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Chinese Journal of Chromatography
2015, Vol. 33, No. 1
Online: 08 January 2015

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Annual review of capillary electrophoresis technology in 2014 WANG Xiaoqian, ZHAO Xinying, QU Feng, HU Youhao, GONG Rui, WEI Qiang 2015, 33 (1):  4-9.  DOI: 10.3724/SP.J.1123.2014.12025 Abstract ( 587 )   [Full Text(HTML)] () PDF (1210KB) ( 192 )   This paper reviews the capillary electrophoresis (CE) in 2014. Five international and two national conferences are included and the important reports are introduced briefly. The literatures from ISI Web of Science published in 2014 (Jan. 1st to Dec. 15th) are classified and introduced based on the biology and medicine applications, the use of detectors as well as the important analytical chemical journals. In the end, CE developments in 2012-2014 are reviewed and compared.

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Identifying phosphopeptide by searching a site annotated protein database CHENG Kai, WANG Fangjun, BIAN Yangyang, YE Mingliang, ZOU Hanfa 2015, 33 (1):  10-16.  DOI: 10.3724/SP.J.1123.2014.10019 Abstract ( 595 )   [Full Text(HTML)] () PDF (849KB) ( 113 )   Phosphoproteome analysis is one of the important research fields in proteomics. In shotgun proteomics, phosphopeptides could be identified directly by setting phosphorylation as variable modifications in database search. However, search space increases significantly when variable modifications are set in post-translation modifications (PTMs) analysis, which will decrease the identification sensitivity. Because setting a variable modification on a specific type of amino acid residue means all of this amino acid residues in the database might be modified, which is not consistent with actual conditions. Phosphorylation and dephosphorylation are regulated by protein kinases and phosphatases, which can only occur on particular substrates. Therefore only residues within specific sequence are potential sites which may be modified. To address this issue, we extracted the characteristic sequence from the identified phosphorylation sites and created an annotated database containing phosphorylation site information, which allowed the searching engine to set variable modifications only on the serine, threonine and tyrosine residues that were identified to be phosphorylated previously. In this database only annotated serine, threonine and tyrosine can be modified. This strategy significantly reduced the search space. The performance of this new database searching strategy was evaluated by searching different types of data with Mascot, and higher sensitivity for phosphopeptide identification was achieved with high reliability.

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Simultaneous determination of six components in hair dyes by ultra performance liquid chromatographytandem mass spectrometry YOU Feiming 2015, 33 (1):  17-21.  DOI: 10.3724/SP.J.1123.2014.09009 Abstract ( 613 )   [Full Text(HTML)] () PDF (769KB) ( 228 )   A sensitive method was developed for the simultaneous determination of six components which included 4,4'-diaminodiphenylamine sulfate hydrate and 2,4-diaminophenol sulfate, etc. in hair dyes by ultra performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS). After extracted by water through ultrasonic extraction, the samples were analyzed by UPLC-MS/MS. The separation was performed on a Waters BEH-C18 column (100 mm×2.1 mm, 1.7 μm) with gradient elution of 10 mmol/L ammonium acetate and acetonitrile. The electrospray ionization (ESI) source in positive ion mode was used for the analysis of the six components in the multiple reaction monitoring (MRM) mode. The results showed good linear relationships with all the correlation coefficients (R2) more than 0.99. The limits of detection (LODs, S/N=3) for the six components were in the range of 0.26-4.6 mg/kg. The average recoveries of the six components in the spiked samples were in the range of 83.0%-92.2% with the relative standard deviations (RSDs, n=6) of 5.4%-11.2%. The precision, accuracy, mean recoveries and the matrix effects satisfied the requirements of cosmetic sample measurement. The proposed method has been applied to the determination of six dyes in actual samples. This method is simple, accurate and effective for the simultaneous determination of the six components in hair dyes.

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An ultra-high-pressure liquid chromatography/linear ion trap-Orbitrap mass spectrometry method coupled with a diagnostic fragment ions-searching-based strategy for rapid identification and characterization of chemical components in Polygonum cuspidatum PAN Zhiran, LIANG Hailong, LIANG Chaohui, XU Wen 2015, 33 (1):  22-28.  DOI: 10.3724/SP.J.1123.2014.07006 Abstract ( 549 )   [Full Text(HTML)] () PDF (954KB) ( 402 )   A method for qualitative analysis of constituents in Polygonum cuspidatum by ultra-high-pressure liquid chromatography coupled with linear ion trap-Orbitrap mass spectrometry (UHPLC-LTQ-Orbitrap MS) has been established. The methanol extract of Polygonum cuspidatum was separated on a Waters UPLC C18 column using acetonitrile-water (containing formic acid) eluting system and detected by LTQ-Orbitrap hybrid mass spectrometer in negative mode. The targeted components were further fragmented in LTQ and high accuracy data were acquired by Orbitrap MS. The summarized fragmentation pathways of typical reference components and a diagnostic fragment ions-searching-based strategy were used for detection and identification of the main phenolic components in Polygonum cuspidatum. Other clues such as nitrogen rule, even electron rule, degree of unsaturation rule and isotopic peak data were included for the structural elucidation as well. The whole analytical procedure was within 10 min and more than 30 components were identified or tentatively identified. This method is helpful for further phytochemical research and quality control on Polygonum cuspidatum and related preparations.

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Polyamide as an efficient sorbent for simultaneous interference-free determination of three Sudan dyes in saffron and urine using high-performance liquid chromatography-ultra violet detection Iman SAEIDI, Behruz BARFI, Moazameh PAYROVI, Javad FEIZY, Hojat A SHEIBANI, Mina MIRI, Farahnaz GHOLLASI MOUD 2015, 33 (1):  29-34.  DOI: 10.3724/SP.J.1123.2014.08029 Abstract ( 552 )   [Full Text(HTML)] () PDF (624KB) ( 187 )   With polyamide (PA) as an efficient sorbent for solid phase extraction (SPE) of Sudan dyes II, III and Red 7B from saffron and urine, their determination by HPLC was performed. The optimum conditions for SPE were achieved using 7 mL methanol/water (1: 9, v/v, pH 7) as the washing solvent and 3 mL tetrahydrofuran for elution. Good clean-up and high (above 90%) recoveries were observed for all the analytes. The optimized mobile phase composition for HPLC analysis of these compounds was methanol-water (70: 30, v/v). The SPE parameters, such as the maximum loading capacity and breakthrough volume, were also determined for each analyte. The limits of detection (LODs), limits of quantification (LOQs), linear ranges and recoveries for the analytes were 4.6-6.6 μg/L, 13.0-19.8 μg/L, 13.0-5000 μg/L (r2 > 0.99) and 92.5%-113.4%, respectively. The precisions (RSDs) of the overall analytical procedure, estimated by five replicate measurements for Sudan II, III and Red 7B in saffron and urine samples were 2.3%, 1.8% and 3.6%, respectively. The developed method is simple and successful in the application to the determination of Sudan dyes in saffron and urine samples with HPLC coupled with UV detection.

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Determination of seven biothiols in rice by high performance liquid chromatography-fluorescence detection with pre-column derivatization ZHOU Rong, CAO Zhaoyun, MOU Renxiang, LI Zhengxiang, CHEN Mingxue 2015, 33 (1):  35-39.  DOI: 10.3724/SP.J.1123.2014.09024 Abstract ( 683 )   [Full Text(HTML)] () PDF (788KB) ( 210 )   A high performance liquid chromatographic method with fluorescence detection and pre-column derivatization (HPLC-FLD) has been developed for the determination of seven biothiols including Cys, GSH, and phytochelatins (PCs: PC2, PC3, PC4, PC5 and PC6) in rice. The samples were ultrasonically extracted with 0.1% trifluoroacetic acid (TFA) containing 6.3 mmol/L diethylenetriaminepentaacetic acid (DTPA), and then the seven biothiols were derivatized with monobromobimane (mBrB) as derivatization agent in 4-(2-hydroxyethyl)-1-piperazine propanesulfonic acid (HEPPS) buffer solution (pH 8.0). The separation was performed on an Agilent Eclipse Plus C18 column (50 mm×4.6 mm, 5 μm) with gradient elution of 0.1%TFA solution (the pH value was adjusted to 2.5 with hydrochloric acid) and acetonitrile as mobile phases at a flow rate of 0.8 mL/min. The detection was performed at 380 nm for excitation and 470 nm for emission. The calibration curves of the seven biothiols showed good linearity in the concentration range of 0.7-100.0 mg/L with the correlation coefficients (r2)≥0.9991. The limits of detection were 0.03-0.20 mg/L. The recoveries of standard addition were in the range of 89.26%-99.42% with the relative standard deviations (RSDs, n=6) of 2.05%-5.87%. The method is sensitive, accurate, reproducible and suitable for the simultaneous determination of Cys, GSH, PC2, PC3, PC4, PC5 and PC6 in rice.

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Determination of hexachlorocyclohexane and dichlorodi- phenyltrichloroethane residues in honey by gas chromatography-mass spectrometry combined with dispersive liquid-liquid microextraction WANG Dong, HOU Chuanjin, ZHAO Ercheng, JIA Chunhong 2015, 33 (1):  40-45.  DOI: 10.3724/SP.J.1123.2014.09022 Abstract ( 586 )   [Full Text(HTML)] () PDF (810KB) ( 232 )   A gas chromatography-mass spectrometry (GC-MS) method for the determination of hexachlorocyclohexane (BHC) and dichlorodiphenyltrichloroethane (DDT) residues in honey was developed using dispersive liquid-liquid microextraction (DLLME) as sample preparation method. The samples were extracted with chloroform, and concentrated into chloroform by vortex and centrifuging. The analytes were analyzed by GC-MS. The factors affecting the extraction efficiency were investigated, such as the type and volume of extraction and dispersive solvent, extraction time, etc. The matrix effects and method performance were evaluated at the same time. The results indicated that all the eight BHC and DDT pesticides displayed the enhancement of signals due to the matrix effects. The calibration curves were linear in the range of 2-500 μg/L and the correlation coefficients were 0.991-0.998 for the eight BHC and DDT pesticides. The enrichment factors (EF) were 74-96 for the eight pesticides. The recoveries of the eight BHC and DDT pesticides at three spiked levels of 20, 50 and 100 μg/kg were 61.0%-100.1%, while the RSDs were 2.2%-19.5%. The limits of quantification for the eight pesticides were 20 μg/kg, and the limits of detection were 1.0 ng. The developed method is easy, quick and with high performance. It is applicable for the determination of BHC and DDT residues in honey.

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Pyrolysates of novel latent fragrant compound 3,6-dimethyl- 2,5-pyrazinedicarboxylic acid menthol ester LAI Miao, ZHAO Boya, BAO Xiaorong, ZHAO Mingqin, JI Xiaoming, FU Peipei, ZHANG Yujie 2015, 33 (1):  46-51.  DOI: 10.3724/SP.J.1123.2014.07054 Abstract ( 735 )   [Full Text(HTML)] () PDF (1003KB) ( 364 )   In order to develop a new tobacco flavor released at high-temperature, the novel latent fragrant compound 3,6-dimethyl-2,5-pyrazinedicarboxylic acid menthol ester (DPAME) was synthesized by esterification using 2,3,5,6-tetramethylpyrazine and menthol as raw materials. In air atmosphere, the pyrolysis behavior of DPAME was investigated using an on-line pyrolysis-gas chromatography-mass spectrometry (Py-GC-MS) method at three temperature levels of 300, 600 and 900 ℃, separately. The pyrolysis products were directly introduced into GC-MS and were qualitatively and semi-quantitatively analyzed. The results showed that a variety of aroma compounds of aldehydes, 3-p-menthene and menthol were released and identified at 300 ℃. While at 600 ℃ and 900 ℃, flavor alkene class, the alkyl pyrazines, menthol and 3-p-menthene were generated. And the types and relative amounts of pyrazines were significantly increased at these two temperatures. Combined the analytical results of DPAME pyrolysates and the results of sensory evaluation of the cigarette, the possible pyrolysis mechanism was preliminarily speculated. The Py-GC-MS technique for the study of the pyrolysis products of DPAME was convenient and rapid. The investigation provided a reliable theoretical foundation for the perfume reinforcement technology in tobacco products, contributing to the development of cigarette products with better aroma and taste. This method is an accurate and quick way to study the pyrolysis products of latent fragrant substance.

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Feasibility investigation of hydrogen instead of helium as carrier gas in the determination of five organophosphorus pesticides by gas chromatography-mass spectrometry LIU Zhenxue, ZHOU Shixue 2015, 33 (1):  52-57.  DOI: 10.3724/SP.J.1123.2014.07040 Abstract ( 677 )   [Full Text(HTML)] () PDF (759KB) ( 189 )   Helium is almost the only choosable carrier gas used in gas chromatography-mass spectrometry (GC-MS). A mixed standard solution of five organophosphorus pesticides was analyzed by using GC-MS, and hydrogen or helium as carrier gas, so as to study the feasibility of hydrogen instead of helium as carrier gas for the determination of organophosphorus pesticides. Combining a mass spectrum database built by ourselves, the results were deconvolved and identified by Automated Mass Spectral Deconvolution & Identification System (AMDIS32), a software belonging to the workstation of the instrument. Then, the statistical software, IBM SPSS Statistics 19.0 was used for the clustering analysis of the data. The results indicated that when hydrogen was used as carrier gas, the peaks of the pesticides detected were slightly earlier than those when helium used as carrier gas, but the resolutions of the chromatographic peaks were lower, and the fraction good indices (Frac. Good) were lower, too. When hydrogen was used as carrier gas, the signals of the pesticides were unstable, the measuring accuracies of the pesticides were reduced too, and even more, some compounds were undetectable. Therefore, considering the measuring accuracy, the signal stability, and the safety, etc., hydrogen should be cautiously used as carrier gas in the determination of organophosphorus pesticides by GC-MS.

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Determination of the thermodynamic parameters of ionic liquid 1-hexyl-3-methylimidazolium tetrafluoroborate by inverse gas chromatography LI Xiaoping, WANG Qiang, LI Ling, DING Yanping 2015, 33 (1):  58-64.  DOI: 10.3724/SP.J.1123.2014.09018 Abstract ( 644 )   [Full Text(HTML)] () PDF (843KB) ( 272 )   Inverse gas chromatography (IGC) was used to characterize the thermodynamic properties of ionic liquid (IL) 1-hexyl-3-methylimidazolium tetrafluoroborate ([HMIM]BF4) in the temperature range from 343.15 K to 373.15 K. A series of solvents with different chemical natures were used to determine the [HMIM]BF4-solvent interactions. The thermodynamic parameters including Flory-Huggins interaction parameter, partial molar heats of sorption, mixing and evaporation as well as the activity coefficient at infinite dilution were obtained to judge the interactions between [HMIM]BF4 and the selected solvents. In addition, the solubility parameters of [HMIM]BF4 at different temperatures were determined. The results showed that among the selected solvents, n-C6, n-C7, n-C8, n-C9, diethyl ether, tetrahydrofuran, benzene and cyclohexane were poor solvents for [HMIM]BF4, while toluene, m-xylene, methanol, ethanol, dichloromethane, tetrachloromethane, chloroform, acetone, ethyl acetate and methyl acetate were the favorite ones. The solubility parameter of [HMIM]BF4 at room temperature (298.15 K) was 23.70 (J·-3)0.5, which was obtained by the linear extrapolation method. The experiment proved that IGC is a simple and accurate method to obtain the thermodynamic properties of ionic liquids. The obtained thermodynamic parameters revealed the strength of the interactions between the selected solvents and the ionic liquid, which could be used as a reference to the further applications of the ionic liquid.

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Determination of wilforine in honey using solid phase extraction purification and ultra performance liquid chromatography-tandem mass spectrometry LEI Meikang, PENG Fang, DING Tao, ZHU Zitong, XU Jiawen, WU Xiaoqin 2015, 33 (1):  65-67.  DOI: 10.3724/SP.J.1123.2014.08022 Abstract ( 590 )   [Full Text(HTML)] () PDF (726KB) ( 178 )   A method based on solid phase extraction and ultra performance liquid chromatography coupled with tandem mass spectrometry (SPE-UPLC-MS/MS) has been proposed for the determination of wilforine residue in honey. After the sample was dissolved with water, concentrated and purified by an HLB solid phase extraction cartridge, the UPLC separation was performed on a Hypersil GOLD C18 column (50 mm ×2.1 mm, 1.9 μm) utilizing a gradient elution program of methanol (containing 0.15% formic acid) and water as mobile phases at a flow rate of 0.25 mL/min. The determination was carried out with electrospray ion source in the positive mode (ESI+) and multiple reaction monitoring (MRM) mode. The mass concentration of wilforine in the range of 0.01-2 μg/L was linearly correlated with the peak area, and the correlation coefficients was greater than 0.998. The limit of quantification (S/N>10) for wilforine was 0.01 μg/kg. The recoveries were 76.1% to 96.2% in the spiked levels of 0.01, 0.05 and 0.5 μg/kg with the relative standard deviations (RSD, n=6) lower than 10%. The results indicate that the method is rapid, sensitive and accurate, and can be applied for the qualitative and quantitative analysis of wilforine in honey.

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Determination of di(hydrogenated tallow alkyl) dimethyl ammonium compounds in textile auxiliaries by ultra-high performance liquid chromatography-tandem mass spectrometry ZHU Feng 2015, 33 (1):  68-74.  DOI: 10.3724/SP.J.1123.2014.09023 Abstract ( 588 )   [Full Text(HTML)] () PDF (843KB) ( 185 )   A method has been developed for the determination of di(hydrogenated tallow alkyl) dimethyl ammonium compounds (DHTDMAC) in textile auxiliaries by ultra-high performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS). The samples were extracted and diluted with acidified methanol by 5%(v/v) formic acid under ultrasonic assistance. The separation was performed on an Eclipse Plus C18 column (50 mm×2.1 mm, 1.8 μm) using 0.1%(v/v) formic acid solution and methanol as the mobile phases. Identification and quantification were achieved by UPLC-MS/MS with electrospray ionization (ESI) source in positive ion mode and multiple reaction monitoring (MRM) mode. The results indicated that the calibration curve of DHTDMAC showed good linear relationship between peak area and mass concentration in the range of 10-280 μg/L with the correlation coefficient (r2) of 0.9991. The limit of detection (LOD, S/N=3) and the limit of quantification (LOQ, S/N=10) of this method were 3 mg/kg and 10 mg/kg, respectively. The average recoveries from three typical textile auxiliary matrices including dispersant, anti-static agent and fabric softener, at three spiked levels were in the range of 97.2%-108.3% with the relative standard deviations (RSDs) of 1.5%-4.6%. The method is sensitive, accurate, simple and effective for the analysis of DHTDMAC in textile auxiliaries.

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Determination of three isothiazolinone biocides in water-borne adhesives by high performance liquid chromatography ZHOU Xiao, LI Xiaolan, CHEN Zhiyan, YE Changwen, ZHOU Yun, MENG Dongling 2015, 33 (1):  75-79.  DOI: 10.3724/SP.J.1123.2014.10012 Abstract ( 1316 )   [Full Text(HTML)] () PDF (776KB) ( 587 )   A rapid high performance liquid chromatography (HPLC) method was developed for the quantitative analysis of three isothiazolinone biocides (2-methyl-4-isothiazolin-3-one (MI), 5-chloro-2-methyl-4-isothiazolin-3-one (CMI) and 1,2-benzylisothiazolin-3-one (BIT)) in water-borne adhesives. The sample was extracted with methanol-water (1: 1, v/v), and purified by centrifugation and filtration. The isothiazolones were separated on a C18 column with methanol-water as mobile phases under gradient elution and detected with a diode array detector (DAD). The pretreatment factors such as extraction solvent, extraction method, dilution ratio, extraction time were optimized. Under the optimized conditions, the targets had good linearities (r2≥0.9992) in the range of 0.25-10.0 mg/L. The recoveries were between 92% and 103% with the relative standard deviations not more than 4%. The limits of detection (LODs) were between 0.43 mg/kg and 1.14 mg/kg. The limits of quantification (LOQs) were between 1.44 mg/kg and 3.81 mg/kg. The results showed that the method can achieve the purpose of quantitative detection. The analyses of real samples verified the reliability of this method.

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Determination of urea in canned foods by high performance liquid chromatography-fluorescence detection coupled with precolumn derivatization ZENG Qi, ZHANG Jin, XU Dunming, ZHANG Zhigang, KE Zhicheng 2015, 33 (1):  80-83.  DOI: 10.3724/SP.J.1123.2014.08024 Abstract ( 940 )   [Full Text(HTML)] () PDF (973KB) ( 293 )   A method for the determination of urea residue in canned foods by high performance liquid chromatography-fluorescence detection (HPLC-FLD) coupled with precolumn derivatization was established. The sample (5.0 g), including canned edible fungi, fruit, vegetable, fish, and meat was extracted with 20 mL 1%(v/v) acetic acid solution. The extract was centrifuged, filtrated, and then derivatized with xanthydrol. The analysis was completed with HPLC-FLD. A good linear relationship was obtained in the range of 0.1-500 mg/L with the correlation coefficients more than 0.9995. The average recoveries of urea spiked at 0.001-30 g/kg levels in five kinds of canned foods ranged from 80.2% to 109.7% with the RSDs of 2.05%-6.53%. The limit of detection (LOD) was 0.5 mg/kg, and the limit of quantitation (LOQ) was 1.0 mg/kg. The proposed procedure was then applied to the analysis of 168 real samples collected from Xiamen, Fujian Province, China. The existence of urea was found in three pork cans with contents of 10.6, 62.1 and 2.6 mg/kg, respectively. The method is stable, reliable, simple and suitable for the determination of urea in canned foods, and has great potential for routine analysis in foodstuffs.

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Isolation of chemical constituents from Ziziphora clinopodioides Lam. with recycling preparative high performance liquid chromatography LI Guozhu, MENG Qingyan, LUO Bi, GE Zhenhong, LIU Wenjie 2015, 33 (1):  84-89.  DOI: 10.3724/SP.J.1123.2014.09033 Abstract ( 769 )   [Full Text(HTML)] () PDF (1245KB) ( 222 )   The combination of alternate recycling and direct recycling preparative liquid chromatography method was developed for the isolation of chemical constituents from Ziziphora clinopodioides Lam. The crude extract was obtained from Ziziphora clinopodioides Lam. by solvent extraction, column chromatography and reversed-phase (RP) flash chromatography. All the separations were performed with methanol and water as mobile phases and the developed recycling preparative method was used with twin RP columns switched by a two-position ten-way valve for the separation. The mobile phase was recycled in close loop with a two-position six-way valve. The fraction Ⅰ and fraction Ⅱ from reversed-phase flash chromatography were selected for the demonstration of separation power of the proposed protocol, and five compounds were obtained from Ziziphora clinopodioides Lam. The isolated five compounds were identified as pinocembrin-7-O-rutinoside, pinocembrin-7-O-rutinoside, acacetin-7-O-rutinoside, picein and protocatechuic acid with nuclear magnetic resonance (NMR). The experimental results showed that the developed preparation method exhibited higher separation efficiency with less mobile phase used than the reported methods, and could be expected as an effective method for the separation of complex natural products, especially the compounds with similar structures.

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Determination of low-carbon alcohols, aldehydes and ketones in aqueous products of Fischer-Tropsch synthesis by gas chromatography GAI Qingqing, WU Peng, SHI Yulin, BAI Yu, LONG Yinhua 2015, 33 (1):  90-95.  DOI: 10.3724/SP.J.1123.2014.09027 Abstract ( 599 )   [Full Text(HTML)] () PDF (785KB) ( 387 )   A method for the determination of low-carbon (C1-C8) alcohols, aldehydes and ketones in aqueous products of Fischer-Tropsch synthesis was developed by gas chromatography. It included the optimization of separation conditions, the precision and accuracy of determination, and the use of correction factors of the analytes to ethanol for quantification. The aqueous products showed that the correlation coefficients for ethanol in different content ranges were above 0.99, which means it had good linear correlations. The spiked recoveries in the aqueous samples of Fischer-Tropsch synthesis were from 93.4% to 109.6%. The accuracy of the method can satisfy the requirement for the analysis of the aqueous samples of Fischer-Tropsch synthesis. The results showed that the total mass fractions of the major low-carbon alcohols, aldehydes, ketones in aqueous products of Fischer-Tropsch synthesis were about 3%-12%, and the contents of ethanol were the highest (about 1.7%-7.3%). The largest share of the total proportion was n-alcohols, followed by isomeric alcohols, aldehydes and ketones were the lowest. This method is simple, fast, and has great significance for the analysis of important components in aqueous products of Fischer-Tropsch synthesis.

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Surface properties of ZnMgAl hydrotalcite-like compounds by inverse gas chromatography ZHOU Liangqin, FU Dayou, YUAN Dong, FAN Jinlong, TAN Wenyuan 2015, 33 (1):  96-100.  DOI: 10.3724/SP.J.1123.2014.07032 Abstract ( 589 )   [Full Text(HTML)] () The structure of ZnMgAl hydrotalcite-like compounds (ZnMgAl-HTLC) prepared by hydrothermal synthesis was studied by X-ray diffraction (XRD). With a series of polar and non-polar molecules as probes, inverse gas chromatography (IGC) was used to measure the surface properties of ZnMgAl-HTLC. It was found that the XRD pattern of ZnMgAl-HTLC was narrow, sharp and high. The results showed that ZnMgAl-HTLC with a higher purity was obtained by hydrothermal synthesis. The surface adsorption free energy was less than zero. The surface dispersive free energy was 6.02mJ/m2. The acid-base interaction free energy was 5.33 kJ/mol. The adsorption enthalpy was 43.6 kJ/mol, and the adsorption entropy was 0.15 kJ/mol. The IGC method is significant in the study of the surface properties of ZnMgAl-HTLC.