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    Chinese Journal of Chromatography
    2013, Vol. 31, No. 1
    Online: 28 January 2013

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    Trend in proteomics analysis of phosphorylation and glycosylation
    YE Mingliang
    2013, 31 (1):  1-3.  DOI: 10.3724/SP.J.1123.2013.01001
    Abstract ( 993 )   [Full Text(HTML)] () PDF (2032KB) ( 442 )  
    Applications of multi-micro-volume pressure-assisted derivatization reaction device for analysis of polar heterocyclic aromatic amines by gas chromatography-mass spectrometry
    WANG Yiru1, CHEN Fangxiang1, SHI Yamei2, TAN Connieal1, CHEN Xi1*
    2013, 31 (1):  4-9.  DOI: 10.3724/SP.J.1123.2012.09011
    Abstract ( 1406 )   [Full Text(HTML)] () PDF (1685KB) ( 217 )  
    A multi-micro-volume pressure-assisted derivatization reaction device has been designed and made for the silylation derivatization of polar heterocyclic aromatic amines by N-(tert-butyldimethylsilyl)-N-methyl-trifluoroacetamide (MTBSTFA) with 1% catalyst tert-butyldimethylchlorosilane (TBDMCS) at a high temperature. The tert-butyldimethylsilyl derivatives then could be automatically analyzed by gas chromatography-mass spectrometry. Using the pressure-assisted device, the silylation reaction may occur at a temperature higher than the boiling points of the reagents, and several micro-volume samples can be simultaneously pretreated in the same device to shorten the sample-preparation time and to improve the repeatability. The derivatization conditions including the headspace volume of the vial, the evaporative surface area of the reagent, derivatization temperature and time have been discussed for the use of the pressure-assisted device. The experimental results proved that the device is an effective way for the simultaneous derivatization of several micro-volume samples at a high temperature. Compared with a common device, the derivative amounts were obviously increased when using the pressure-assisted device at 90 ℃. Quantitative derivatization can be achieved even at 150 ℃ while there was no common device could be applied at such a high temperature due to the heavy losses of reagents by evaporation. However, no obviously higher reaction speed has been observed in such a circumstance with a higher temperature and a higher pressure using the pressure-assisted device.
    Reviews
    Application of molecularly imprinted polymer particles in capillary electrochromatography
    YUE Chunyue1, DING Guosheng2, TANG Anna1*
    2013, 31 (1):  10-14.  DOI: 10.3724/SP.J.1123.2012.08007
    Abstract ( 1576 )   [Full Text(HTML)] () PDF (889KB) ( 223 )  
    Molecularly imprinted polymer (MIP) particles prepared by molecular imprinting technique (MIT) possess the ability of specific identification and selective affinity towards template molecules and their structural analogues. They also have a large specific surface area and rapid mass transfer kinetics, thus they have been widely used as stationary phases in liquid chromatography and matrixes in solid phase extraction. Using MIP particles as capillary electrochromatography (CEC) stationary phase, which combines the high speed and efficiency of CEC with the high affinity and selectivity of MIP, has become one of the most promising separation technique in analytical science. There are several different strategies of MIP particles applied in CEC: as packing materials packed into a capillary column; as entrapping materials entrapped into different matrix frameworks inside a capillary column; as pseudostationary phases (PSPs) added into the running buffer of CEC. This review focuses on the recent developments of MIP particles in CEC and prospects the future developments in this field.
    Articles
    Simultaneous determination of 18 pharmaceuticals and personal care products in surface water by ultra-high performance liquid chromatography-tandem mass spectrometry
    ZHU Saichang1, WANG Jing2, SHAO Weiwei2, CHEN Hong1*
    2013, 31 (1):  15-21.  DOI: 10.3724/SP.J.1123.2012.09015
    Abstract ( 1646 )   [Full Text(HTML)] () PDF (978KB) ( 361 )  
    An analytical method has been developed and validated for the simultaneous determination of 18 pharmaceuticals and personal care products (PPCPs), including antibiotics (trimethoprim, erythromycin•2H2O, norfloxacin, ofloxacin, pencilline G, penicillin V potassium salt, cephalexin and sulfamethoxazole), β-bloker (atenolol), anophelifuge (N,N-diethyl-3-methylbenzoylamide, DEET), antiepileptics (carbamazepine), central nervous system stimulant (caffeine), lipid modifying agent (clofibric acid), non-steroidal anti-inflammatory drugs (ibuprofen, naproxen and diclofenac sodium salt) and antimicrobial agents (triclosan and triclocarban). The detection and qualification of the target compounds were performed by ultra-high performance liquid chromatography-tandem mass spectrometry. The optimized mobile phases were methanol as organic phase, 0.3% (v/v) formic acid-5 mmol/L ammonium acetate for positive electrospray ionization (ESI+) and 5 mmol/L ammonium acetate for ESI- as inorganic phase. Water samples were concentrated by solid phase extraction at 2 mL/min, and all the target PPCPs were efficiently extracted at pH 7. The extracted PPCPs were eluted by the mixture of methanol and acetonitrile (1:1, v/v). The average recoveries of the target compounds in the spiked pure water samples ranged from 53.9%-112%. The average recoveries of the target compounds ranged from 45.1%-156.6% with the relative standard deviations ranged from 2.4%-15.7%, in the surface water samples spiked at 100 ng/L. The surface water samples collected from Yu Hangtang River in Hangzhou were detected. The results showed that nine PPCPs were detected including caffeine that reached a maximum concentration of 550.7 ng/L. It proved that this analytical method is reliable and acceptable.
    Determination of four kinds of illegal additive residues in sprouts and source beans by high performance liquid chromatography-tandem mass spectrometry
    LIU Han*, WU Bin, YIN Yao, XU Wei, GUI Qianwen, YU Keyao, GONG Yuxia, ZHAO Zengyun, LIN Hong, SHEN Weijian, SHEN Chongyu, ZHANG Rui
    2013, 31 (1):  22-26.  DOI: 10.3724/SP.J.1123.2012.07039
    Abstract ( 1322 )   [Full Text(HTML)] () PDF (806KB) ( 339 )  
    A reversed-phase high performance liquid chromatography coupled with tandem mass spectrometric (LC-MS/MS) method was developed for the determination of 4-chlorophenoxyacetic acid, 6-benzylaminopurine, enrofloxacin and norfloxacin residues in sprouts and source beans. The sample was extracted by acetonitrile containing 0.1% acetic acid and concentrated. The chromatographic analysis was carried out on a C18 column with methanol and 0.1% formic acid solution as the mobile phases in gradient elution program. The MS analysis was set in electrospray ionization mode and separated to two segments of positive and negative modes. The precursor ions were m/z 189.9, 226.1, 359.9 and 320.1, while the product ions for quantification were m/z 127.0, 91.2, 315.9 and 276.2 for 4-chlorophenoxyacetic acid, 6-benzylaminopurine, enrofloxacin and norfloxacin, respectively. The calibration curves showed good linearity in the range of 5-200 μg/L with correlation coefficients more than 0.995. The limits of detection (LODs) were 1 μg/kg and the limits of quantification (LOQs) were 5 μg/kg for the four compounds spiked in mung bean sprouts and mung beans. The recoveries of the four compounds spiked at three levels of 5.0, 10.0 and 20.0 μg/kg ranged from 70% to 91%, with the relative standard deviations (RSDs) less than 14%. The method established is accurate, sensitive, simple, and has considerable advantages in the analysis of the four kinds of illegal additive residues in sprouts and beans simultaneously.
    Determination of inabenfide residue in food by high performance liquid chromatography-tandem mass spectrometry
    XU Meiling1, CUI Shuhua2*, LIU Tongying1, QIAN Jialiang1, ZHANG Lidong1, DUAN Hao1, LIU Bing1
    2013, 31 (1):  27-32.  DOI: 10.3724/SP.J.1123.2012.08009
    Abstract ( 1301 )   [Full Text(HTML)] () PDF (885KB) ( 237 )  
    A high performance liquid chromatography-tandem mass spectrometry (HPLC-MS/MS) method was established for the determination of inabenfide in fruits, vegetables, tea, honey, cereals and animal-derived foods. The food samples were extracted with acetonitrile, then purified by dispersion solid phase extraction using primary secondary amine (PSA) and C18 as solid phase. The residue was determined and confirmed by HPLC-MS/MS and quantified by external standard method. The mass spectrometric detection was operated with electrospray in positive ionization mode and inabenfide was identified in multiple reaction monitoring (MRM) mode. The interference of matrix was reduced by the matrix-matched calibration standard curves. The linear range of the method was 1-100 μg/kg, with the correlation coefficients (r2) of 0.998-0.999. The recoveries of inabenfide spiked in food samples were 85.2%-112.4% at the spiked levels of 5, 10, 50 μg/kg. The relative standard deviations (RSDs) were less than 8.5%. The limits of detection (LODs) were 0.08-1.64 μg/kg, and the limits of quantification (LOQs) were 0.30-5.48 μg/kg. The results showed that the proposed method is sensitive and accurate for the determination of inabenfide in foodstuffs.
    Determination of acetyl coenzyme A in grape berries by high performance liquid chromatography-tandem mass spectrometry
    YANG Yan, WU Guangfeng*
    2013, 31 (1):  33-37.  DOI: 10.3724/SP.J.1123.2012.09004
    Abstract ( 1520 )   [Full Text(HTML)] () PDF (1084KB) ( 380 )  
    A high performance liquid chromatography-tandem mass spectrometry (HPLC-MS/MS) method was developed for the determination of acetyl coenzyme A in grape berries using n-propionyl coenzyme A as an internal standard (IS). The sample was extracted with water and then centrifuged for 5 min at 10000 r/min on a centrifuge at 4 ℃, and cleaned-up with a C18 solid phase extraction cartridge. The identification and quantification were carried out by using electrospray ionization in positive ion mode (ESI+) with multiple reaction monitoring (MRM). The total run time was 1 min and the elution of both acetyl coenzyme A and n-propionyl coenzyme A occurred at about 0.45 min. This was achieved with a mobile phase consisting of 5 mmol/L ammonium formate-acetonitrile (20:80, v/v) at a flow rate of 0.4 mL/min on a C18 column. A linear response function was established for the concentration range of 1-2000 μg/L for acetyl coenzyme A and the correlation coefficient was more than 0.99. The limit of detection of acetyl coenzyme A was 0.1 μg/L. The spiked recoveries at 50, 500, 1000 μg/L ranged from 82.87%-89.67% with the relative standard deviations less than 10%. This method is simple, rapid, sensitive and can significantly reduce the loss of acetyl coenzyme A during the experiment. It is suitable for the determination of acetyl coenzyme A in grape berries.
    Rapid analysis of 28 primary aromatic amines in aqueous food simulants by high performance liquid chromatography-tandem mass spectrometry
    XIAO Xiaofeng, WANG Jianling*, YANG Juanjuan, LIU Tingfei, CHEN Tong, HE Jun, DENG Hongyi, GAO Qiyan
    2013, 31 (1):  38-45.  DOI: 10.3724/SP.J.1123.2012.10028
    Abstract ( 1938 )   [Full Text(HTML)] () PDF (1220KB) ( 257 )  
    A novel method for rapid analysis of the migration amounts of 28 primary aromatic amines (PAAs) in aqueous food simulants (10% ethanol, 30 g/L acetic acid and 20% ethanol aqueous solution) was developed using high performance liquid chromatography-tandem mass spectrometry (HPLC-MS/MS). After the migration test, the soaking solution was cooled down from 100 ℃, vortexed, filtered through a hydrophilic polytetrafluoroethylene filter with a disposable syringe, and then the filtrate was analyzed by HPLC-MS/MS. A Zorbax SB-Phenyl column (250 mm×4.6 mm, 5 μm) was selected for chromatography. The mobile phase consisted of water and 0.1% formic acid-25% acetonitrile-methanol solution with gradient elution. The 28 PAAs in aqueous food simulants were detected by tandem mass spectrometer operated in positive electrospray ionization (ESI+)and multiple reaction monitoring (MRM) mode. The limits of quantification for the 28 PAAs were between 0.002 μg/L and 10 μg/L. The linearity of the method was good with correlation coefficients (r2) greater than 0.995 over the concentration range from 5 μg/L or 10 μg/L to 100 μg/L. The average recoveries of the 28 PAAs were between 76.6% and 114% with the relative standard deviations between 1.53% and 8.97% at the levels of 10, 20, and 40 μg/L. The method shows rapid pretreatment, the lower limits of quantification, good recoveries and accuracies, and meets the requirement of European Union (EU)No 10/2011 regulation for the specific migration of PAAs. The method has been applied to analyze the 28 PAAs in different aqueous food simulants from the migration test of 30 batches of food contact material samples exported to EU.
    Determination of migration of 25 primary aromatic amines from food contact plastic materials by gas chromatography-mass spectrometry
    LI Ying1*, LI Chengfa1, XIAO Daoqing2, LIANG Feng1, CHEN Zhinan1, CHEN Xuhui1, SUN Xiaoying1, LI Yongtao1
    2013, 31 (1):  46-52.  DOI: 10.3724/SP.J.1123.2012.08055
    Abstract ( 2330 )   [Full Text(HTML)] () PDF (2520KB) ( 503 )  
    A solid phase extraction (SPE) combination with gas chromatography-mass spectrometry (GC-MS) was developed for the determination of the migration of 25 primary aromatic amines (PAAs) from food contact plastic materials and articles. The samples were extracted by deionized water and 30 g/L acetic acid, and the pH value of the solution was adjusted to 8-10 with ammonia. The extracts were cleaned up and concentrated on an SPE column, then eluted by equal volume of methyl-tert-butyl ether and ethanol. The analysis of the target compounds was performed by GC-MS. The results indicated that the limits of detection were in the range of 0.4-2.0 μg/kg for different PAAs. The recoveries and relative standard deviations (n=7) of 10 μg/kg PAAs ranged from 51.6%-118.4% and 0.5%-9.8%, respectively, except the 2,4-diaminoanisole in the acid simulant. The effects of different experimental conditions such as the pH value and volume ratio of methyl-tert-butyl ether and ethanol were studied. The results showed that the method is accurate and stable, and could meet the requirement of the European Commission Regulation (EU) No 10/2011 for the determination of primary aromatic amines. It can be applied in the analysis of the primary aromatic amines in real food contact plastic material and article samples.
    Simultaneous determination of neutral sugars and uronic acid constituents in a novel bacterial polysaccharide using gas chromatography-mass spectrometry
    WANG Fengqin, YANG Hangxian, WANG Yizhen*
    2013, 31 (1):  53-58.  DOI: 10.3724/SP.J.1123.2012.08013
    Abstract ( 1878 )   [Full Text(HTML)] () PDF (1512KB) ( 349 )  
    The purified novel bacterial polysaccharide was acid-hydrolyzed, followed by the subsequent derivatization using ethanethiol-trifluoroacetic acid and acetic anhydride-pyridine systems sequentially. Our findings differ from the previous reports in that the glucuronic acid was obtained through effective derivatization. The neutral sugars and glucuronic acid were analyzed using gas chromatography-mass spectrometry (GC-MS) with xylose as an internal standard. The polysaccharide was found to be composed of fucose, glucose, glucuronic acid and galactose, with the relative molar ratio of 1.50:1.0:0.79:2.06. The neutral sugars ratio was similar to the relative molar ratio for fucose, glucose and galactose of 1.76:1.0:1.98 through alditol acetates determined by GC. The percentages of glucuronic acid analyzed using either the carbazole and sulfuric acid method or the above method were 16.19% and 14.85%, respectively. These results indicate that it is practicable to use the derivatization method and GC-MS to quantitatively analyze neutral sugars and glucuronic acid simultaneously in polysaccharide. For GC-MS analysis, the procedure was developed for the simultaneous determination of the derivatives in 25 min, and was performed using an HP-5MS column. Molecular ion peaks were observed in the electron ionization (EI) mass spectra. The fragmentation mechanism for glucuronic acid derivative is discussed in detail.
    Application of capillary zone electrophoresis in the interaction analysis of protein C with protein C activator from Agkistrodon acutus venom
    SUN Yao1,2, BAO Pengju3, ZHANG Genbao1,2*
    2013, 31 (1):  59-63.  DOI: 10.3724/SP.J.1123.2012.07041
    Abstract ( 1124 )   [Full Text(HTML)] () PDF (970KB) ( 189 )  
    A new capillary zone electrophoresis method (CZE) has been established for the interaction analysis of protein C (PC) with a protein C activator (PCA) from Agkistrodon acutus venom. The analysis was performed on an uncoated fused-silica capillary with 75 μm i.d. and a total length of 60.2 cm (50 cm to the detector) with a buffer solution of 50 mmol/L Tris-HCl (pH 7.4) and 198 nm of wavelength. The factors which influence the separation of the PCA, such as buffer solution and ion concentration, and the interaction between the PCA and PC incubated for different times at 37.5 ℃ were studied. The linear range was from 10 to 300 mg/L. The limit of detection was 3 mg/L (S/N=3). The relative standard deviation (RSD) for the migration time of the PCA was 0.56%. The RSD for the peak area was 3.8% (n=6). The equal volumes of the PCA (200 mg/L) and PC (60 mg/L) were incubated for five minutes, at which their binding rate reached the maximum. And no hydrolyzed peptide chain from PC was found in the electropherogram. The PCA from Agkistrodon acutus venom could activate PC directly through changing the space conformation of PC. The method is simple, and highly sensitive with high resolution, and will provide important theoretical basis for the rapid detection of venom proteins and their activities in the future.
    Simultaneous determination of o-phthalaldehyde, p-chloro-m-xylenol and triclosan in compound chemical disinfectants and daily chemicals by micellar electrokinetic chromatography
    XIE Na1,2, DING Xiaojing2,3*, SONG Baohua1,2, LI Jia2,3, WANG Zhi1*
    2013, 31 (1):  64-70.  DOI: 10.3724/SP.J.1123.2012.08046
    Abstract ( 1367 )   [Full Text(HTML)] () PDF (912KB) ( 195 )  
    A novel method for the separation and determination of o-phthalaldehyde (OPA), p-chloro-m-xylenol (PCMX) and triclosan in daily chemicals and compound chemical disinfectants in a single run by micellar electrokinetic chromatography (MEKC) was established. The factors such as the buffer concentration and pH, the concentration of sodium dodecyl sulfate (SDS), and the sample buffer, were investigated in detail. The analysis was carried out using a 50 μm uncoated capillary of 40.2 cm in total length (effective length: 30 cm). The running buffer was 20 mmol/L Na2B4O7 and 80 mmol/L SDS. The sample buffer was 2 mmol/L Na2B4O7-8 mmol/L SDS (without pH adjustment) containing 10% (v/v) methanol. The detection wavelength was 214 nm. The relative standard deviations (RSDs) of the corrected peak areas of the three components were in the range of 1.1%-3.8%, and the RSDs of migration times were less than 0.9%. The limits of detection (LODs, S/N=3) were 4.0, 0.4 and 0.4 mg/L, and the limits of quantification (LOQs, S/N=10) were 12, 1.2, and 1.2 mg/L for OPA, PCMX and triclosan, respectively. The corrected peak areas and the concentrations of the three components showed good linear relationship within the ranges of 12-2 000 mg/L, 1.2-200 mg/L and 1.2-200 mg/L with the correlation coefficients of 0.9994, 0.9993 and 0.9995 for OPA, PCMX and triclosan, respectively. The method was used for the determination of the three components in compound chemical disinfectants, hand washing liquids, soaps and a toothpaste. The results showed that the three components could be assayed in a single run with simple sample pretreatment, rapidity, accuracy and low cost, and the method is convenient for routine analysis.
    Technical Notes
    Rapid screening of 176 pesticide residues in vegetables by ultra fast liquid chromatography-tandem mass spectrometry
    ZHENG Shuning1, LI Lingyun1, LIN Huan1, ZHAO Wen1, ZHANG Yanguo1, YAO Zhoulin2, LIU Su1*
    2013, 31 (1):  71-78.  DOI: 10.3724/SP.J.1123.2012.07033
    Abstract ( 1469 )   [Full Text(HTML)] () PDF (924KB) ( 418 )  
     A multiresidue analytical method for rapid screening of 176 pesticide residues in vegetables was developed by using ultra fast liquid chromatography-tandem mass spectrometry (UFLC-MS/MS). The vegetable samples were extracted by acetonitrile. It is not necessary for the extract to make a further purification after salting out. Multiple reaction monitoring with information-dependent acquisition of enhanced product ion (MRM-IDA-EPI) was used for the analysis. Based on EPI spectra and chromatographic peak area, identification and quantification of the 176 pesticide residues in vegetables were carried out by using library search technique. All the pesticides had the good linearity within their respective linear ranges (r>0.99). The average recoveries of the 174 pesticides except for carbosulfan and cyromazine were in the range of 72.4% to 126.4% with the relative standard deviations (RSDs) from 1.0% to 18.7%. The limits of detection and quantification of the method were 0.005-2.0 μg/kg and 0.1-10 μg/kg, respectively. The results demonstrated that the method has distinct advantages of rapid speed, high sensitivity and good accuracy. Therefore, this method is suitable for the rapid screening of pesticide residues in vegetables.
    Determination of Huperzine A in the extract of Huperzia serrata by high performance liquid chromatography
    ZHANG Jingcai1, WEI Jie2, ZHONG Hongmin1, GUO Zhimou2*, ZHANG Hua1*
    2013, 31 (1):  79-82.  DOI: 10.3724/SP.J.1123.2012.08038
    Abstract ( 1943 )   [Full Text(HTML)] () PDF (822KB) ( 267 )  
    A high performance liquid chromatographic (HPLC) method was established to determine the Huperzine A in the extract of Huperzia serrata. After extracted by methanol/water/formic acid (10/90/0.2, v/v/v), the sample was filtered for HPLC analysis. The separation was performed on an XCharge C18 column (150 mm×4.6 mm, 5 μm) by gradient elution with water (containing 0.1% (v/v) trifluoroacetic acid) and acetonitrile (containing 0.09%(v/v) trifluoroacetic acid) as the mobile phases. Rapid separation was achieved within 10 min at a flow rate of 2 mL/min with ultraviolet absorption detection at a wavelength of 310 nm. Under the optimized conditions, good linearity was obtained in the range of 2.12-106 mg/L with the correlation coefficient (R2) of about 0.9999. The average recovery was 102.34% with the relative standard deviation (RSD) of 0.46%. The intraday and interday precisions were all below 2%. The results demonstrate that this method is simple, rapid and accurate with good reproducibility, and can be used to evaluate the quality of Huperzia serrata.
    Determination of fluorescent whitening agents in plastic food contact materials by high performance liquid chromatography with fluorescence detector
    JIAO Yanna1,2, DING Li1, ZHU Shaohua1, FU Shanliang1, GONG Qiang1, LI Hui2, WANG Libing1*
    2013, 31 (1):  83-87.  DOI: 10.3724/SP.J.1123.2012.08050
    Abstract ( 1628 )   [Full Text(HTML)] () PDF (1056KB) ( 605 )  
    A method for the determination of fluorescent whitening agents in plastic food contact materials by high performance liquid chromatography (HPLC) with fluorescence detector was developed. The samples were extracted with trichloromethane by sonication for 30 min at 40 ℃. The HPLC method was performed on a column of Eclipse XDB-C18 (250 mm×4.6 mm, 5 μm) by gradient elution using 5 mmol/L ammonium acetate and acetonitrile as the mobile phases, and detected by the fluorescence detector at an excitation wavelength of 350 nm and an emission wavelength of 430 nm. The experimental results indicated that the four fluorescent whitening agents were separated well. The limits of detection (LOD) (S/N=3) were 0.3, 0.1, 0.05, 0.14 mg/L, and the limits of quantification (LOQ) (S/N=10) were 1.0, 0.4, 0.2, 0.5 mg/L for 1,4-bis(4-cyanostyryl)benzene (C.I. 199), 1,4-bis(2-benzoxazolyl)naphthalene (C.I. 367), 4,4′-bis(2-methoxystyryl)biphenyl (C.I. 378) and 2,5-thiophenediylbis (5-tert-butyl-1,3-benzoxazole) (C.I. 184), respectively. Good linearities with correlation coefficients (r2) not less than 0.991 were obtained. The proposed method is simple, accurate, sensitive and can meet the requirements of the routine determination of fluorescent whitening agents in entry-exit products.
    Determination of trace chloride in sodium sulfate of analytical reagent-grade by valve-switching ion chromatography
    ZHANG Tingting1*, WANG Nani2, YE Mingli1, HU Zhongyang1, PAN Guangwen1
    2013, 31 (1):  88-91.  DOI: 10.3724/SP.J.1123.2012.08001
    Abstract ( 1463 )   [Full Text(HTML)] () PDF (1053KB) ( 297 )  
    A valve-switching ion chromatography system was developed for the determination of trace chloride in sodium sulfate using a single pump, a suppressor, two valves and three columns. Using this technique, the trace chloride was eluted from the concentrator column (IonPac TAC-ULP1, 23 mm×5 mm) to the analytical column (IonPac AS18, 250 mm×4 mm), and the sulfate flowed to the waste. Under the optimized separation conditions, the method showed good linearity (r2>0.999) in the range of 0.03-1 mg/L and the average recoveries of chloride were 98.0%-103.0% with the relative standard deviation less than 2%. The limit of detection was 0.01 mg/L (S/N=3). The results demonstrated that this system has the advantages of high sensitivity, facile automation and simple sample pretreatment, which might be a promising approach for the determination of trace chloride in high-purity reagents.