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	1. MALDI-TOF-MS Analysis of Small Molecules Using Modified Mesoporous Material SBA-15 as Assisted Matrix
	Xiuhua, Li,Xue, Wu,Donghao, Li
	Chemistry 06 April 2009
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	Abstract:Mesoporous silica, SBA-15 has been successfully functionalized with quinoline moiety and applied to MALDI-TOF-MS analysis of small molecules as a matrix. The modified SBA-15 material (SBA-15-8-(3-(triethoxysilyl)propoxy)quinoline, SBA-15-8QSi) were obtained by using calcined SBA-15 and 8-hydroxyl quinoline. The structure of the functionalized mesoporous was systemically characterized with TEM technique, N2 adsorption-desorption isotherms technique and FT-IR spectra. Compared with DHB and SBA-15, it is demonstrated several advantages in the analysis of low molecules with MALDI-TOF-MS, such as less background interference ions, high homogeneous, better reproducibility etc. Base on these results, the various kinds of effect parameters were optimized. The ideal operation conditions are 1) methanol used as dissolving solvent; 2) sample first dropping method; 3) ratio between the analyte and matrix is 3.5:10. Under the optimization conditions, it gives low detection limit (0.1 fg for sucrose) and high reproducibility (≤29%). And the technique was successfully applied in analysis of low molecular saccharides and natural honey.
	TO cite this article:Xiuhua, Li,Xue, Wu,Donghao, Li. MALDI-TOF-MS Analysis of Small Molecules Using Modified Mesoporous Material SBA-15 as Assisted Matrix[OL].[ 6 April 2009] http://en.paper.edu.cn/en_releasepaper/content/31086


	2. Identification and Quantification of Volatile and Semi-volatile Chemicals by Gas Flow Headspace-Liquid Phase Micro Extraction
	Cui Yang,Chunyan Ren,Jinxue Qiu,Donghao Li
	Chemistry 01 April 2009
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	Abstract:In order for extraction and analysis of volatile and semi-volatile chemicals from sample matrix, simple gas flow headspace-liquid phase microextraction (GF-HS-LPME) method was developed. Based on the original HS-LPME technique, gas flow procedure was added to increase enrichment factor. The GF-HS-LPME parameters such as gas flow rate, heating and cooling temperature, extraction time and position of solvent microdrops etc were optimized. In comparison to steam distillation, the new method is simpler in sample preparation, requires less sample mass, and produces better repeatability (RSD < 20%) and shortens extraction time. This method provides also high stability for water, oxygen and thermally unstable chemicals. It is important to note that this new method was able to detect three hydrolysis compounds such as triphenyl Phosphoric ester, (2-isopropyl)phenyl diphenyl phosphoric ester and tri(2-isopropylphenyl) phosphoric ester from Wild Millet whereas the steam distillation method was not able to detect those compounds. Under the optimized conditions, detection limit (S/N) was 0.020~200 ng for PAHs which was 10 times higher than those in original HS-LPME. Therefore, it is concluded that the GF-HS-LPME is a simpler, faster and more economical method than the conventional steam distillation technique for intact determination of volatile and semi -volatile chemicals from environmental samples.
	TO cite this article:Cui Yang,Chunyan Ren,Jinxue Qiu, et al. Identification and Quantification of Volatile and Semi-volatile Chemicals by Gas Flow Headspace-Liquid Phase Micro Extraction[OL].[ 1 April 2009] http://en.paper.edu.cn/en_releasepaper/content/30962

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	3. Electrochemical and Spectrometric Studies of Double Strand Calf Thymus Gland DNA Denatured by Al(III) at Neutral pH
	Fuping Zhang,Qing Cao,Jiongjia Cheng,Caihua Zhang,Na An,Shuping Bi
	Chemistry 13 January 2009
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	Abstract:The interaction between double strand calf thymus gland DNA (ds-DNA) and Al(III) was studied by differential pulse voltammetry (DPV) at a hanging mercury drop electrode (HMDE), Raman spectrometry and circular dichroism (CD) spectra. It was shown that at neutral pH ds-DNA did not produce any cathodic peak at the HMDE in the potential window from -550 mV to -2000 mV vs. SCE. However, in the presence of Al(III), a cathodic peak generated at about -1660 mV, which is ascribed to the reduction of adenine and cytosine residues of the denatured DNA (d-DNA). It was concluded that ds-DNA was denatured to single d-DNA completely by Al(III) at neutral pH. The apparent denaturing kinetic velocity constants of ds-DNA by Al(III) were derived from the linear increases of the cathodic peak currents with the time. When the concentration product [[Al(III)]×[OH-]^3>= 2×10^(-26), the precipitation of Al(OH)3 was observed and identified by the Raman spectrum and inductively coupled plasma atomic emission spectrometry (ICP-AES). CD spectra showed that the B-type of structure conformations of ds-DNA and related d-DNA did not change with the increment of Al(III) from 5.0×10^(-7) to 1.0×10^(-5) M, but the corresponding absorption strengths increased. The related physiological significances and possible application of the observations were discussed.
	TO cite this article:Fuping Zhang,Qing Cao,Jiongjia Cheng, et al. Electrochemical and Spectrometric Studies of Double Strand Calf Thymus Gland DNA Denatured by Al(III) at Neutral pH[OL].[13 January 2009] http://en.paper.edu.cn/en_releasepaper/content/27717


	4. Spectroscopic investigation of interaction between mangiferin and bovine serum albumin
	Hui Lin,Jingfeng Lan,Min Guan,Fenling Sheng,Haixia Zhang
	Chemistry 08 January 2009
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	Abstract:The mechanism of interaction between mangiferin (MA) and bovine serum albumin (BSA) in aqueous solution was investigated by fluorescence spectra, synchronous fluorescence spectra, absorbance spectra and Fourier transform infrared (FT-IR) spectroscopy. The binding constants and binding sites of MA to BSA at different reaction time were calculated and the distance between the MA and BSA was estimated to be 5.20 nm based on Föster’s theory. In addition, synchronous fluorescence and FT-IR measurements revealed that the secondary structures of the protein changed by the interaction of MA with BSA. Furthermore, the influence of β-cyclodextrin on the system was studied. As a conclusion, the interaction between the anti-diabetes Chinese medicine MA and BSA was studied preliminary which may provide some significant information for the mechanism of the chinese traditional medicine MA on the protein level to cure diabetes or other diseases.
	TO cite this article:Hui Lin,Jingfeng Lan,Min Guan, et al. Spectroscopic investigation of interaction between mangiferin and bovine serum albumin[OL].[ 8 January 2009] http://en.paper.edu.cn/en_releasepaper/content/27467


	5. Analysis of Sulfamerazine in Pond Water and Several Fishes by High-Performance Liquid Chromatography Using a Molecularly Imprinted Solid-Phase Extraction
	Guo Linyuan ,Jiang Xiaoman ,Zhang Cailing ,Zhang Haixia
	Chemistry 28 February 2008
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	Abstract:The synthesis and evaluation of a molecularly imprinted polymer (MIP) as a selective solid-phase extraction sorbent, coupled to high-performance liquid chromatography (HPLC), for the efficient determination of sulfamerazine (SMR) in pond water and three fishes are reported. The polymer was prepared using SMR as the template molecule, methacrylic acid as the functional monomer and ethylene glycol dimethacrylate as the cross-linking monomer in the presence of tetrahydrofuran as the solvent. The SMR-imprinted polymers and non-imprinted polymers were characterized by FT-IR and the static adsorption experiments. The prepared SMR-imprinted material showed high adsorption capacity, significant selectivity and good site accessibility. The maximum static adsorption capacity of the SMR-imprinted and non-imprinted material for SMR was 108.8 and 79.6 mg g-1, respectively. The relatively selective factor value of this SMR-imprinted material was 1.6. Several parameters influencing the solid-phase extraction process were optimized. At last, the SMR-imprinted polymers were used as the sorbent in solid-phase extraction to determine SMR in pond water and three fishes with satisfactory recovery. The limit of detection (LOD) for SMR was 1 ng g-1 and the limit of quantitation (LOQ) was 3.5 ng g-1.
	TO cite this article:Guo Linyuan ,Jiang Xiaoman ,Zhang Cailing , et al. Analysis of Sulfamerazine in Pond Water and Several Fishes by High-Performance Liquid Chromatography Using a Molecularly Imprinted Solid-Phase Extraction[OL].[28 February 2008] http://en.paper.edu.cn/en_releasepaper/content/18913


	6. Solubilization and refolding with simultaneous Purification of Recombinant Human Granulocyte Colony-stimulating Factor expressed by Escherichia coli as Inclusion Bodies
	Wang Chaozhan ,Wang Lili ,Geng Xindu
	Chemistry 06 January 2008
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	Abstract:Recombinant human granulocyte colony-stimulating factor (rhG-CSF) was solubilized and purified from inclusion bodies expressed in Escherichia coli. Effect of both pH and urea on the solubilization of rhG-CSF inclusion bodies were investigated, the results indicate that the existence both ionic and hydrophobic interactions in the inclusion bodies. Various solvents with reduced/oxidized glutathione (GSH/GSSG) were used to solubilize rhG-CSF inclusion bodies，the extent of solubilization was compared with each other and the behaviors of rhG-CSF in high performance hydrophobic interaction chromatography (HPHIC) were investigated. Solubilization of rhG-CSF inclusion bodies by 2% Sarkosyl in the presence of GSH/GSSG probably helps oxidizing rhG-CSF to form disulfide bonds, but Sarkosyl in the solution interferes seriously with the chromatographic process. To solubilize rhG-CSF inclusion bodies by combination of 2% Sarkosyl and 8.0 molL-1 urea can overcome this problem very well. And the so solubilized rhG-CSF was simultaneously refolded and purified by one step of HPHIC, with a specific activity of 1.9 × 108 IUmg-1 and a purity of 97%, the mass recovery was 41%.
	TO cite this article:Wang Chaozhan ,Wang Lili ,Geng Xindu . Solubilization and refolding with simultaneous Purification of Recombinant Human Granulocyte Colony-stimulating Factor expressed by Escherichia coli as Inclusion Bodies[OL].[ 6 January 2008] http://en.paper.edu.cn/en_releasepaper/content/17777


	7. Enzyme Functionalized Single-Walled Carbon Nanotubes and Its Application for Glucose Biosensor
	Xiaoying Yang ,Yanfeng Ma,Yanhong Lu , Yongsheng Chen
	Chemistry 15 December 2007
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	Abstract:In this paper, glucose oxidase (GOx) was covalently immobilized on the single-walled carbon nanotubes (SWNTs) via carbodiimide bond by forming amide linkages between the residual amine of GOx and carboxylic acid groups on the SWNTs tips. The functionalized SWNTs were successfully immobilized on the surface of a glassy carbon (GC) electrode. The modified electrode with SWNTs and SWNTs-GOx showed excellent quantitative response of reduction current for the determination of H2O2 and glucose, respectively.
	TO cite this article:Xiaoying Yang ,Yanfeng Ma,Yanhong Lu , et al. Enzyme Functionalized Single-Walled Carbon Nanotubes and Its Application for Glucose Biosensor[OL].[15 December 2007] http://en.paper.edu.cn/en_releasepaper/content/16980


	8. Electrocatalytic oxidation and voltammetric determination of tyrosine, tryptophan and their derivatives at a uracil grafted glassy carbon electrode
	Guang-feng Kang,Xiao-hong Zhu,Xiang- qin Lin
	Chemistry 22 March 2007
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	Abstract:A uracil grafted glassy carbon electrode (Ura/GCE) was fabricated. The electrode was characterized by x-ray photoelectron spectroscopy (XPS), cyclic voltammertry (CV) and differential pulse voltammetry (DPV) techniques. The electrochemical behaviors of Trp, Tyr and their derivatives, such as dopamine (DA), epinephrine (EP) and norepinephrine (NE) at Ura/GCE were investigated. All these bioactive species can be electrocatalytically oxidized at significantly reduced overpotentials and generate sensitive current signals at Ura/GCE. The linear range (detection limit, s/n=3) obtained for Tyr and Trp was 1.8 -12 0 礛 (0.8 礛) and 1.8 - 890 礛 (0.8 礛), respectively. In the coexistence of 1.0 mM AA (Ep(DPV)=-0.02 V), the linear range (detection limit, s/n=3) obtained for DA, EP, NE was 0.37 -36 礛 (0.2 礛), 0.38-13 礛 (0.2 礛), and 1.8 -84 礛 (0.8 礛), respectively. The Ura/GCE showed good electrocatalytic ability and anti-interference ability. The mechanism for Trp (Tyr) electrocatalytic oxidation was proposed.
	TO cite this article:Guang-feng Kang,Xiao-hong Zhu,Xiang- qin Lin . Electrocatalytic oxidation and voltammetric determination of tyrosine, tryptophan and their derivatives at a uracil grafted glassy carbon electrode[OL].[22 March 2007] http://en.paper.edu.cn/en_releasepaper/content/11596


	9. Platinum nanoclusters dispersed polypyrrole nanowires as electrocatalysts for fuel cells
	Li Jing,Lin Xiangqin
	Chemistry 22 March 2007
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	Abstract:The composite of polypyrrole (PPy) nanowires containing highly dispersed Pt nanoclusters was synthesized on glassy carbon electrode (GCE) utilizing cyclic voltammetry (CV) method. The electrocatalytic activities toward oxygen reduction reaction (ORR) and methanol oxidation reaction (MOR) have been investigated by CV and chronoamperometry. The PPy-Pt/GCE provided an ORR peak at about 0.52 V (vs. SCE) at 50 mV s-1. For MOR, a high ratio of forward anodic peak current to reverse anodic peak current was observed, indicating an efficient oxidation of methanol to CO2 on the PPy-Pt/GCE. The higher catalytic activity was attributed to the high dispersion of Pt nanoclusters in the larger surface area of the PPy nanowires and the synergic effect of the novel Pt core - PPy shell. The results revealed that the PPy-Pt nanocomposite was effective electrocatalyst for direct methanol fuel cells (DMFCs).
	TO cite this article:Li Jing,Lin Xiangqin. Platinum nanoclusters dispersed polypyrrole nanowires as electrocatalysts for fuel cells[OL].[22 March 2007] http://en.paper.edu.cn/en_releasepaper/content/11588


	10. IR/MS study on 3,5-dimethyladamantanamine hydrochloride salt
	Huixue Ren,Jimao Lin,Yinshan Qi,Yeqing Zhang ,Qinghe Zhang
	Chemistry 08 January 2007
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	Abstract:Infrared spectra shows that the characteristic absorptions of 3,5-Dimethyladamantanamine hydrochloride are the overtones of NH3+ deformation vibrations at frequencies of 3171.9 cm-1, 2993.8 cm-1, and the overtones involving NH3+ deformation vibration in 2600-2000 cm-1 region. The NH3+asymmetry and symmetry deformation vibrations were found at 1596.2 and 1503.5 cm-1 with a medium intense. The 1311.6 cm-1 and 1192.2 cm-1 are attributed to rocking vibration and C-N bond stretching vibration respectively. The absorption in 2850-2950 cm-1 indicate the presence of CH3, CH2 and CH groups. The ESI mass spectrum only gives three peaks but shows essential information of molecular structure. The ]M+H] ion undergoes elimination of NH3, forming m/e 163. The m/e 107 peak is produced by a simple carbon-carbon fragmentation, followed by two-step six-numbered MaLafferty rearrangements with elimination of isobutene.
	TO cite this article:Huixue Ren,Jimao Lin,Yinshan Qi, et al. IR/MS study on 3,5-dimethyladamantanamine hydrochloride salt[OL].[ 8 January 2007] http://en.paper.edu.cn/en_releasepaper/content/10604

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