Study of antidiabetic activity of two novel Schiff base derived dibromo and dichloro substituted compounds in streptozotocin-nicotinamide-induced diabetic rats: pilot study

Abstract Schiff bases are aldehyde-or ketone-like chemical compounds in which an imine or azomethine group replaces the carbonyl group. Such compounds show various beneficial biological activities, such as anti-inflammation and antioxidants. The present study addresses comprehensiveevaluation of antidiabetic effect of two novel dibromides and dichlorides substituted Schiff bases substituted Schiff bases (2,2'-[1,2-cyclohexanediylbis (nitriloethylidyne)]bis[4-chlorophenol] (CNCP) and 2, 2'-[1,2-cyclohexanediylbis(nitriloethylidyne)]bis[4-bromophenol] (CNBP) with two different doses, high (LD) and low (LD) in streptozotocin and nicotinamide induced diabetic rats. The rats were separated into normal, untreated, treated and reference groups. Except for the normal group, diabetes traits were induced in the rest animals. Insulin level was measured, and the effect of the compounds on biochemical parameters of liver function and lipid profile were evaluated. High glucose and decreased insulin level are observed in the groups. The histological evaluation confirms that the hepatic architecture in the treated animals with a low dose of CNCP is quite similar to that of the normal hepatic structure and characterized by normal central vein, hepatocytes without any fatty alterations and mild red blood cell infiltration. CNCP (LD) and CNBP (HD) are more successful in enhancing cell survival in the diabetic rat's liver and can be responsible for causing much healthier structure and notable morphology improvement.

Effects of VALD-3,a derivative of o-vanilla Schiff base ligand,on proliferation,migration and apoptosis of colorectal cancer cells and its mechanism / 中国生物制品学杂志

@#Objective To the effects of VALD-3,a derivative of o-vanilla Schiff base ligand,on proliferation,migration and apoptosis of colorectal cancer cells and evaluate its mechanism.Methods HT-29 and HCT116 cells were cultured in vitro,and the inhibitory effects of VALD-3(5,10,20 and 40 mg/L) on proliferation of the two kinds of cells were detected by MTT assay;The effects of VALD-3(10,20 and 40 mg/L) on the morphological changes of the cells were observed by inverted microscope,while the effects on the migration ability of HT-29 cells were detected by cell scratch test,and the effects on the apoptosis of HT-29 cells were detected by flow cytometry and Hoechst 33258 fluorescence staining;The effects of VALD-3(5,10,20 and 40 mg/L) on the expression of apoptosis-related proteins in HT-29 cells were detected by Western blot.Negative control groups were set up(with no VALD-3).Results Compared with the negative control group,the survival rates of HT-29 and HCT116 cells in 10,20 and 40 mg/L VALD-3 treated groups significantly decreased(t=7.717～2 006.148,each P <0.05);the number of HT-29 and HCT116 cells in 10,20 and 40 mg/L VALD-3groups decreased significantly with the increase of VALD-3 concentration,the cells appeared irregular morphology and gradually became round and smaller,and cell fragments increased;In 10,20 and 40 mg/L VALD-3 treated groups,the migration rate of HT-29 cell scratches decreased significantly(t=7.596～73.780,each P <0.01),the apoptosis rate increased significantly(t=7.092～8.057,each P <0.01),and the number of apoptotic cells increased significantly with strong bright blue fluorescence,chromatin concentration and nuclear fragmentation;The levels of cleaved caspase-3 and Bax protein in HT-29 cells treated with 5,10,20 and 40 mg/L VALD-3 significantly increased(t=2.998～24.901,each P <0.05),the level of Bcl-2 protein in 40 mg/L VALD-3 group decreased significantly(t=10.035,P <0.05),and the levels of cleaved caspase-8 in 20 and 40 mg/L VALD-3 group significantly increased(t=12.630 and 8.064 respectively,each P <0.01).Conclusion VALD-3 inhibited the proliferation and migration of colorectal cancer cells and induced apoptosis by regulating the expression of cleaved caspase-3,cleaved caspase-8,Bax and Bcl-2 proteins.

Molecular docking and Antibacterial activities of Cobalt (II) complexes derived from precursors of Hydrazones

The Schiff base ligands in their deprotonated forms have been utilized to synthesize thermodynamically and kinetically stabilized Cobalt(II) complexes. In the complexes, cobalt ion present is in distorted octahedral arrangement and is coordinated by four tridentate ligands in complexes. The synthesized Schiff base ligands coordinate with Cobalt (II) ion through four azomethine nitrogen atoms and two sulfur atoms developing a 6- membered chelate ring. Synthesized Cobalt(II) complexes via hexadentate ligands have been characterized thoroughly through various spectroscopic techniques like FT-IR, UV-Vis, 1HNMR, TGA, TEM, SEM, Particle size, Elemental analysis (C, H, N, Co, S) and conductivity measurements. All Cobalt(II) complexes have been evaluated for in vitro antimicrobial activity against isolated bacterial strains of E. coli (MTCC-1687), E. faecalis (MTCC-439), S. aureus (MTCC-737) and MR S. aureus (Indigenous). All Cobalt complexes show mild to moderate antibacterial activity. The MIC ranged from 50 µg/ mL to 3.125 µg/ mL. All Cobalt(II) complexes displayed in-vitro antibacterial activity against both gram-positive and gram-negative bacterial strains. It may be proved that the antibacterial activity of the complexes is related to the cell wall structure of the tested bacteria. In-vitro toxicity tests explained the Cobalt complexes were less cytotoxic than the Vancomycin drug on A431 cancer cell lines and the results explain that synthesized Cobalt complexes can act as potent antimicrobial agents and can be considered as a good drug candidate for medicinal chemistry researchers.

A Schiff base of 2-((E)-(2-amino-5-methylphenylimino)methyl)- 5-(difluoromethoxy)phenol and its applications on fluorescent chemosensor for selection of Mg2+ ion, molecular docking, and anticancer activity

A novel Schiff base of 2-((E)-(2-amino-5-methylphenylimino)methyl)-5-(difluoromethoxy)phenol (R) wassynthesized and characterized by FTIR, 1H&13C-NMR, and mass spectrometry. The receptor turned yellow and thengreen in the presence of Mg2+ molecules, with the intervention of different metal ions. The selectivity and sensitivityof Mg2+ ion caused the maximum fluorescence emission intensity at 524 nm, with an excitation wavelength at 378nm. Further experiments confirmed that receptor R binds with Mg2+. Job’s plot conforms to a 1:1 stoichiometrycomplex formation. The strong fluorescence is owing to the photoinduced electron/energy transfer effect. The receptorwas recovered by an ethylenediaminetetraacetic acid titration and the emission intensity also returned to a valueequivalent to the unbound ligand. protein data bank: 4J96 was used for the molecular docking of receptor R. Thecytotoxicity effect treatment was carried out by increasing the concentration of HeLa cells to predict IC50 value. Thehighest occupied molecular orbital/lowest unoccupied molecular orbita energy gap calculated and compared betweenR results as 3.48 eV and R-Mg2+ alpha and the beta value calculated a low energy value at 2.27 eV.

Synthesis And Evaluation Of 7-(2-((Substituted Phenyl) Imino)-2-Phenylethoxy)-4-Methyl-2h-Chromen-2-Ones As Antifungal Agents

In the context of the dangerous phenomenon of antimicrobial resistance to the available drugs, we present here the synthesis and evaluation of 7-(2-((substituted phenyl) imino)-2-phenylethoxy)-4-methyl-2H-chromen-2-ones as antifungal agents. Among the compounds, SB-4 was found to be most potent against Candida albicans when compared with the reference drugs Clotrimazole and Terbinafine. The molecular properties of the newly target compounds were performed by online software, and results showed good drug-like properties. The results showed target compounds further optimized as lead compounds as anti-Candida potential.

Design

According to one pot microwave assisted synthesis, the versatile precursor 2- aminothiazole was prepared and utilized for the construction of new thiazole hybrids targeting MCF7 cell lines. 2‐amino thiazole was condensed with corresponding aldehydes to yield Schiff’sbase (2) intermediates followed by the diazo coupling reaction furnished the designed hybrids(3) contains azo-methine and diazo linkages in its structures. The newly synthesizedcompounds were confirmed on the basis of IR and H1NMR spectral analytical data. All thesynthesized compounds were evaluated for their in-vitro cytotoxicity activity against MCF-7celllines using MTT assay method. The obtained results revealed the more promising compoundsof the synthesised series, 3B and 3H with CTC50 value of 17.77±0.31μg/ml, 17.83±1.14 μg/ml.

A Highly Sensitive Fluorescent Probe for Detection of Magnesium Ion(Ⅱ) Based on Novel Schiff's Base / 分析化学

A highly sensitive fluorescent probe TZ based on a novel Schiff's base was prepared for detection of Mg2+. It was constituted by introducing dansyl chloride and 2-hydroxy-1-naphthaldehyde through amino and hydrazide groups on p-aminobenzoyl hydrazide. The recognition mechanism of the fluorescent probe TZ for Mg2+was studied by electrospray ionization mass spectrometry (ESI-MS), UV-vis and fluorescence spectra. UV-vis spectra showed that the probe TZ had a characteristic absorption peak of naphthalene aldehyde at 386. 5 nm,and a new absorption peak at 411 nm was observed after coordination between TZ with Mg2+. A sharp isobestic point was obtained at 400 nm. Fluorescence spectra showed that the emission wavelength was red-shifted to 400 nm upon the addition of Mg2+into probe TZ. The fluorescence intensity was enhanced by 10 times at the emission wavelength of 468 nm and the quantum yield of 0.57 was obtained. Moreover,chemical bond energy transfer was found when 2-hydroxy-1-naphthaldehyde was coordinated with Mg2+. When the other metal ions (Li+,Na+,K+,Zn2+,Ca2+, Mn2+, Cd2+, Pb2+, Ag+, etc.) were added into TZ, no significant change of fluorescence intensity was observed. It indicated that TZ had high selectivity to Mg2+. Furthermore, the recognition of TZ to Mg2+was not interfered by other competing metal ions. ESI-MS titration and Job's plot analysis confirmed that 1: 1 complexation stoichiometry between TZ and Mg2+was obtained. The lowest detection limit was up to 0.13 μmol/L.

A Novel Fluorescent Probe Based on Schiff Base for Dual Sensing of Zn2+and CN- / 分析化学

A novel Schiff base probe 4'-hydroxy-3'-((2-pyridin-2-ylmethylimino) methyl)-4-biphenyl carbonitrile (HPBC) for dual sensing of Zn2+and CN-was synthesized and characterized by various techniques such as UV-Vis, fluorescence, HRMS and NMR spectroscopy. HPBC was highly selective toward these two ions with different fluorescence signals in two different media. In EtOH-H2O(2:3,V/V;HEPES,pH 7.4),HPBC selectively bound Zn2+to form a 1:1 ligand/metal complex. Addition of Zn2+to the solution of HPBC resulted in a blue shift (△λ=15 nm) with a pronounced fluorescence enhancement at 468 nm, while there was no enhancement in the presence of other metal ions,especially Cd2+. HPBC displayed an"ON-OFF-ON"mode fluorescence change with alternative addition of Zn2+and EDTA. Hence, HPBC is a reversible and reusable sensor for Zn2+. The dynamic range of the assay is linear up to 4.0 μmol/L Zn2+ion and the limit of detection was 36.5 nmol/L,which was thousand fold lower than the WHO guideline (about 76 μmol/L) for drinking water. The fluorescence response of HPBC toward Zn2+was pH-dependent, and the maximal signal was observed at near neutral pH values, which makes it suitable for application in physiological conditions. Cell imaging studies demonstrate that this sensor is capable of sensing Zn2+in living cells. In DMSO-H2O (3:7,V/V) medium,addition of cyanide ion to HPBC led to deprotonation of the phenol hydrogen,resulting in a color change from colorless to pale yellow and a significant fluorescence enhancement at 510 nm. The probe exhibited high selectivity and sensitivity for CN- ion and the detection limit was 5.75×10-7mol/L. Finally,the use of a test strip of probe HPBC to detect cyanide was reported.

Molecular And 3D-Structural Characterization Of Fructose-1,6-Bisphosphate Aldolase Derived From Metroxylon Sagu

ABSTRACT Fructose-1,6-bisphosphate aldolase (FBAld) is an enzyme that catalyzes the cleavage of D-fructose-1,6-phosphate (FBP) to D-glyceraldehyde-3-phosphate (G3P) and dihydroxyacetone phosphate (DHAP), and plays vital role in glycolysis and gluconeogenesis. However, molecular characterization and functional roles of FBAld remain unknown in sago palm. Here we report a modified CTAB-RNA extraction method was developed for the isolation of good quality RNA (RIN>8) from sago leaves and the isolation of FBAld cDNA from sago palm. The isolated sago FBAld (msFBAld) cDNA has total length of 1288 bp with an open reading frame of 1020 bp and a predicted to encode for a protein of 340 amino acid resides. The predicted protein shared a high degree of homology with Class-I FBAld from other plants. Meanwhile, the msFBAld gene spanned 2322 bp and consisted of five exons. Conserved domain search identified fifteen catalytically important amino acids at the active site and phylogenetic tree revealed localization of msFBAld in the chloroplast. A molecular 3D-structure of msFBAld was generated by homology modeling and a Ramachandran plot with 86.7% of the residues in the core region, 13.4% in the allowed region with no residues in the disallowed region. The modeled structure is a homotetramer containing an (/(-TIM-barrel at the center. Superimposition of the model with Class-I aldolases identified a catalytic dyad, Lys209-Glu167, which could be involved in the Schiff's base formation and aldol condensation. Apart from that, overproduction of the recombinant msFBAld in Escherichia coli resulted in increased tolerance towards salinity.

Synthesis and antitumor activity of fluoroquinolone C-3 s-triazole Schiff-base carboxylic acid derivatives from pefloxacin (X) / 中国药科大学学报

To explore a new strategy for further optimization to the C-3 bioisteric heterocyclic ring of fluoroquinolones,twelve novel fluoroquinolone C-3 s-triazole Schiff-base carboxylic acid derivatives(7a-71) were designed and synthesized with both functionalized sulfanylacetic acid and Schiff-base moieties as the modified side-chain for the C-3 bioisosteric s-triazole ring of pefloxacin(1).The structures were characterized by elemental analysis and spectral data,and the in vitro anti-tumor activity of the title compounds against SMMC-7721,L1210 and HL60 cell lines was evaluated.The preliminary pharmacological results demonstrated that the title compounds possessed more significantly anti-proliferative activity than either the parent 1 or the corresponding amine intermediates(6).In particular,the title compound bearing a fluorine atom (7j) and compound bearing a nitro group attached to benzene ring (71) were comparable to the control doxorubicin against SMMC-7721 cells with an IC50 value of micro-molar concentration,respectively.It suggests that s-triazole ring modified with functional side-chain moieties instead of the C-3 carboxylic group is favorable to the improvement of antitumor activity.

Synthesis and Anti-HIV-1 Activity of One Schiff Base Derivative with Glucosamine of Gossypol / 中国药师

Objective: To confirm the structure and preferential conformation of the Schiff base of gossypol with 1, 3, 4, 6-tetra-O-acetyl-β-D-glucosamine and explore its anti-HIV-1 activity.Methods: The Schiff base of gossypol with 11, 3, 4, 6-tetra-O-acetyl-β-D-glucosamine was synthesized and identified by FT-IR, NMR spectroscopy and the PM6 semi-classical calculation.The inhibitory activity of the novel compound against the laboratory-adapted HIV-1IIIB strain was examined using the HIV-1IIIB/TZM-bl indicator cell culture system.Results: The 1H and 13C-NMR signals of the new Schiff base were assigned.The PM6 semi-classical calculation indicated that enamine-enamine tautomeric form of the new Schiff base was more stable,which was stabilized by the intramolecular hydrogen bonds.The anti-HIV-1 test showed that the compound could block the entry of HIV-1IIIB into the target cells.Conclusion: The Schiff base of gossypol with 1, 3, 4, 6-tetra-O-acetyl-β-D-glucosamine exhibits enamine-enamine tautomeric form in solution, which shows potential anti-HIV-1 activity.

Free Radical Scavenger Activity of Cinnamyl Chitosan Schiff Base.

In this study, new cinnamyl chitosan schiff base was evaluated as antioxidant material. Antioxidant activity was measured by two different popular methods (uninhibited/inhibited hyaluronan degradation and decolorization of ABTS methods). the results show decrease the hydrogen donation behavior of chitosan after coupling with cinnamaldehyde, in the other hand, ABTS method show increase the electron donation activity of cinnamyl chitosan than the chitosan itself.

Spectral, Magnetic and Biological Studies of ZnII Complexes of Schiff Bases Derived From 4-(O-Methoxyphenyl)-2-Aminothiazole.

In the present ZnII complexes of Schiff bases (SB-1 to SB-7) derived form 4-(o-methoxyphenyl)-2-aminothiazole and R substituted salicylaldehyde (R = H, 3-Me, 4-Me, 5-Me, 3-OMe and 5-Br) and 2-hydroxy-1-naphthaldehyde o-hydroxyaldehydes were synthesized, characterized and tested for the bioactivity against Gram positive and Gram negative group of organisms. The as-synthesized complexes were characterized by elemental, spectral and spectroscopic methods for measuring magnetic susceptibility, conductivity and assayed for biological activities. The complexes showed 1:2 metal : ligand stoichiometry (ML2) and an octahedral geometry. The complexes showed an antibacterial activity against Bacillus subtilis 2063 and Escherichia coli 2931, and antifungal activity by preventing the dimorphic switching in Candida albicans.

Study on antitumor effect of a novel schiff base ruthenium coordination compound / 中国生化药物杂志

Objective To study effect of a novel schiff base ruthenium coordination compound on cell proliferation and apoptosis of gastric cancer SGC-7901 cell.Method Gastric cancer SGC-7901 cell were divided into four groups according to different treatment of novel schiff base ruthenium coordination compound (concentration of 10, 30, 50μmol/L) and blank group with DMSO.Cell proliferation was detected by MTT assay, cell apoptosis and cell cycle were analysed by flow cytometry.ResuIts MTT results showed the inhibitory effect of novel schiff base ruthenium coordination compound on SGC-7901 cell enhanced with the increase of its concentration, and inhibitory rates were higher than that of blank group at 24, 48, 72 h.Flow cytometry results showed the apoptosis rate of novel ruthenium coordination compound groups of 10, 30, 50μmol/L were (17.64 ±1.21)%, (26.47 ± 0.61)%, (55.63 ±1.49)%, respectively, all higher than that of blank group (P<0.05).The cell proportion of G1 phase increased with the increasing of the novel schiff base ruthenium coordination.ConcIusion A novel schiff base ruthenium coordination compound could inhibit the growth of gastric cancer SGC-7901 cells, promote apoptosis and arrest gastric cancer SGC-7901 cells at G1.

Benzaldehyde levofloxacin schiff base induces apoptosis of human hepatocarcinoma cells / 中国药理学通报

Aim To study the effect of (S) -1, 8-(2-methyl phosphate ethoxy )-6-fluorine-7-( 4-methyl- pi-perazine-1-base )-3-[ S-benzyls-based-4-( for nitroben-zene methylene group amino )-1 , 2 , 4-all triazole-3 base]-quinoline ( 1-H )-4-ketone ( M18 ) on apoptosis of hepatocarcinoma SMMC-7721 cells in vitro. Meth-ods With different concentrations of M18 at different time used to treat SMMC-7721 cells, human breast cancer MB-231cells, human colon cancer HCT-116 cells, human hepatocarcinoma HEPG-2 cells, mouse bone marrow mesenchymal stem cells ( BMSCs ) in vitro,the inhibition effects of M18 on cell proliferation were examined by MTT assay. Cell apoptosis was de-termined using Hoechst 33258 fluorescence staining and TUNEL method. Mitochondrial membrane poten-tial (△ψm ) was measured using a high content screening image system. Protein expression of caspase-3 , p53 and cytochrome C was detected with Western blot analysis. Results Treatment with M18 ( 4 ~32μmol·L-1 ) potently inhibited the proliferation of the cancer cells in time-and dose-dependent manners ( the IC50 value at 24 h in SMMC-7721 cells, MB-231cells, HCT-116 cells and HEPG-2 cells was 8. 65 μmol · L-1 , 9. 37 μmol · L-1 , 12. 74 μmol · L-1 and 9. 40μmol · L-1 , respectively ) . In contrast, M18 had weak cytotoxicity against BMSCs with IC50 value of 38. 96 μmol·L-1 . Levofloxacin had weak cytotoxicity against SMMC-7721 cells with IC50 value of 735. 10μmol·L-1 . Treatment of SMMC-7721cells with differ-ent concentrations of M18 for 24 h increased the per-centage of the apoptosis cells ( P <0. 05 ) and de-creased the mitochondrial membrane potential. In ad-dition, M18 increased protein expression of p53, caspase-3 and the cleaved activated forms of caspase-3 in SMMC-7721 cells. Treatment of SMMC-7721 cells with M18 significantly increased cytochrome C in the cytosol, and decreased cytochrome C in the mitochon-drial compartment. Conclusion The mitochondrial-dependent pathways are involved in M18 induction of apoptosis of SMMC-7721 cells.

Synthesis of 10-Position Schiff Base Derivatives of Emodin and Preliminary Investigation of Anti-tumor Ac-tivity in vitro / 中国药师

Objective: To synthesize 10-position schiff base derivatives of emodin and study the anti-tumor activity. Methods:The 10-position schiff base derivatives of emodin were synthesized through emodin reacting with ammonia derivatives in absolute alcohol with acetic acid as the catalytic agent. Their structures were characterized by 1 H-NMR and ESI-MS, and the anti-tumor activity on k562 cells was determined by MTT method. Results:Three 10-position schiff base derivatives were synthesized and the structures were confirmed, and the IC50 on k562 cells was 4. 5, 3. 8 and 2. 0 μmol·L-1 , respectively. Conclusion:The 10-position schiff base de-rivatives of emodin can improve the anti-tumor activity and druggability of the parent compound, which are worthy of further study.

A novel schiff base zinc coordination compound inhibits proliferation and induces apoptosis of human osteosarcoma cells / 华中科技大学学报（医学）（英德文版）

Various kinds of schiff base metal complexes have been proven to induce apoptosis of tumor cells. However, it remains largely unknown whether schiff base zinc complexes induce apoptosis in human cancer cells. Here, we synthesized a novel schiff base zinc coordination compound (SBZCC) and investigated its effects on the growth, proliferation and apoptosis of human osteosarcoma MG-63 cells. A novel SBZCC was synthesized by chemical processes and used to treat MG-63 cells. The cell viability was determined by CCK-8 assay. The cell cycle progression, mitochondrial membrane potential and apoptotic cells were analyzed by flow cytometry. The apoptosis-related proteins levels were determined by immunoblotting. Treatment of MG-63 cells with SBZCC resulted in inhibition of cell proliferation and cell cycle arrest at G1 phase. Moreover, SBZCC significantly reduced the mitochondrial membrane potential and induced apoptosis, accompanied with increased Bax/Bcl-2 and FlasL/Fas expression as well as caspase-3/8/9 cleavage. Our results demonstrated that the synthesized novel SBZCC could inhibit the proliferation and induce apoptosis of MG-63 cells via activating both the mitochondrial and cell death receptor apoptosis pathways, suggesting that SBZCC is a promising agent for the development as anticancer drugs.

Synthesis, Characterization and evaluation of Anti-inflammatory and Analgesic activity of Benzothiazole derivatives.

A parent benzothiazole nucleus was synthesized by para amino acetanilide, then it is subjected to treatment with various substituted aromatic aldehydes to get the corresponding Schiff’s bases followed by treatment with pthalic anhydride to form 2-(6- acetamidobenzo[d]thiazol-2-ylcarbamoyl)benzoic acid. The structures of synthesized compounds were confirmed by various spectroscopic methods such as IR, 1H NMR and mass spectroscopy. The products were evaluated for their anti-inflammatory and analgesic activities. Some of the compounds exhibited potent activities when compared with the standards.

Antioxidant activity of novel 4-oxo-azetidine derivatives synthesized from schiff bases.

The synthesized 4-Oxo-Azetidines which are established by spectral and analytical data are evaluated for their antioxidant activity. The activity of all compounds is identified by using nitricoxide and superoxide radical scavenging methods against Alkaline Dimethyl Sulphoxide (DMSO). The derivatives with chlorine substituent either at ortho or para on phenyl ring exhibited maximum activity in both methods. Least activity is shown by the compound having ortho nitro group on benzene ring.

Determination of Pb(Ⅱ) Based on Dehydroabietylamine Schiff Base-Multi-walled Carbon Nano-tubes Modified Glassy Carbon Electrode / 分析化学

A novel electrochemical method based on dehydroabietylamine schiff base( DBS) and multi-walled carbon nano-tubes( MWCNTs) composite modified glassy carbon electrode was presented for determination of Pb2+. The electrochemical behaviors of Pb2+on the modifled electrode were investigated by cyclic voltammetry ( CV) and differential pulse anodic stripping voltammetry ( DPASV ) . The results showed that under the optimized conditions including 0 . 2 mol/L NaAc-HAc used as supporting buffer ( pH 5 . 5 ) , -1 . 1 V of accumulating potential, 250 s of accumulating time, the oxidation peak current was proportional to Pb2+concentration in the range between 1 × 10-8 mol/L and 1 × 10-6 mol/L with the linear regression equation as I(μA)= 6. 6173c(μmol/L)+0. 2597(R=0. 9971) and the detection limit as 5. 0×10-9 mol/L (S/N=3). The proposed sensor was successfully employed to determine Pb2+ in real samples with satisfactory results. In addition, this method showed the advantages of simple operation, short assay time, good accuracy, satisfactory efficiency and good selectivity for determination of low concentration lead in water samples.