1.Micro Potentiometric Label-free Immunosensor for Glycated Hemoglobin
Chao BIAN ; Qiannan XUE ; Jizhou SUN ; Hong ZHANG ; Shanhong XIA
Chinese Journal of Analytical Chemistry 2010;38(3):332-336
A miniaturized potentiometric label-free immunosensor based on the standard complementary metal-oxide-semiconduction transistor(CMOS) process and micro fabrication technique was developed to monitoring diabetes, which could detect the concentrations of glycated hemoglobin (HbA1c) and hemoglobin. This immunosensor includes a micro field-effect transistor based sensor chip integrated with signal readout circuit and a disposable probe electrode. The micro sensor chip was designed by our lab and fabricated by Chartered Semiconductor, Singapore. The disposable probe electrode, which was integrated with sensitive electrodes array and micro reaction pool, was deposited on polyester plastic based on micro fabrication techniques. Antibody of HbA1c and hemoglobin were immobilized on the electrode based on self assemble monolayer and gold nanoparticles. The characteristics of the electrode during modification were studied by cyclic voltammetry and electrochemical impedance technique. The response characteristic of the immunosensor was detected. HbA1c from 4 to 24 mg/L and hemoglobin from 60 to 180 mg/L can be detected by this immunosensor.
2.Analysis of Differentially Expressed Proteome in Urinary Exosome from Non-small Cell lung Cancer Patients
Yi DAI ; Yuan ZHANG ; Feng QIU ; Yanyan LI ; Zongyin QIU
Chinese Journal of Analytical Chemistry 2010;38(3):325-331
Urine provides an alternative to blood plasma as a potential source of disease biomarkers. Exosomes was separated by ultracentrifuge at 200000 g in normal persons and non-small cell lung cancer (NSCLC) patients′ urine. For proteomic analysis of urinary exosome, 1D sodium dodecylsulfonate-polyacrylate gel electrophoresis(SDS-PAGE) was carries out and cut the gel 31 kDa-20 kDa bands in normal group and disease group′s. These gel blocks were subjected to in-gel trypsinization, and the extracted peptides were analyzed HPLC-CHIP-MS/MS. Approximately 24 unique proteins were identified in the UniProtKB/SWISS-PORT. The difference expression proteins were found in urinary exosome from NSCLC patients, including three fragment of the immunoglobulin kappa, two kinds of Ras related proteins, glutathione S-transferase A2, serum amyloid P-component precursor and phosphatidylethanolamine-binding protein 1.
3.Preparation and Certification of Reference Materials for 3-Amino-2-oxazolidinone Residue in Eel Muscle Lyophilisates
Fang YANG ; Shoushen YANG ; Shengyu LU ; Zhengcai LIU ; Kongjie YU ; Yaoping LI ; Xiaogang CHU
Chinese Journal of Analytical Chemistry 2010;38(3):397-400
A methodology for preparing and certifying the reference material of 3-amino-2-oxazolidinone(AOZ) in eel muscle lyophilisates was presented. Furazolidone was accessed to eel by dipping fish in pond with furazolidone solution at a dosage of ca 0.16 mg/L. With the metabolism of furazolidone in eel, the muscles contain a certain concentration of AOZ as furazolidone metabolite was obtained. Lyophilization of the muscles was performed in one batch and 400 bags of samples were obtained by the procedure of homogenation, cryodesiccation and irradiation. The homogeneity and stability of the sample was examined. The value of the chemical constituent of the sample was certified through the collaborative analysis program participated by 11 laboratories using isotope dilution liquid chromatography-tandem mass spectrometry, and the uncertainty assessment was performed. The reference materials have been approved as certified reference materials by AQSIQ, China (State General Administration of the People′s Republic of China for Quality Supervision and Inspection and Quarantine) in 2009 after one year of trial period. The serial numbers is GBW(E)100180.
4.Establishment of Atmosphere Pressure-Temperature Programmed Pyrolysis-Mass Spectrometric System and Its Application on Decarboxylation of Coal
Zhiqing WANG ; Zongqing BAI ; Wen LI ; Haokan CHEN
Chinese Journal of Analytical Chemistry 2010;38(3):393-396
A quartz tube reactor was designed to combine with a commercial mass spectrometer for on-line detecting the gases evolved during pyrolysis of coal and other samples with high volatile. The reliability and repeatability of this atmosphere pressure-temperature programmed pyrolysis-mass spectrum (AP-TPP-MS) system were tested by model compound and real coal sample. The results show that pyrolysis of model compound can give good response, less overlap or tailing gases evolution curves;and multi-peaks can be observed from the same gas curve of real sample. The reliability and repeatability of this system are perfect and the system can be applied to study the coals decarboxylation by comparing the CO_2 evolution curves.
5.Determination of Carbon Monoxide in Seawater by Headspace Analysis
Xiaolan LU ; Guipeng YANG ; Xiaomeng WANG ; Weilei WANG ; Chunyan REN
Chinese Journal of Analytical Chemistry 2010;38(3):352-356
Oceanic carbon monoxide(CO) has been of biogeochemical interest due to its significant role in global carbon cycle and the greenhouse effect. A headspace method coupled with ta3000 trace gas analyzer system for the determination of CO in seawater was developed. The effects of temperature, equilibrium time and water/gas volume ratio on the sensitivity of headspace analysis were studied in detail. The results showed that CO concentrations in seawater were measured successfully by the 50-mL glass-only syringes with a water/gas volume ratio of 44∶ 6 and an equilibrium time of 5 min at 20 ℃ room temperature. Under the optimized conditions, the linear range of concentrations of CO was 0-2.7×10~(-6), r=0.999,p<0.0001. The relative standard deviation of the analysis method was <4.4%, with a detection limit of 0.02 nmol/L. The average recovery of CO was 90.5%. The concentrations of CO in surface waters of the North Yellow Sea were measured using this method and ranged from 0.20 nmol/L to 3.13 nmol/L, indicating that this method can be successfully applied to the detection of the in situ CO concentrations in seawater.
6.Study of Dimethyl Carbonate Adsorption and Activation on Solid Bases by Fourier Transform Infrared Spectroscopy
Gongde WU ; Xiaoli WANG ; Qingnian DONG ; Wei WEI ; Yuhan SUN ; Shan NI ; Xinxin ZHOU
Chinese Journal of Analytical Chemistry 2010;38(3):405-408
The adsorption and activation of dimethyl carbonate on the surface of solid base were investigated by in situ FTIR, and the solid bases included magnesia, magnesium fluoride, Mg-Al mixed oxide and fluorine-modified Mg-Al mixed oxide. The FTIR results showed that dimethyl carbonate adsorbed on the surface of solid based by two modes of bidentate and unidentate complex. The bidentate was more active than the unidentate. Methoxyl group was formed from the adsorbed dimethyl carbonate on the surface of magnesia and Mg-Al mixed oxide. And fluomethyl group was formed from the adsorbed dimethyl carbonate on the surface of sodium fluoride. However, dimethyl carbonate on the surface of fluorine-modified Mg-Al mixed oxide showed preference for generating fluomethyl group. With the increasing of the treating temperature of samples, the methoxyl group was gradually formed on the surface. Accordingly, the fluorine-modified Mg-Al mixed oxide was found to be an excellent catalyst for methylation.
7.Preparation of Benzonic Acid Molecularly Imprinted Polymers and Its Adsorption Property
Dawei LOU ; Yingjie YANG ; Guang HUANG ; Pingli PU ; Xinqing LEE ; Bo ZHU ; Yuehong WANG
Chinese Journal of Analytical Chemistry 2010;38(3):401-404
A molecularly imprinted polymer (MIP) using benzoic acid as template molecule, 4-vinyl pyridine (4-VP) as functional monomer, ethylene dimethacrylate (EDMA) as cross-linker, was prepared by bulk polymerization. The needle-type gas concentrator was developed using the MIP as adsorption medium. The device was coupled with gas chromatography (GC) for the analysis of volatile organic compounds (VOCs). The effect of polymerization conditions on adsorption property, such as polymerization time, ratio of the reagents, pre-polymerization time, type of solvents, type of template molecules, has been evaluated. The results of gas chromatographic analysis demonstrated that the optimum conditions for getting the best adsorption performance of the synthesized were polymerization time 6 h at 60 ℃, the ratio of the reagents (template molecule : functional monomer : cross-linker) 1∶ 4∶ 20, pre-polymerization time of 3 h, acetonitrile as solvent, benzoic acid as template.
8.Three Electrodes Biosensor for Alcohol in Whole Blood Based on Multi-wall Carbon-nanotube
Shenghang ZHEN ; Jun ZHENG ; Chaoshi ZOU ; Yan WANG ; Yang ZHU ; Shixiong DENG ; Guoming XIE ; Jian WANG
Chinese Journal of Analytical Chemistry 2010;38(3):389-392
A novel disposable three electrodes blood alcohol biosensor strip was fabricated by a screen printing technique. Multi-wall carbon nanotube(MWCNT), Meldola′s(MB), alcohol dehydrogenase(ADH)and nicotinamide adenine dinucleotide cofactor (NAD+) were modified on the surface of the carbon working electrode. Then hydrophilic membrane was stuck in the outermost of the three electrodes to make a reaction camera of 5 μL. Experimental results indicated that the biosensor possessed good accuracy and stability, the linear response range was 0.5-20 mmol/L with correlation coefficient of 0.9949, detection limit was 0.22 mmol/L, and the response time was less than 15 s. Some influencing factors to the biosensor were investigated, such as the pH, temperature and interferences. Correlation analysis showed that there was a significant correlation between the methods of biosensor and the headspace vapor phase chromatography in 10 whole blood samples(r=0.97583). Small volume whole blood sucked using siphonage to detect blood alcohol directly and quantitatively was the obvious character of the biosensor.
9.Determination of Terbutaline Sulfate and Its Combination with β_2 Adrenergic Receptor in Erythrocyte Membrane by High Performance Liquid Chromatography
Chinese Journal of Analytical Chemistry 2010;38(3):377-380
A high performance liquid chromatographic method with hypersil C_(18) column, 0.020 mol/L potassium dihydrogen phosphate solution(which contains 0.25% triethylamine, pH 5.1)-methanol(20∶ 80, V/V) as mobile phase and fluorescence detection with 280 nm as excitation wavelength and 320 nm as emission wavelength has been developed for the determination of terbutaline sulfate and propranolol hydrochloride in Erythrocyte suspensions. Erythrocyte surface receptor oscillating reacted 1 h with terbutaline in 37 ℃ water bath. Free terbutaline and propranolol were separated from the membrane receptor-binding complex through 1500 r/min centrifugal in 5 min. The linear range was 0.010-3.000 mg/L in Alsever's solutions and the correlation coefficients were 0.9999 and 0.9998. The relative standard deviations(RSDs) of terbutaline and propranolol were 0.8% and 1.2%, respectively. The limits of detection(LODs) of both were 1.00 and 3.00 mg/L. This simple, safety and sensitive method was suitable for the determination of terbutaline and propranolol in erythrocyte suspensions and for the study of receptor-ligand binding.
10.Analysis of Structural Characteristics of Polysaccharide from Ganoderma Lucidum
Jinzhe HE ; Ping SHAO ; Xianghe MEN ; Peilong SUN
Chinese Journal of Analytical Chemistry 2010;38(3):372-376
Polysaccharide was extracted by boiling water reflux method from the fruiting body of Ganoderma lucidum. Additionally, the purified polysaccharide was obtained by removing protein with Sevage way, ethanol precipitation, centrifugation, run water dialysis, membrane separation, concentration and frozen-drying. The structural characteristics, chain conformation and triple-helix conformation of ganoderma lucidum polysaccharide (GLP) were distinguished by Smith degradation, methylation analysis, and the wavelength change of the red shift of the mixture of polysaccharide and Congo red in alkaline solution, as well as IR, GC-MS, NMR, and visible spectrometry. The results indicated that GLP was a linear (1→3) β-D-Glcp main chain linkage. Its monosaccharide component was predominantly composed of D-Glc, and small amount of galactose, mannose, xylose and idose, residues of branches terminated with substituted at 1→6 by a small number of single-unit β-D-Glcp side-chains, it′s also observed that the (1→3)-linked β-D- glucan contained a triple-helical conformation, which was composed of a repeating unit with a structure as below:→3)-β-D-Glcp-(1→3)-[β-D-Glcp-(1→3)-]_n-β-D-Glcp-(1→.↑6/1β-D-Glcp