors (PMRs) have been widely used in wastewater treatment over the past few years. In this study, P-doped g-C3N4 (PCN), a metal-free, visible light (Vis)-driven photocatalyst, was prepared and coated on an Al2O3 substrate followed by integration with an inorganic Al2O3 hollow fiber membrane module for use as a PMR. The 10 wt % of PCN exhibited the highest degradation activity for methyl blue (MB) removal under Vis irradiation because the C sites and vacancies within the heptazine rings of the CN units were substituted with P to improve charge separation and reduce the number of unpaired electrons. The PMR exhibits higher efficiency and stability in the removal of MB, methyl orange, phenol solution, and a mixture of the three organic compounds than do individual hollow fiber membranes or photocatalysis systems. The TOC (total organic carbon) analysis revealed that more than 92% of the phenol was decomposed and mineralized in the PMR, which also had a MB removal efficiency of greater than 90% when repeatedly used for four times. These results indicate that the PMR developed in this study is highly active and stable, and can serve as a promising system for effective removal of organic pollutants in wastewater.

Omniphobic alumina hollow fiber membranes were developed for direct contact membrane distillation (DCMD) with a low surface tension feed in this study. Alumina hollow fiber (HF) membranes were prepared as the membrane substrates, and chemical bath deposition methods were applied to deposit ZnO nanorods and nanoparticles on the HF membranes. The SEM, EDX, and AFM analyses showed that the ZnO nanostructures were effectively deposited on the membrane surfaces and able to increase the surface roughness. After surface fluorination by FAS17, the HF membranes deposited by ZnO nanorods and nanoparticles demonstrated contact angles of 128.7° and 138.1° for a 90% v/v ethanol/water mixture, both of which were higher than 114.8° for the pristine HF membrane without ZnO nanostructures. In the DCMD experiments with the sequential addition of SDS from 0.2 to 2.0 mM, the HF membranes with ZnO nanostructures exhibited superior wetting resistances with low surface tension feeds compared to that of the pristine HF membranes. Moreover, the HF membranes with the deposited ZnO nanoparticles had the best wetting resistance, and the permeate water flux was maintained for 24 h using a 2.0 mM SDS (70 °C 1 M NaCl) solution as an initial feed. The results not only suggested that the deposition of nanostructures enhanced the wetting resistance of the alumina hollow fiber membranes to low surface tension liquids but also showed the promise of utilizing these membranes for the desalination of low surface tension wastewaters.

Water scarcity is one of the most serious global challenges of our time. One of the currently resolutions to this shortage is desalination. So far, most research on desalination has focused on preparing photothermal materials which possess the property of light-to-heat conversion. However, changing the intrinsic properties of water to improve the efficiency of solar evaporation has rarely been discussed. A new concept to increase the efficiency of desalination via destroying hydrogen bonds based on gold nanoparticles-adsorbed ceramic rods (AuNPs@CRs) is proposed here for the first time. Weakening the strength of interactions within water molecules by illumination with resonant light produces easily evaporable plasmon-activated water (PAW). This proposed system exhibits high efficiencies of steam generation in different experimental environments. Meanwhile, it was 140.0% and 107.5% more efficient than untreated water in an oven and an indoor environment, respectively. The source of resonant light from sunlight on a sunny or cloudy day can also achieve this performance. In addition, the results of water pump suction and direct contact membrane distillation (DCMD) further demonstrated that the illuminated AuNPs@CR system exhibits high potential for desalination.

Hydrophobic alumina hollow fiber membranes were first used for sucrose concentration in a vacuum membrane distillation (VMD) system. The alumina hollow fiber membranes were prepared using the combined phase inversion and sintering method and then grafted with FAS to impart hydrophobicity. The as-prepared hydrophobic alumina hollow fiber membrane had a high mechanical strength of 191 MPa, a high water contact angle of 140° and a high liquid entry pressure of water of 5.0 bar. Fifty-two hydrophobic alumina hollow fibers were packed into a shell-and-tube module. To evaluate the sucrose concentration performance of the prepared membrane module, the effects of various parameters on the permeate flux, such as the feed flow rate, temperature, vacuum pressure and concentration, were investigated in the VMD system. In the batch sucrose concentration tests, an 8 L 10°Brix sucrose solution was successfully concentrated to 50°Brix by removing 6.4 L of water using the VMD system. At a feed flow rate of 5 L/min and temperature of 70 °C, the permeate flux remained as high as 35.1 and 19.0 kg/m2 h when the sucrose solution was concentrated to 10°Brix and 50°Brix. Furthermore, the permeate flux could be recovered in a new concentration cycle after the membrane module was washed with pure water. The results revealed that the hydrophobic alumina hollow fiber membranes are promising and feasible for concentration processes in a VMD system.

An omniphobic membrane was fabricated for membrane distillation (MD) by effectively depositing ZnO nanoparticles on a hydrophilic glass fiber (GF) membrane using a chemical bath deposition method to create hierarchical re-entrant structures, followed by surface fluorination and the addition of a polymer coating to lower the surface energy of the membrane. The omniphobic membranes possessed a particulate membrane morphology and an extremely high fluorine concentration on the surface. The omniphobicity of the fabricated membrane was indicated by the contact angles for water and ethanol, which were as high as 152.8 ± 1.1° and 110.3 ± 1.9°, respectively. Compared to hydrophobic GF membranes without deposited ZnO nanoparticles, the omniphobic membrane revealed a higher wetting resistance to low surface tension feed solutions in direct membrane distillation (DCMD) experiments. The water flux was stably maintained in a 0.3 mM sodium dodecyl sulfate (SDS) solution (60 °C 1 M NaCl) with salt rejection rate higher than 99.99%. The results suggest that the omniphobic membrane exhibited not only superior wetting resistance to low surface tension liquids but also promise for desalinating low surface tension wastewaters.

A new simulation scheme was established for strategically constructing cross-linked organic-inorganic mixed matrix membrane materials. This is a multiscale method using customized programming to effectively model complicated nanostructures. The effects of hybrid fillers in the chitosan/graphene oxide composite membranes are systematically elucidated at the molecular scale. Observed from the radial distribution function analysis, the significant enhancement of the separation performance in the dehydration of alcohols can be attributed to the stabilized polymer chains and the conspicuous increase in the water adsorption from mixing with graphene oxide sheets. Results show that the simulated models agree well with the experimental works in membrane density and transfer behavior of vapor molecules, which demonstrate that the modeling tools can be applied to evaluate the performance of cross-linked mixed matrix membranes, and to design various combination of hybrid membranes.

In this study, the transport performance of water molecules and the ion-rejection ability of cyclic peptide nanotubes (CPNTs) were examined on a molecular level via a simulation of forward osmosis (FO) filtration phenomena. A FO filtration model and three types of CPNTs, 8CP, Mba-8CP, and 4Mba-8CP (with different levels of modification by hydrophobic functional groups), were constructed via molecular dynamics (MD). MD simulation was adopted to explain the diversity transport mechanism between different types of CPNTs, and to analyze how hydrophobic modified functional groups affect the FO filtration process. The hydration structures of cations and anions were validated via radial distribution function (RDF) and hydration analysis. The interaction energy of van der Waals (vdW) and coulombic energies at the interface between water molecules and the first cyclic peptide cage suggested that hydrophobic modified functional groups reduced the interior affinity between water molecules and nanotubes, which made it difficult for water molecules to enter a nanotube. During FO filtration calculation, the alteration in the number of water molecules in each region of saltwater, pure water and membrane was traced and recorded. The osmotic pressure was considered as the driving force for concentration-driven FO process which was calculated via the Van't Hoff equation in this work. By combining the above results, water permeabilities of the three types of CPNTs could be directly calculated and compared. The results of the water permeabilities agreed well with the interaction energy analysis. Finally, the hydration structure of cations within a nanotube was used to directly study the ion rejection mechanism of CPNTs. Three types of CPNTs showed high selectively between water molecules and ions. The partial charge distribution of a cyclic peptide cage illustrated how cations are trapped within nanotubes. A microscopic view of this information was informative in the analysis of nanotube properties and in the application of CPNTs to the filtration process.

Physical absorption is a commercial technology for the capture of high concentration carbon dioxide and features low energy requirement for solvent regeneration. The application of physical absorption for the capture of low concentration carbon dioxide from fossil fuel power plants requires improvement in the absorption efficiency. A novel hybrid absorption/stripping membrane contactor (HASMC) with parallel and contiguous configurations is proposed and studied for carbon dioxide absorption by propylene carbonate. Employing parallel-type and contiguous-type HASMCs, the experimental results show substantial enhancement of absorption flux relative to pure absorption operation with an enhancement factor of 1.16–1.61 and 1.55–2.21, respectively. Simulation work reveals the concentration boundary layers in the liquid channel and explains the mechanisms of absorption enhancement for both configurations. Both experimental and simulation results show increase of absorption flux with the increase of liquid velocity, flue gas velocity and flue gas carbon dioxide concentration. This study has shown that HASMCs with contiguous configuration can be high efficiency membrane contactors.

In this study, we proposed a cost-effective method for preparing graphene nano-flakes (GNFs) derived from carbon nanotubes (CNTs) via three steps (pressing, homogenization and sonication exfoliation processes). Scanning electron microscopy (SEM), transmission electron microscopy (TEM), atomic force microscopy (AFM), laser scattering, as well as ultraviolet-visible and photoluminescence (PL) measurements were carried out. The results indicated that the size of as-synthesized GNFs was approximately 40-50 nm. Furthermore, we also used first principles calculations to understand the transformation from CNTs to GNFs from the viewpoints of the edge formation energies of GNFs in different shapes and sizes. The corresponding photoluminescence measurements of GNFs were carried out in this work.

The slow kinetics of ethanol oxidation reaction (EOR) has limited its widespread use for fuel cells. Bimetallic catalysts with optimized surface compositions can considerably govern rate-determining steps through selectivity for CH3COOH formation or by facilitating the adsorption of OHadsvia the bifunctional effect of an alloy to increase the EOR's kinetic rates. Here, we reported monodisperse ordered In-Pd nanoparticles as new bimetallic high-performance catalysts for EOR. In-Pd nanoparticles, i.e., In3Pd2 and In3Pd5 were prepared using arrested precipitation in solution, and their composition, structures, phase and crystallinity were confirmed using a variety of analyses including TEM, XPS, EDS and XRD. In-Pd nanoparticles were loaded on carbon black (Vulcan XC-72) as electrocatalysts for EOR in alkaline media. In3Pd2 and In3Pd5 nanoparticles exhibited 5.8 times and 4.0 times higher mass activities than commercial Pd/C, which showed that the presence of indium greatly boosts electrocatalytic reactivity for EOR of Pd catalysts. This performance is the best among those of bimetallic nanoparticles reported to date. Such high performance of In-Pd nanoparticles may be attributed to the following two reasons. First, In-Pd nanoparticles exhibited excellent CO anti-poison ability, as confirmed by CO striping experiments. Second, as revealed by DFT calculations of metals with OHads adsorption, In atoms on In3Pd2 surface exhibited the lowest energy (-1.659 eV) for OHads adsorption as compared to other common oxophilic metals including Sn, SnPt, Ag, Ge, Co, Pb, and Cu. We propose that the presence of indium sites promoted efficient free OH radical adsorption on indium sites and resulted in a faster reaction rate of acetate formation from acetaldehyde (the rate determining step for EOR on Pd sites). Finally, a single direct ethanol fuel cell (DEFC) with Pd/C anode was prepared. Compared to the results for a commercial Pd/C anode, the open circuit voltage (OCV) of In3Pd2/C improved by 0.25 V (from 0.64 to 0.89 V) and the power density improved by ∼80% (from 3.7 to 6.7 mW cm-2), demonstrating its practical uses as Pt or Pd catalyst alternatives for DEFC.

In this work, a zeolitic imidazolate framework-8 (ZIF-8)/polyvinyl alcohol (PVA) mixed matrix membrane (MMM) was coated onto α-aluminum oxide (α-Al2O3) hollow fibers for ethanol dehydration by utilizing the pervaporation technique. ZIF-8/PVA solution was prepared via a drying-free, water-based method to obtain a uniform distribution MMM. Before coating the MMM onto the hollow fiber, a pristine PVA solution was first dip-coated onto hollow fiber as a gutter layer to prevent phase separation. Different weight ratios of ZIF-8-loaded MMMs were prepared. The results showed that at high ZIF-8 loading (39 wt %), a high permeate flux (685 g/m2 h) and high separation factor (4821) can be observed. Furthermore, compared with free-standing ZIF-8/PVA MMMs, hollow fiber supported ZIF-8/PVA MMMs exhibit a thinner coating thickness but higher pervaporation separation index (approximately 1.5–2 times). The main contribution of this study is not only fabricated the high loading ZIF-8/PVA composite membrane with enhanced performance, but also coated onto the hollow fiber membrane which opens a gate for scale-up production.

The combination of ab initio calculation, molecular dynamics (MD) and Monte Carlo (MC) simulations was used to investigate the structural characteristics and transport behavior of PIM-Trip-TB and KAUST-PI-1 membranes. The PIM-Trip-TB and KAUST-PI-1 membranes are composed of rigid bridged Triptycene (Trip) units and are potential candidate membranes in gas separation processes. The effect of the Triptycene units on the membrane structure and gas transport behavior was analyzed in this study. Compared to the PIM-PI-1 membrane, which consists of the less rigid spirobisindane (SBI) units, the PIM-Trip-TB and KAUST-PI-1 membranes revealed larger surface areas, higher fraction free volume values, and narrower distributions of dihedral angles. Furthermore, the membrane transport properties were evaluated by investigating the adsorption isotherm, self-diffusion behavior, and selectivity of various gases on the membranes. The simulation results agreed well with experimental data, demonstrating that the combination of ab initio calculation, MD and MC simulations is a reliable tool for the characterization of membranes.

The fluid flow through a soft particle bed was studied theoretically and experimentally in this report. Several correction factors were introduced to modify the Ergun equation and account for the deformed shape and reduced volume of compressed particles in a compressible soft particle bed. To acquire the correction factors, both uni-compression tests and computational fluid dynamics simulation methods were used. The pressure drop estimated from the customized modeling equation was further compared with the experimental data obtained from a bed composed of calcium-alginate gel particles. In contrast to the conventional Ergun equation, the pressure drop estimated from the customized modeling equation was highly consistent with the experimental data. The result suggests that the customized modeling equation is a convenient tool for accurately predicting the pressure drop across a compressible soft particle bed. © 2016 American Institute of Chemical Engineers AIChE J, 62: 1716–1727, 2016

Membrane crystallization (MCr) is emerging as an interesting candidate to extract additional freshwater and raw materials from high-concentrated solutions. Traditionally, MCr has been carried out by using polymeric membranes that have limited chemical and mechanical stability. These shortcomings can be overcome by using ceramic membranes. The current study describes the preparation and testing of two hydrophobic ceramic membranes synthesized trough sol-gel process, and combined phase-inversion and sintering method. The first membrane (CM-L) was synthesized by coating hydrophobic polymethylsilsesquioxane aerogels on alumina membrane supports via a sol-gel process. The membrane showed stable hydrophobic character in membrane distillation and crystallization tests but very low flux. To obtain high flux, a second type (CM-S) membrane was prepared by applying Fluoroalkylsilanes (FAS) (1H, 1H, 2H, 2H‑perfluorooctyltriethoxysilane) hydrophobic agent at the relatively thin and more porous as-sintered alumina hollow fibers. The suitability of both membranes for MCr process was analyzed by crystallizing NaCl and LiCl. By using 1 M NaCl and 13 M LiCl aqueous solutions, and under the same operative conditions, CM-S membrane exhibited average flux higher than CM-L membrane. The performance of both the membranes, in terms of hydrophobic character, remained stable throughout the performed tests.

A semianalytical solution for a power-law fluid flowing through a conical annulus was derived to estimate the velocity profile in the axial direction, the shear rate and the elongation rate within a spinneret during the spinning of hollow fiber membranes. The angle coefficient was introduced as a new parameter to account for the effect of radial flow and to modify the governing equation, which initially neglected the effect of radial flow. The results estimated from this semianalytical solution agreed more closely with computational fluid dynamics simulation results than those obtained from the approximate analytical solution in our previous study. By accurately predicting the velocity profile in the axial direction and the shear and elongation rates in a conical annulus, the solution derived in this study is expected to provide a reliable criterion for spinneret design to achieve a specified membrane morphology with a desired performance. © 2015 American Institute of Chemical Engineers AIChE J, 61: 3489–3499, 2015

Strigolactones (SLs) are a novel class of plant hormones with enormous potential for the prevention and treatment of inflammation. To further investigate the anti-inflammatory activities of SLs, a representative SL, GR24, and the reductive products of its D-ring were synthesized and their anti-inflammatory activities were fully evaluated on both in vitro and in vivo models. Among these compounds, the two most active optical isomers (2a and 6a) demonstrated strong inhibitory activity on the release of inflammatory cytokines, including nitric oxide (NO), tumor necrosis factor-alpha (TNF-α), and interleukin-6 (IL-6) by blocking the nuclear factor kappa B (NF-κB) and mitogen-activated protein kinase (MAPK) signaling pathways; they also greatly inhibited the migration of neutrophils and macrophages in fluorescent protein labeled zebrafish larvae. These results identified the promising anti-inflammatory effects of SLs, and suggested that both the absolute configuration of SL and the α,β-unsaturated D-ring structure are essential for the observed anti-inflammatory activity.

Worldwide water scarcity and an increase in population growth have become unprecedented urgent global issues. There is a pressing need to develop robust membrane technologies for water and wastewater treatment at lower cost. Inorganic membranes feature superior chemical, thermal, and mechanical robustness as well as reusability. They are ideally suited for harsh environments in many wastewater treatment applications. Common fabrication methods of inorganic membranes include slip casting, tape casting, pressing, extrusion, dip coating, sol-gel process, atomic layer deposition, and thermal spray. For the fabrication of inorganic hollow fiber membranes, the combination of phase inversion and sintering is used. The excellent packing density and high specific area of inorganic hollow fiber membranes can offer great treatment capacities for large-scale applications. Commercial inorganic membranes have been applied in a wide variety of industrial applications and to compete with polymeric counterparts on a whole-life cost basis. Recent progress in inorganic membrane science and technologies have shown great potential in many water treatment applications, including potable water production, desalination, wastewater treatment, as well as juice clarification and concentration.

Objective: A method based on high pressure digestion andinductively coupled plasma mass spectrometry (ICP-MS) detection was establishedfor determination of arsenic, mercury, lead, cadmium, chromium and thallium inbiological tissues. Method: The samplesof hair, nails, viscera, blood, urine were digested with HNO3 and H2O2in high pressure digestion tank ; Indium was used as internal standard element,The certified GBW07601a (CRM Human Hair) was adopted as the quality control forthe whole processes. Results: Theexcellent sensitivity and reliability were demonstrated by the method ofrecovery 82% ~ 110%, RSD (n = 5) less than 5% and the linear range of 0.020ng/mL to 100 ng/mL (r > 0.99). The prototype measurements are within thescope of the standard value. Standard addition recovery of the six elements is therange of 92% ~ 105%. Conclusion: Arapid, easy and accurate quantitative ICP-MS method was established fordetermination of toxic elements in the human body, which enrich the existing meansof forensic technology. At the same time, this work provide the most practicaland reliable core data for poisons metabolism and pathological study.

For the lack of adaptability about the existing concurrency control algorithms, adaptive decision concurrency control algorithm is proposed. ADCC algorithm divides concurrency control process into two phases in: execution authorizing phase and strategy selecting phase. In execution authorizing phase, algorithm compares statistics and effectiveness of transactions to determine the execution order of conflict transactions. In strategy selecting phase, according to transactions’ read/write status and current conflict rate, algorithm selects optimistic/pessimistic conflict resolution strategy adaptively. Such selection mechanism makes ADCC algorithm have high efficiency no matter database system is busy or idle. Simulation experiment proves that ADCC algorithm this paper proposed is superior to classical strict two phases locking algorithm and hybrid concurrency control. So ADCC algorithm performs well in the period of concurrency control.

Analytical solution of solute concentration for the systems of dialysis coupled with ultrafiltration in cross-flow membrane modules was obtained by the method of perturbation, and thus separation efficiencies could be calculated for various operating and design conditions. The overall mass transfer coefficient was assumed to be constant and the concentration polarization and pressure drop on both compartments were neglected in solving this problem. Moreover, the mean values of permeation flux and sieving coefficient were taken and were treated as constant. It was found that increasing the flow rate in retentate phase is more beneficial to the mass transfer than increasing in dialysate phase. The performance of dialysis can be improved significantly by the effect of ultrafiltration, especially for the systems with low mass transfer coefficient. The present analysis could be applied to all kinds of configurations, such as parallel-flow, radial-flow and spiral-wound types, but with the limitations of laminar flow and low viscosity and high diffusivity of the fluids.

iASPP can prompt the cell proliferation and inhibit the apoptosis of many cells. There are putative binding sites of transcription factor GATA-2 upstream of iASPP transcription start site. GATA-2 plays an important role in the proliferation and differentiation of hematopoietic stem cells (HSC) and progenitors. This study was aimed to explore the role of GATA-2 protein in iASPP gene transcription. Firstly, the expression of iASPP and GATA-2 protein in some leukemia cell lines was detected by Western blot. Second, The expressive vector of pCMV5-GATA2 and the luciferase reporter vectors containing possible binding sites of GATA-2 were constructed and co-transfected into HEK293 and CV-1 cells. Then the luciferase activity was assayed by luminometer. Also, ChIP assays were performed to further confirm the specific binding of GATA-2 to iASPP promoter. The results showed that GATA-2 was overexpressed in most cell lines with high level of iASPP. GATA-2 exhibited a significant effect on luciferase activity of reporter gene iASPP and in a dose-dependant manner. The relative luciferase activity was up-regulated to about two-fold of the empty vector control when the transfection dose of pCMV5-GATA2 plasmid was increased to 100 ng. While the effect was more significant in CV-1 cells and showed a 6.7-fold increase. The ChIP assay demonstrated the in vivo specific binding of GATA-2 to iASPP. The binding sites of GATA2 were located between nt -361 ∼ -334 in upstream of iASPP gene transcription start site. It is concluded that transcription factor GATA-2 can bind with the cis-regulatory region of the iASPP promoter and up-regulate iASPP expression.

To investigate the expression of PTEN (phosphatase and tension homology deletion on chromosome 10, PTEN) and its pseudogene PTENP1 in acute leukemia (AL) and correlation between them, and to explore the role of PTENP1 on the PTEN expression in AL cells.PTEN and PTENP1 mRNA expression were evaluated in bone marrow (BM) samples from 138 newly diagnosed AL patients and 15 healthy controls by quantitative real-time RT-PCR (qRT-PCR). pCDH1-PTENP1 3'UTR-GFP lentivirus vectors were constructed. 293T cells were transfected by calcium phosphate precipitation to produce retrovirus. HL-60 cell line was infected with the retroviral vectors expressing pCDH1-GFP and pCDH1-PTENP1 3'UTR-GFP respectively. The flow cell sorter was used to sort the HL-60 with GFP positively expressed. The mRNA expression of PTEN and PTENP1 was detected by qRT-PCR, the expression of PTEN protein by western blot, and the impact of PTENP13'UTR on the proliferation of HL-60 cells by MTT assay.AML patients showed significantly lower PTEN and PTENP1 mRNA expression in BM compared to healthy controls. Correlation analysis showed that the expression of PTEN and PTENP1 mRNA were positively correlated (P0.05). The 108 cases of PTENP1(+) AML were classified according to the prognostic classification of 2011 NCCN Clinical Practice Guidelines in AML, there was no difference among different subgroups. HL-60 cell line was infected with the retroviral vectors expressing pCDH1-GFP (control group) and pCDH1-PTENP1 3'UTR-GFP respectively. Compared with the control group, PTENP1 mRNA level of HL-60 infected with the retroviral vectors expressing pCDH1-PTENP1 3'UTR-GFP increased significantly, and PTEN mRNA level also increased. While the PTEN protein level and the cell growth rate of the PTENP1 3'UTR group didn't change significantly.PTEN and PTENP1 mRNA expression level of BM cells from AL patients is significantly lower. There is a positive correlation between expression of PTEN and PTENP1 mRNA. PTENP1 may regulate the expression of PTEN in mRNA level.

The purpose of this study was to investigate the effect and molecular mechanism of metformin (Met) on biological characteristics of acute promyelocytic leukemia (APL) cell line NB4. NB4 cells were treated with various concentrations of Met for different time, MTT method was used to detect cell proliferation, the alteration of cell apoptosis was analyzed by flow cytometry, and the change of cell adhesion ability was examined by cell adhesion assay. NB4 cells were pretreated with U0126, a specific inhibitor for extracellular signal-regulated kinase (ERK) phosphorylation, ERK phosphorylation was assessed by Western blot analysis, apoptosis and cell adhesion ability were evaluated by flow cytometry and cell adhesion test respectively. The results showed that Met could inhibit the cell proliferation, induce the cell apoptosis and increase the ability of cell adhesion. The pretreatment of NB4 cells with 5 µmol/L U0126 could effectively inhibit the phosphorylation of ERK, and reduce cell apoptosis and adhesion induced by 5 mmol/L Met. It is concluded that Met can inhibit the proliferation and promote the apoptosis and adhesion of NB4 cells. MEK/ERK signaling pathway may be one of the molecular mechanisms of metformin on NB4 cells.