最新刊期
卷 30 ， 期 5 ， 2011
- 摘要：An imprinted electrochemical sensor with specific recognition ability for L-phenylalaine was synthesized with multi layer modified zinc oxide nanofilms(ZnO-NFs),multi walled carbon nanotubes(MWNTs),copper nanoparticles(Cu-NPs) and sol-gel molecularly imprinted polymer(MIP) on the surface of carbon electrode in succession.The morphologies of the modified sensors were investigated by scanning electron microscope(SEM).The electrochemical performance and the optimal conditions for detection of L-phenylalaine were investigated by cyclic voltammetry(CV),differential pulse voltammetry(DPV),amperometric I-t curve and linear sweep voltammetry(LSV).When the scanning rate was 100 mV/s,operating voltage was 0.15 V and pH was 5.5,the calibration curve was linear over the L-phenylalaine concentration range of 5.0×10-8-2.0×10-5 mol/L with a limit of detection of 3.9×10-9 mol/L.This sensor was successfully employed to detect L-phenylalaine in human serum sample with recoveries of 98%-101%.关键词：imprinted sensor;L phenylalaine;zinc oxide nanofilms;multi walled carbon nanotubes;copper nanoparticles
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发布时间： - 摘要：The microenvironment change of macromolecular chains of pH/temperature dually responsive microgels with interpenetrating polymer network（IPN） structure,based on poly（N isopropylacrylamide） （PNIPA） network and poly（acrylic acid） （PAA） network in D2O dispersion during their phase transition,were investigated by Fourier transform infrared（FTIR） spectra and IR difference spectra at different temperatures and pH values.With the increase of pH value of D2O,the intensity of the symmetric C‖O stretch IR band from carboxylate anions（1 568 cm-1） was increased,and the intensity of the C‖O stretch band from COOH groups（1 705 cm-1） was decreased,which indicated that the COOH groups of PAA chains in the microgels dissociated into COO-leading to the phase transition induced by pH variation.However,IR bands of main characteristic peaks of PNIPA were hardly changed,which indicated the microenvironment of PNIPA chains was not evidently changed with the pH variation,and the PNIPA network within the microgels holds relative independence.The appearance of both positive peak（1 650 cm-1 and 1 448 cm-1） and negative peak（1 625 cm-1 and 1 479 cm-1） with the redshift of the amide Ⅱ bands and the blueshift of the amideⅠ bands of PNIPA component after temperature induced phase transition of the microgels exhibited that the hydrogen bonds between amide groups and waters were damaged,and the number of free amide groups were increased.In addition,the appearances of both positive peak（2 970 cm-1） and negative peak（2 990 cm-1） with redshift of the C—H stretching bands for the isopropyl groups of PNIPA component may be due to breakdown of water cage structure around the groups.关键词：Fourier transform infrared spectrum（FTIR）;poly（N-isopropylacrylamide）;poly（a crylic acid）;interpenetrating polymer network structure;microgels;phase transition
- 1995
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- 1082
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发布时间： - 摘要：A novel stationary phase for strong cation exchange chromatography was prepared by “grafting from” strategy.Atom transfer radical polymerization(ATRP) of sodium 4 vinylbenzenesulfonate(NaSS) was conducted in N,N dimethylformamide(DMF) solution at room temperature,which was synthesized by the chemical modification of 7 μm monodisperse PGMA/EDMA beads as initiator,CuCl/CuCl2/Bpy as catalyst system,under a nitrogen atmosphere with a closed system.The amounts of NaSS grafted chains with different ATRP formulations were calculated based on the elemental analysis.The effects of the NaSS grafted chain lengths on PGMA/EDMA beads for the separation of proteins,adsorption capacity,pH of mobile phase on the protein retention were investigated in details.Under the condition of catalyst∶ligand∶monomer with mole ratio of 1∶5∶100,the dynamic capacity of this packings was obtained to be 465 mg/gThe results showed that four proteins were completely separated in 10 min by linear gradient at a flow rate of 10 mL/min,and the retention time of packing increased with the increase of monomer，which was found to follow the cation exchange chromatographic(IEC) retention mechanism.关键词：atom transfer radical polymerization(ATRP);strong cation exchange chromatography;protein separation
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- 1039
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发布时间： - 摘要：A novel DNA electrochemical probe(locked nucleic acid，LNA） was designed and involved in constructing an electrochemical DNA biosensor for the detection of PML/RARα fusion gene in acute promyelocytic leukemia(APL). This biosensor was based on a “sandwich” detection strategy，which involved a pair of LNA probes，eg.hairpin capture probe and reporter probe. Streptavidin-HRP was bound to biotin labeled at the end of reporter probe via streptavidin-biotin affinity binding. In the presence of hydrogen peroxide(H2O2），HRP catalyzed the oxidation of the substrate 3,3′,5,5′ tetramethylbenzidene(TMB） to offer an enzymatically amplified electrochemical current signal for the detection of target DNA. This sensor was applied in the direct quantitative detection of synthetic PML/RARα fusion gene in PBS buffer. The results indicated that the biosensor showed an excellent specificity to distinguish the complementary sequence and different mismatch sequences. A linear relationship between the amperometric signal and the target concentration was obtained in the range of 1.0×10-11-1.6×10-10 mol/L with a detection limit of 1.0×10-13 mol/LIn addition，the biosensor was used for the determination of PML／RARα fusion gene in human serum samples without dilution with high sensitivity,selectivity and good repeatability.This method would be expected to use in real sample for further solving the actural problems of early diagnosis and prognosis monitoring of APL.关键词：electrochemical biosensors;sandwich structure;hairpin DNA probe;locked nucleic acid;PML／RARα fusion gene
- 2066
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发布时间： - 摘要：In this paper，the part base sequences of APC gene on exon 11 were extracted from normal tissue and gastric cancer tissue and amplified by polymerase chain reaction（PCR），which contains some bases easily resulting in loss of heterozygosis（LOH）.Then the amplified samples were denatured at 96 ℃ and digested by restriction enzyme of RsaⅠand detected by capillary electrophoresis（CE）-single strand conformation polymorphism（SSCP），capillary electrophoresis-restriction fragment length polymorphism（RFLP） and polyacrylamide gel electrophoresis（PAGE）-SSCP.The concentration of polyacrylamide gel was selected to be 15%.The analysis of APC gene on exon 11 was performed by CE combined with laser induced fluorescence detector（λex=488 nm，λem=520 nm），by using 3.0% polyethylene oxide（PEO） as sieving medium，1×TBE（pH 8.2） as electrophoresis buffer with a separation voltage of 15 kV at 15 ℃.The sequence of detection ratios for APC gene detected by different methods was as follows:CE-SSCP（30%）>PAGE-SSCP（25%）>CE-RFLP（20%）.The results revealed that the LOH of APC gene in gastric cancer tissue was higher than 10%，and the detection ratio for CE-SSCP was higher than that for PAGE-SSCP and CE-RFLP.Therefore，with the advantages of rapidness and high sensitivity，the CE-SSCP method could lay a good foundation for the convenient,reliable and early diagnosis on gastric cancer.关键词：gastric cancer;loss of heterozygosity;capillary electrophoresis;polyacrylamide gel electrophoresis;single strand conformation polymorphism;restriction fragment length polymorphism
- 1971
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- 904
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- 0
发布时间： - 摘要：A gas chromatography-positive chemical ionization mass spectrometric（GC-PCI/MS） method was developed for the determination of migration levels of 7 N-nitrosamines and N-nitrosatable substances including N-nitrosodimethylamine（NDMA），N-nitrosodiethylamine（NDEA），N-nitrosodi n propylamine（NDPA），N-nitrosodi n butylamine（NDBA），N-nitrosopiperidine（NPIP），N-nitrosopyrrolidine（NPYR） and N-nitrosomorpholine（NMOR） from household rubber gloves by using Sep Pak AC2 connecting to Sep Pak Dry cartridges.The developed method was simple，rapid，sensitive and accurate.Its quantitation limits for N-nitrosamines and N-nitrosatable substances were 1.25 μg/kg and 5.0 μg/kg，respectively.The total release values for the 7 N-nitrosatable substances were 6.96-168.46 μg/kg,in which NDEA，NDMA and NDBA were found most frequently in 13 analysed household rubber gloves.The risk exposure levels of seven N nitrosamines from household rubber gloves were in the class of 1.81-43.80 μg per person in a year，which would bring a potential risk to people，especailly to some occupational population.关键词：gas chromatography-positive chemical ionization mass spectrometry（GC-PCI/MS）;gloves;N nitrosamines;N-nitrosatable substances;migration level
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发布时间： - 摘要：The interaction between monoamine oxidase(MAO)and substrate Kyn was characterized by affinity capillary electrophoresis.The specific interaction between them was further demonstrated by adding an inhibitor clorgiline to MAO.The results demonstrated that the relative migration time ratio(RMTR)of Kyn decreased with the increase of MAO concentration in running buffer and the chromatographic peak of Kyn migrated far from that of triethyl benzyl ammonium chloride(TEBA) gradually.However,after adding the MAO inhibitor clorgiline,it was found that the values of RMTR of Kyn increased.This showed that the active site of MAO was occupied by clorgiline and the interaction between Kyn and MAO was inhibited.The developed method can be used to characterize the specific interaction between MAO and Kyn.Compared with the traditional methods of MAO inhibitors screening,eg.spectrophotometric assay and radiochemical analysis,the presented method could provide a potential analytical tool for the screening of MAO inhibitor with the advantages of rapidness,convenience and less sample consumption.关键词：capillary electrophoresis;interaction;monoamine oxidase;Kyn;inhibitor
- 2022
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- 979
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- 0
发布时间： - 摘要：A multi residue analytical method was developed for the determination of 185 pesticides in nuts(peanuts, sunflower seeds, walnuts and amonds) by gas chromatography tandem mass spectrometry(GC-MS/MS). The pesticide residues were extracted twice with homogenizer using acetonitrile containing 1% acetic acid. The extract was cleaned up with ENVI 18 tandem PSA solid phase extractor and analyzed by GC-MS/MS under multiple reaction monitoring(MRM) mode. The limits of detection(LOD,S/N=5) were between 0.02 μg/kg and 526.4 μg/kg, in which the LODs of 81% of the tested pesticides were lower than 10 μg/kg. The limits of quantitation(LOQs,S/N=10) of 185 pesticides were less than the maximum residue limits(MRL). All of the tested pesticides showed good linear relationship(r>0.99) between 1 and 83 times of LOQs. The four samples were determined at three spiked levels of 1, 2,4 times LOQ. The average recoveries of 86.0% pesticides were between 70% and 110%, and 90.5% pesticides were between 60% and 120%. The RSDs of 82.3% pesticides were less than 10%. This method was simple, sensitive and accurate, and could be used for the routine analysis of pesticide residues in nuts.关键词：GC-MS/MS;pesticide residues;peanuts;sunflower seeds;walnuts;almonds
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发布时间： - 摘要：A GC-MS method was developed for the determination of 16 kinds of harmful substances(eg.methanol,volatile halohydrocarbons,benzene homologues,the free toluene diisocyanate and hexane diisocyanate)in solvent based coatings.The extraction and separation efficiencies of targeted compounds by using organic solutions of ethyl acetate,n hexane,tetrahydrofuran and acetonitrile were investigated.The procedure of sample pre treatment and the conditions of instruments were optimized.The quantitative analysis of compounds were carried out by using 2-bromopropane and 1,2,4-trichlorobenzene as the internal standard,and acetonitrile as extraction reagent.The result indicated that the calibration curves of the 16 harmful substances were linear in the range of 5-200 mg/L with correlation coefficients no less than 0.999.The spiked recoveries ranged from 80% to 105% with relative standard deviations less than 5.0%.The detection limits ranged from 0.08 mg/L to 1.41 mg/L.The method was rapid,sensitive and accurate.关键词：solvent based coatings;harmful substances;GC-MS;sonicate extraction
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发布时间： - 摘要：A normal high performance liquid chromatography with UV detection was developed for the determination of phosphatidyl cholines（PC），phosphatidyl ethanolamines（PE） and phosphatidyl inositol（PI） in soybean and soybean oil samples.Effects of extraction solvent，ultrasonic power，ultrasonic time，extracting temperature and purification method on the extraction efficiency were investigated.Effects of different stationary phases on the separation efficiency were studied.The optimal extraction conditions were as follows：extraction solvent:chloroform-methanol（2∶1，by volume）；ultrasonic extraction power：1 500 W；extraction time：30 min.The purification and separation of three phospholipid compounds were performed on an amine solid phase extraction column and a silica gel column with a mobile phase of hexane-isopropanol-1% HAc solution（8∶8 ∶1，by volume）.Under the optimized conditions，the linear ranges for the PC，PE and PI were in the range of 0.08-8.00，0.15-15.00,0.30-20.00 g?L-1，respectively.The limits of quantitation for the PC，PE and PI were 0.021，0.050,0.060 g?L-1，respectively,and the limits of detection were in the range of 8-23 mg?L-1.The recoveries of three phospholipids in fortified soybean and soybean oil sample ranged from 85% to 108%.The intra day RSDs and inter day RSDs of three phospholipid compounds were no more than 4.7% and 8.6%，respectively.关键词：normal phase HPLC;soybean;soybean oil;ultrasonic extraction;phospholipid
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发布时间： - 摘要：The interaction between baicalin and human serum albumin（HSA） was investigated by fluorescence spectroscopy,circular dichroism,UV absorption spectroscopy,Fourier transform infrared spectroscopy and molecular modeling under simulated physiological conditions. The results indicated that the binding constants at 299 K and 309 K were calculated to be 1.28×105 L?mol-1 and 0.91×105 L?mol-1,respectively. The thermodynamic parameters（the enthalpy change（ΔH）：-26.2 kJ?mol-1；the entropy change（ΔS）：10.1 J?mol-1?K-1） suggested that electrostatic interaction was the predominant force in the baicalin-HSA complex,though there was hydrophobic interaction. Molecular modeling suggested that baicalin was located in subdomain ⅡA by hydrophobic and electrostatic forces,which agreed with the results obtained by fluorescence spectroscopy.The formation of the baicalin -HSA complex did not change the secondary structure of HSA by circular dichroism and Fourier transform infrared spectroscopy. Synchronous fluorescence showed that baicalin binding to HSA had changed the microenvironment around tryptophan（Trp）with polarity increasing.关键词：baicalin;human serum albumin;spectroscopy;molecular modeling;interaction
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发布时间： - 摘要：On the basis of a chemically modified platinum electrode by europium （Ⅲ）-doped Prussian blue analogue film（Eu-PB） as a working electrode，a rapid and sensitive method for the determination of polyoxin B was established using capillary electrophoresis coupled with electrochemiluminescence detection（CE-ECL）.Parameters related to the separation and detection were discussed and optimized.The possible mechanism of ECL was briefly discussed.Under the optimized conditions（ECL detection potential at 1.27 V，electrokinetic injection for 10 s at 8.5 kV，16 kV as the separation voltage，20 mmol/L pH 8.5 phosphate buffer containing 16 % acetonitrile as running buffer），polyoxin B was separated within 4 min，and the ECL intensity was in proportion to logarithm of polyoxin B concentration over the range of 1.0×10-4-5.0×10-4 g/L and 5.0×10-4-5.0×10-2 g/L with a detection limit(3σ) of 9.2×10-5 g/L.The relative standard deviations（RSDs） of intra day and inter day ECL intensity and migration time were all less than 5.0%.The proposed method was successfully applied in the determination of polyoxin B absorbed in three kinds of soils（egbentonite，kaolinite and loess） with the recoveries of 92%-104%.The results also showed that the adsorption rate of polyoxin B in soils for 2 h was 89.0% for bentonite，45.5% for kaolinite and 40.4% for loess，respectively，indicating that the adsorption capacity of polyoxin B in different soils was bentonite>kaolinite>loess.The possible reason was related to the characteristics，specific surface area and cation exchange capacity（CEC） of soils.关键词：capillary electrophoresis;electrochemiluminescence;polyoxin B;soil
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发布时间： - 摘要：A novel gold nanoparticles（GNP） and ionic liquid ［BMIM］PF6 modified glassy carbon electrode（GNP-［BMIM］PF6/GCE） was prepared. GNP and ［BMIM］PF6 were characterized by IR spectra. The electrode surface electrochemical property of GNP-［BMIM］PF6 modified electrode was studied by electrochemical impedance spectroscopy（EIS） and the behavior of bisphenol A （BPA） on the modified elctrode was investigated by cyclic voltammetric method. The result indicated that one oxidation peak was observed on the modified electrode and no reduction peak was found,which showed that the electrochemical reaction of BPA on the electrode was an irreversible process. The oxidation peak currents were linear to v1/2 in the range of 40-280 mV?s-1,indicating that the electrode process was controlled by diffusion. The effective area and electron number of GNP- ［BMIM］PF6/GCE were calculated to be 0.338 cm2 and 2，respectively. The peak current was linear over BPA concentration in the range of 5.0×10-8-2.5×10-4 mol?L-1 with a correlation coefficient of 0.997,and the detection limit was 4.42×10-8 mol?L-1. The proposed method was successfully applied in the determination of BPA in real water samples with spiked recoveries of 99%-105%.关键词：gold nanoparticles（GNP）;ionic liquids;bisphenol A （BPA）;square wave voltammetry
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发布时间： - 摘要：One of the problems in near infrared quantitative analysis is that the calibration model built on one instrument can not be directly used on other instruments because there are many differences between a master instrument and a slave instrument.A quantitative model built on the master instrument may result in a great deviation when it was used on the slave instrument.There are many ways to solve this problem,which can be divided into two categories,eg.standard sample methods and non standard sample methods.Direct standardization（DS） algorithm is one of standard sample methods.An improvement for the direct standardization algorithm was made by a principal analysis on the data matrix generated in a slave instrument,determining the principal component number by root mean square error of prediction （RMSEP） and calculating the transfer matrix by the principal number.This number was determined by the relationship between RMSEP and the principal component number.When the RMSEP reaches a minimum,the corresponding principal component number can be used to calculate the transfer matrix.The improved method was validated by using both corn data and tobacco data.The corn data has two components,water and protein and the tobacco data has four components which are sugar,total sugar,total nitrogen and total plant akaloid.The results showed that the prediction accuracy of the corn data was improved greatly when the improved DS algorithm was used to compare with direct forecast and standard DS algorithm.The prediction accuracy of the tobacco data was relatively robust too.关键词：multivariate calibration;model transfer;direct standardization;corn;tobacco
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发布时间： - 摘要：A rapid,simple,accurate and selective synchronous fluorimetry method was developed for the determination of clebopride in human urine sample.The experiments indicated that clebopride has endogenous fluorophore,the fluorescence intensity was enhanced remarkably after adding formaldehyde.Because the emission spectra of clebopride and fluorescent substance of human urine were overlapped partially,clebopride couldnt be determined directly by the normal fluorimetric method.In order to eliminate effectively the background interference of human urine,the synchronous spectrum（Δλ=30 nm） was selected for the determination of clebopride.The experimental conditions affecting the fluorescence intensity of clebopride was optimized.Under the optimumal conditions,the fluorescence intensity was linearly proportional to the concentration of clebopride in the range of 2.8×10-5-4.0×10-3 g/L with a correlation coefficient of 0.999 9.The detection limit was 1.1×10-5 g/L.The relative standard deviation（RSD,n=11） for the determination of 4.0×10-5 g/L clebopride solution was 1.7%.The proposed method was applied in the determination of clebopride in human urine samples with recoveries of 95%-104%.关键词：clebopride;formaldehyde;urine;synchronous fluorimetry
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发布时间： - 摘要：An analytical method based on microemulsion liquid chromatography（MELC） was developed for the simultaneous determination of synephrine，evodiamine and rutecarpine in Fructus Evodiae.The samples were prepared by methanol sonication.The main factors influencing the separation selectivity，including the types and concentrations of surfactant，pH values of mobile phase and the types of organic solvent additive，were investigated.The best composition of the microemulsion system was 3.0% SDS-6.0% n butanol-0.6% n octane -1.0% formic acid -1.2% acetonitrile -88.2% water.Three target compounds were separated with Diamonsil C18 column（250 mm×4.6 mm，5 μm） at a flow rate of 0.7 mL/min.The detection wavelength was set at 260 nm.Under the optimal conditions，the calibration curves of synephrine，evodiamine and rutecarpine were linear in the range of 5.21-26.05，7.04-35.2，1.31-6.55 mg/L，respectively，with their correlation coefficients more than 0.999 7.The average recoveries of three components were between 96% and 101% with RSD（n=6） of 1.0%-1.5%.The limits of detection ranged from 0.048 to 0.095 mg/L.This method was simple，accurate and reliable，and could be applied in the determination of three components in Fructus Evodiae.关键词：microemulsion liquid chromatography（MELC）;Fructus Evodiae;synephrine;evodiamine;rutecarpine
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发布时间： - 摘要：A new flow injection analysis（FIA） system with a flat pH electrode was established for the rapid determination of acetic acid in vinegar.The FIA system was optimized by alteration of injection volume，flow rate，carrier concentration and length of reaction tubes.With sodium hydroxide solution as carrier stream，the peak area obtained from the lab assembled FIA system were proportional to the logarithm concentration of acetic acid in the range of 4639×10-4-0212 mol?L-1.The method was applied in the detection of acetic acid in four vinegar samples，and the results obtained were in good agreement with those obtained by the standard manual titration method.The sensitivity of this method was ten times higher than that of the conventional titration method，and the analysis rate was up to 60 samples per hour.By changing the concentration of carrier stream（sodium hydroxide），the acetic acids at different concentration levels can be titrated without any other adjustments to the FIA system.关键词：pH electrode;flow injection analysis;titration;acetic acid
- 2031
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- 941
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- 0
发布时间： - 摘要：A method was developed for the determination of benzo［α］ pyrene in vegetables by reformed QuEChERS and high performance liquid chromatography with fluorescence detector. The samples were extracted with acetonitrile，distilled with PSA+neutral Al2O3 column，and rinsed with mixture of hexane and acetonitrile（95∶5，by volume）. The external standard method was used to determine the content of benzo［α］ pyrene. The result indicated that the calibration curve was linear in the range of 1.0-20.0 μg/kg with correlation coefficient of 0.999.The limit of quantitation（LOQ） was 1.0 μg/kg.The recoveries of benzo［α］ pyrene were in the range of 65%-98% with RSDs of 5.9%-13.8%.The method was applied in the practical inspection on vegetables,and benzo［α］pyrene was detected in one sample with residual concentration of 1.23 μg/kg.关键词：QuEChERS;liquid chromatography-fluorescent detection;benzo［α］ pyrene;vegetables
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发布时间： - 摘要：A gas chromatography-tandem mass spectrometric(GC-MS/MS) method was established for the determination of 11 dinitroaniline herbicide in grains products.The samples were extracted with acetonitrile,and cleaned up by the QuEChERS method.A rapid analysis was carried out by GC-MS/MS under multiple reaction monitoring(MRM) mode.The external standard was used for quantitative analysis.Under the optimal conditions,the calibration curves for the 11 dinitroaniline herbicides were linear in the range of 1.0-20.0 μg/L with correlation coefficients more than 0.996.The quantitation limit of the method was 5 μg/kg.The mean recoveries for rice,soybean and wheat samples at three spiked concentrations levels of 5,10,20 μg/kg were in the range of 65%-110% with relative standard deviations(RSDs,n=7) of 2.6%-10.2%.关键词：dinitroaniline herbicide;gas chromatography-tandem mass spectrometry (GC-MS/MS);grains;determination
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- 978
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- 6
发布时间： - 摘要：FTIR was applied in the analysis of Lapis Micae Aureu samples,and the corresponding spectra were interpreted. The results indicated that the absorption characteristics of spectra of Lapis Micae Aureu samples were similar to those of the layered silicate minerals.The absorption area was divided into four regions：OH stretching vibration absorption at 3 700-3 000 cm-1,H2O bending vibration absorption at 1 620 cm-1,Si—O stretching vibration absorption at 1 000 cm-1 and Si—O bending vibration absorption at 550-400 cm-1.The results showed that,OH vibration absorption intensity was in positive proportion to water content in Lapis Micae Aureu samples and the absorption frequency was related to the type of the interlayer cation.Si—O vibration absorption frequency was affected by Al substituting Si in tetrahedroid,and the absorption frequency reflects the type of cation in octahedron.Thus the infrared spectral characteristics of Lapis Micae Aureu samples could reflect its internal structure,and could be used to evaluate its quality status.关键词：Lapis Micae Aureus;FTIR;mineral medicine
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- 907
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发布时间： - 摘要：With the accomplishment of the gene sequencing of Human Genomic Project(HGP）,increasing attention is focusing on proteomic research.Glycosylation of proteins is the most common and important post translational modification,which is composed of many covalent forms of polypeptide and oligosaccharide.The structure of sugar chain plays a crucial role in various biological processes.However,due to the existence of high abundant non glycoproteins,the low abundant glycoproteins were prone to be embedded and covered by nonglycoproteins and thus causing serious interference in further identification.The existing technologies are difficult to isolate and detect low abundant glycoproteins from complex matrices,which has become the one of the major bottlenecks currently encountered in glycoproteomics.Monolithic column,as an integrated continuous porous stationary phase,was prepared by in situ polymerization or sol-gel process inside the capillary,which can be taken as an alternative approach for isolation and enrichment of glycoproteins due to the merits of simple preparation procedure,high porosity,high capacity and high efficient separation.In this paper,the principle,preparation and classification of monolithic columns were briefly introduced.The recent advances of monolithic columns in selective separation and enrichment of glycoproteins were summarized,which included lectin based affinity monoliths,boronate affinity monoliths and immobilized metal affinity monoliths.In addition,the prospect of monolithic column for enrichment of glycoproteins was also presented.Totally,65 references were reviewed.关键词：monolithic column;glycoprotein;review
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发布时间： - 摘要：Water vapor absorption bands may severely obscure important sample features in the infrared spectrum.In order to solve this problem,many methods,such as,vacuum,dry air purging technique,sample shuttle technique and spectral subtraction,etc,have been proposed and conducted.In this article,humidity titration method to remove water vapor noise completely was emphatically reviewed.The scanning procedure of a sample single beam spectrum was divided into two stages.At the first stage,the appearance of water vapor peaks was allowed and the absorption direction（for example absorbance A≥0 or A≤0） of water vapor bands was observed easily at the end of this stage.Then,the relative humidity in the sample compartment of spectrometer was changed by a dry or a wet air supply depending on the absorption direction of water vapor bands.After the relative humidity was changed to a certain extent,water vapor peaks would become smaller and smaller with the increase in scanning number during the second stage.By this way,water vapor noise could be eliminated progressively and completely at last.关键词：infrared spectroscopy;water vapor noise;humidity titration;review
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