List of Issues

Chinese Journal of Chromatography
2017, Vol. 35, No. 7
Online: 08 July 2017

Previous Issue    Next Issue



For Selected:

Download Citations EndNote Ris BibTeX

Toggle Thumbnails

Select

Rapid determination of spirotetramat and its metabolite residues in milk by ultra performance liquid chromatography-tandem mass spectrometry YI Tinghui, TANG Bobin, ZOU Yun, XI Cunxian, WANG Guomin 2017, 35 (7):  677-682.  DOI: 10.3724/SP.J.1123.2017.03009 Abstract ( 799 )   [Full Text(HTML)] () PDF (889KB) ( 135 )   A method for the rapid and simultaneous determination of spirotetramat (BYI08330) and its four metabolites in milk was developed with ultra performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS). The samples were extracted with acetonitrile for precipitating proteins, degreased with hexane, and analyzed by UPLC-MS/MS in positive electrospray ionization and multiple reaction monitoring (MRM) mode. Good linear relationships between peak areas and mass concentrations of the analytes were obtained in the range of 0.5-50 μ g/L with correlation coefficients greater than 0.998 (n=6). The limits of detection (LODs, S/N=3) and limits of quantification (LOQs, S/N=10) were 0.05-0.30 μ g/L and 0.17-1.00 μ g/L, respectively. The recoveries at the spiked levels of 1.0, 2.0 and 10 μ g/L were in the range of 80.0%-108.8% with relative standard deviations (RSDs) of 4.8%-15.2% (n=6). The method is fast, sensitive and accurate, and can be used to simultaneously determine BYI08330 and its four metabolites in milk.

Select

Application of off-line two dimensional reversed-phase liquid chromatography/supercritical fluid chromatography to the separation of the seeds of Trichosanthes kirilowii Maxim YUAN Yun, XIN Huaxia, PENG Ziyue, FU Qing, JIN Yu 2017, 35 (7):  683-687.  DOI: 10.3724/SP.J.1123.2017.03003 Abstract ( 568 )   [Full Text(HTML)] () PDF (1160KB) ( 141 )   An off-line two dimensional reversed-phase liquid chromatography/supercritical fluid chromatography (2D RPLC/SFC) method was developed for the separation of the seeds of Trichosanthes kirilowii Maxim. (T. kirilowii.). In the experiment, RPLC was used in the first dimension to analyze the samples. And 12 fractions (F1-F12) were obtained according to the chromatographic peak collection mode, the fractions were re-analyzed in both RPLC and SFC modes. The results clearly showed that this 2D method had good orthogonality. The SFC was used as the second dimension. Ethanol-n-hexane (3:7, v/v) was used as a modifier in SFC. The modifier could provide appropriate elution power. When the sample load increased, it could also ensure the solubility of samples. The 2D RPLC/SFC method had obvious advantages for separating the compounds with similar properties, enriching and purifying the trace components. Finally, 150 peaks could be detected. The off-line 2D RPLC/SFC method will be further enlarged to a preparative level for preparation of compounds. The method can provide a practical reference for the purification of chemical constituents and material basis research of the seeds of T. kirilowii. in the future.

Select

Fabrication of acylsemicarbazide-based porous organic polymer for selective enrichment of glycopeptides WANG Hongwei, LIU Zhongshan, PENG Xiaojun, OU Junjie, YE Mingliang 2017, 35 (7):  688-695.  DOI: 10.3724/SP.J.1123.2017.05014 Abstract ( 541 )   [Full Text(HTML)] () PDF (4555KB) ( 154 )   An acylsemicarbazide-based porous organic polymer (POP) was facilely prepared by the polymerization of benzene-1,3,5-tricarbohydrazide (BTZ) and 1,4-phenylene diisocyanate (PDI). The physical properties of as-synthesized material were characterized by Fourier-transform infrared spectroscopy (FT-IR), solid-state cross polarisation magic angle spinning carbon-13 nuclear magnetic resonance (CP-MAS 13C NMR), nitrogen adsorption/desorption measurement, water contact angle and so on. The specific surface area was 166 m2/g, and the water contact angle was 46.4°, exhibiting hydrophilic property of the porous material. Thus, POP-1 was tried to be used for glycopeptides enrichment from tryptic digest of standard protein and complex biosamples in hydrophilic mode. The 19 typical N-linked glycopeptides were identified from 500 fmol tryptic digest of immunoglobulin G (IgG) from human serum by matrix-assisted laser desorption ionization-time of flight mass spectrometry (MALDI-TOF/MS) analysis, meanwhile, 1919 unique glycopeptides with 1350 N-glycosylation sites from 605 different N-linked glycoproteins were identified from 100 μ g mouse liver tryptic digest by capillary liquid chromatography (cLC)-MS/MS analysis. These results demonstrated the great potential of POP-1 for glycoproteome analysis.

Select

Preparation of cysteine-click maltose modified silica as a hydrophilic interaction liquid chromatography material for the enrichment of glycopeptides SUN Xudong, ZHANG Lingyi, ZHANG Weibing 2017, 35 (7):  696-702.  DOI: 10.3724/SP.J.1123.2017.03002 Abstract ( 639 )   [Full Text(HTML)] () PDF (8472KB) ( 109 )   Because of the low abundance of glycoprotein and glycopeptide in complex biological samples, it is urgent to develop an efficient method for glycopeptide enrichment in comprehensive and in-depth glycoproteomes research. Herein, a novel hydrophilic silica was developed through surface modification with cysteine-click maltose (Cys-Mal@SiO2). The developed hydrophilic silica was packed into a solid phase extraction (SPE) column, and applied to the highly selective enrichment and identification of N-linked glycopeptides. The Cys-Mal@SiO2 demonstrated better identification capability over Cys@SiO2, Mal@SiO2 and commercial hydrophilic interaction liquid chromatography (HILIC) in glycopeptide enrichment due to the synergistic effect of the two kinds of hydrophilic molecules. In the selective enrichment of tryptic digest from human immunoglobulin G, glycopeptides with higher signal-to-noises were detected by Cys-Mal@SiO2. In addition, 1551 unique glycopeptides with 906 N-glycosylation sites from 466 different N-linked glycoproteins were identified from the proteins extracted from mouse liver after the enrichment with Cys-Mal@SiO2. In contrast, the numbers of identified glycopeptides, glycoproteins and N-glycosylation sites identified by Cys@SiO2 were 211, 67, 127 respectively less than by Cys-Mal@SiO2, and the corresponding numbers were 289, 76, 193 by Mal@SiO2. These results showed that the developed Cys-Mal@SiO2 is a promising affinity material for N-glycoproteomics research of real complex biological samples.

Select

New C2 symmetric chiral stationary phases based on L-proline derivatives as chains CHEN Long, CHENG Lingping, HE Shanshan, HE Yunchao, WU Yaling, KE Yanxiong, LIANG Xinmiao 2017, 35 (7):  703-711.  DOI: 10.3724/SP.J.1123.2017.02029 Abstract ( 500 )   [Full Text(HTML)] () PDF (1330KB) ( 93 )   C2 symmetric chiral compounds overlap themselves when rotating with an axis of 180° with an axis and have important applications in chiral catalysis and chiral separation fields. A novel C2 symmetric stationary phase based on phenyl substituted L-proline derivatives was prepared and compared with the similar stationary phase based on mono-substituted brush-type stationary phase. The C2 symmetric stationary phase showed higher enantiodiscrimination capability than the mono-substituted stationary phase for 31 acidic, neutral and alkaline analytes. The influence of the substitution groups on the terminal phenyl moiety on enantioselectivity was investigated. In summary, the best separation capability was achieved by the stationary phase with none substitution on the endmost phenyl ring. An unusual thermodynamic behavior of the enantioseparation property was observed on the C2 symmetric stationary phase for some analytes, which showed the different separation mechanism comparing with the corresponding mono-substituted stationary phase. The appearance of this novel chiral stationary phase has an important significance in enriching the type of brush-type stationary phases and widening their applications.

Select

Preparation and performance characterization of gold nanoparticles modified chiral capillary electrochromatography stationary phase XIONG Lele, LI Ruijun, JI Yibing 2017, 35 (7):  712-718.  DOI: 10.3724/SP.J.1123.2017.03019 Abstract ( 894 )   [Full Text(HTML)] () PDF (6314KB) ( 106 )   Gold nanoparticles (GNPs, 15 nm) were prepared and introduced to amino groups derived silica monolithic column. Bovine serum albumin (BSA) was immobilized via covalent modification method onto the carboxylic functionalized GNPs to afford chiral stationary phase (CSP) for enantioseparation. GNPs were well dispersed and successfully incorporated onto the columns with the contents as high as 17.18% by characterization method such as transmission electron microscopy (TEM), ultraviolet (UV)-visible absorption spectra and scanning electron microscopy (SEM). The preparation conditions of the BSA modified CSP were optimized and 10% (v/v) 3-aminopropyltriethoxysilane (APTES) and 15 g/L BSA were selected as appropriate reaction conditions. The enantioseparation performance of the BSA modified CSP has been investigated by capillary electrochromatography (CEC). Enantiomers of tryptophan, ephedrine and atenolol were resolved, and the baseline separation of tryptophan was achieved. Meanwhile, the influences of pH value, buffer concentrations and applied voltages used on the chiral separation were studied, and the optimal separation conditions were 10 mmol/L phosphate buffer at pH 7.4 and 15 kV applied voltages. In comparison with the BSA modified CSP prepared by physical adsorption, the CSP prepared by covalent modification method had better separation results, and the analytes could be separated directly without pre-column derivatization. In addition, the prepared BSA modified CSP exhibited good run to run repeatability with relative standard deviations (RSDs) of the migration times and selectivity factors not more than 2.3% and 0.96%, respectively. This work offers a good thinking for modification with other proteins or other types of chiral selectors.

Select

Determination of pyriminobac-methyl and bispyribac-sodium residues in rice by liquid chromatography-tandem mass spectrometry based on QuEChERS QIN Meiling, CHAI Shuangshuang, MA Youning, GAO Huanhuan, ZHANG Hantong, HE Qiao 2017, 35 (7):  719-723.  DOI: 10.3724/SP.J.1123.2017.02032 Abstract ( 714 )   [Full Text(HTML)] () PDF (1357KB) ( 151 )   A method was developed for the determination of pyriminobac-methyl and bispyribac-sodium residues in rice by liquid chromatography-tandem mass spectrometry (LC-MS/MS) coupled with modified QuEChERS. The samples were extracted with acidified acetonitrile, and then purified by octadecylsilane bonded silica (C18) adsorbents. The analytes were separated on a ZORBAX SB C18 column through a gradient elution using 0.1% (v/v) aqueous formic acid aqueous containing 5 mmol/L ammonium acetate and acetonitrile as mobile phases. Positive electrospray ionization (ESI+) was used. Qualitative work was performed using selected dynamic multiple reaction monitoring (dynamic MRM) mode. Quantization was performed using external standard method. The results showed good linearities of pyriminobac-methyl and bispyribac-sodium with correlation coefficients (r2) not less than 0.996. The limits of detection (LODs) of the method were 0.8 μ g/kg for pyriminobac-methyl, and 3 μ g/kg for bispyribac-sodium. The mean spiked recoveries of pyriminobac-methyl and bispyribac-sodium at three spiked levels were 76.6%-85.6% and 73.0%-86.7%, respectively, and the relative standard deviations (RSDs) of pyriminobac-methyl and bispyribac-sodium were 0.9%-3.4% and 1.2%-5.5%, respectively. This method is simple, rapid, sensitive, and suitable for the simultaneous determination of pyriminobac-methyl and bispyribac-sodium in rice.

Select

Rapid screening the alkaloids of poppy shell in hot pot condiment, beef noodle soup and seasoning by direct analysis in real time-tandem mass spectrometry ZHANG Baile, GAO Lihong, XIE Yingshuang, ZHOU Wei, CHEN Xiaofeng, LEI Chunni, ZHANG Huan 2017, 35 (7):  724-729.  DOI: 10.3724/SP.J.1123.2017.03022 Abstract ( 586 )   [Full Text(HTML)] () PDF (1210KB) ( 122 )   A direct analysis in real time tandem mass spectrometry (DART-MS/MS) method was established for quickly screening five illegally added alkaloids of poppy shell from the hot pot condiment, beef noodle soup and seasoning. The samples were extracted and purified by acetonitrile, and then injected under the conditions of ionization temperature of 300℃, grid electrode voltage of 150 V and sampling rate of 0.8 mm/s using DART in the positive ion mode. The determination was conducted by tandem mass spectrometry in positive ESI mode under multiple reaction monitoring (MRM) mode. The method is simple and rapid, and can meet the requirement of rapid screening and analysis of large quantities of samples.

Select

Determination of tristyrylphenol ethoxylates by high performance liquid chromatography-tandem mass spectrometry ZHANG Peng, ZHAO Nannan, SU Hang, JIN Fen, SHAO Hua, JIN Maojun, WANG Shanshan, SHE Yongxin, ZHENG Lufei, WANG Jing 2017, 35 (7):  730-734.  DOI: 10.3724/SP.J.1123.2017.03037 Abstract ( 810 )   [Full Text(HTML)] () PDF (846KB) ( 167 )   A high performance liquid chromatography-tandem mass spectrometry method for the analysis of tristyrylphenol ethoxylates (TSPnEO) was established. The separation effects of TSPnEO in the four liquid chromatography modes, including reversed-phase liquid chromatography column (XBridge C18, 150 mm×2.1 mm, 3.5 μ m), hydrophilic interaction liquid chromatography column (XBridge HILIC, 150 mm×2.1 mm, 3.5 μ m), amide column (XBridge Amide, 150 mm×2.1 mm, 3.5 μ m) and C18 column (XBridge C18, 50 mm×2.1 mm, 5 μ m) combined with silica column (Nova-Pak Silica, 150 mm×2.1 mm, 4 μ m) were investigated. And the separation effects and sensitivity of TSPnEO in four mobile phases, such as 5 mmol/L ammonium acetate aqueous solution-acetonitrile, 0.1% (v/v) formic acid aqueous solution-acetonitrile, water-acetonitrile and water-methanol, and three eluent gradient conditions were optimized too. The ionization behavior of TSPnEO in electrospray ionization (ESI) was also studied. The results showed that in the ESI positive ion mode, the identified adducts were[M+NH4]+, and the distribution characterization was in Poisson-like distribution. The separation of TSPnEO (n=5-18) was achieved via C18 column combined with the silica column and water-acetonitrile as mobile phases according to the degree of ethoxylation.

Select

Simultaneous determination of plasma indole and skatole in pregnant women with hepatitis B virus infection by high performance liquid chromatography DENG Linlin, ZHEN Qianna, GAO Jieying, JIN Mingchao, DING Min, XU Biao 2017, 35 (7):  735-740.  DOI: 10.3724/SP.J.1123.2017.03025 Abstract ( 626 )   [Full Text(HTML)] () PDF (864KB) ( 171 )   A high performance liquid chromatographic (HPLC) method with fluorescence detection (FD) was established to simultaneously determine plasma indole and skatole. Plasma samples were pretreated by liquid-liquid extraction. Chromatographic separation was accomplished on a Shim-Pack VP-ODS column (150 mm×4. 6 mm, 4.6 μ m) using an isocratic mixture of 15 mmol/L sodium dihydrogen phosphate solution and methanol (40:60, v/v). The fluorescence excitation and emission wavelengths were 274 nm and 340 nm, respectively. The linear ranges were 2.22-88.89 μ g/L for indole and 1.11-44.44 μ g/L for skatole. The detection limits were 0.11 μ g/L and 0.06 μ g/L for indole and skatole, respectively. The recoveries were in the range of 95.5%-112.3% with the relative standard deviations less than 6.8%. The method was successfully applied to the analysis of plasma from healthy pregnant women (n=46) and pregnant women with hepatitis B virus (HBV) infection (n=29). The results showed that plasma indole and skatole levels were significantly different between two groups. In pregnant women with HBV infection, the concentrations of indolic compounds were positively associated with transaminase levels.

Select

Quality evaluation of Yinqiaojiedu tablets by three wavelength fusion fingerprint combined with six components quantitative determination and principal component analysis MA Didi, GONG Dandan, SUN Guoxiang, YANG Fangliang 2017, 35 (7):  741-747.  DOI: 10.3724/SP.J.1123.2017.01015 Abstract ( 723 )   [Full Text(HTML)] () PDF (873KB) ( 130 )   The fusion high performance liquid chromatographic fingerprint combined with quantification and principal component analysis (PCA) was successfully developed, which was applied to assess the quality consistency of 25 Yinqiaojiedu tablets (YQJDTs). The resolution index I was employed as an objective function to evaluate chromatographic conditions. The chromatographic fingerprints were established by reversed-phase high performance liquid chromatography. The wavelengths were set at 230, 279 and 327 nm, separately. Then, the three wavelength fusion fingerprint was developed by the technique of multi-wavelength fusion fingerprint. The linearity, precision, repeatability, stability and accuracy of the method were proved to meet the fingerprint analysis criteria. Subsequently, the systematic quantified fingerprint method was applied for integrative quality discrimination of YQJDTs from both qualitative and quantitative perspectives. The results showed that the quality of 25 YQJDTs from the two manufacturers were completely qualified and well differentiated. The contents of six components were determined simultaneously and combined with fingerprint analysis. It was used to evaluate the quality of YQJDT from the overall and partial points of view. In addition, the PCA of the fusion fingerprint data was applied to get the score plot. It can be clearly distinguished the 25 YQJDT samples from the two manufacturers. The method proposed in this study was comprehensive and reliable, which could be used for a valuable reference to scientifically evaluate and effectively control the quality of YQJDT.

Select

Determination of four polycyclic aromatic hydrocarbons in olive oil by high performance liquid chromatography-fluorescent detection ZHAO Jiaying, LI Xiaomin, LU Xiaohua, ZHANG Qinghe, ZHANG Weibing 2017, 35 (7):  748-754.  DOI: 10.3724/SP.J.1123.2017.03040 Abstract ( 616 )   [Full Text(HTML)] () PDF (1928KB) ( 209 )   A method for the determination of four polycyclic aromatic hydrocarbons (PAHs) such as benzo[a]anthracene, chrysene, benzo[b]fluoranthene and benzo[a]pyrene in olive oil by high performance liquid chromatography-fluorescent detection (HPLC-FLD) was developed. The olive oil samples were diluted with isopropanol and cleaned-up by a solid phase extraction cartridge with π-π specificity. Critical isomers were separated by gradient elution with water-acetonitrile on an Agilent ZORBAX Eclipse PAH column (100 mm×2.1 mm, 1.8 μ m). The calibration was performed by the use of matrix-matched calibration standards. The results showed that there were good linear relationships for the four PAHs in the range of 2.4-40 μ g/L with correlation coefficients of 0.9990-0.9999. The limits of quantification (LOQs) ranged from 0.147 to 0.413 μ g/L, and the recoveries of the spiked samples ranged from 95.5% to 103.2%. The intra-day and inter-day precisions were in the ranges of 0.10%-1.69% and 2.48%-2.93% (n=5), respectively. The method has the characteristics of high sensitivity, low detection limit and good precision, and is suitable for rapid and accurate quantitative detection of the four PAHs in olive oil.

Select

Determination of formaldehyde and acetaldehyde in packaging paper by dansylhydrazine derivatization-high performance liquid chromatography-fluorescence detection GONG Shuguo, LIANG Yong, TANG Liyun, HUANG Ping, DAI Yunhui 2017, 35 (7):  755-759.  DOI: 10.3724/SP.J.1123.2017.03008 Abstract ( 964 )   [Full Text(HTML)] () PDF (847KB) ( 202 )   A high performance liquid chromatography with fluorescence detection (HPLC-FLD) method was developed for the simultaneous determination of formaldehyde and acetaldehyde in packaging paper by dansylhydrazine (DNSH) derivatization. The samples were extracted by derivatization reagent for 30 min, and derived for 24 h. After purifying treatment with a PSA/C18 cartridge, a Diamonsil® C18 column (150 mm×4.6 mm, 5 μ m) was used as stationary phase for separation, the mixtures of acetic acid aqueous solution (pH 2.55)-acetonitrile were used as mobile phases by gradient elution, and the excitation and emission wavelengths were 330 nm and 484 nm, respectively. The results showed that the recoveries of formaldehyde and acetaldehyde spiked in the samples were 81.64%-106.78%, and the relative standard deviations (RSDs) were 2.02%-5.53% (n=5). The limits of detection of formaldehyde and acetaldehyde were 19.2 μ g/kg and 20.7 μ g/kg, respectively. The limits of quantification of formaldehyde and acetaldehyde were 63.9 μ g/kg and 69.1 μ g/kg, respectively. The method is simple, sensitive and reproducible. It provides a basic approach for the determination of trace formaldehyde and acetaldehyde.

Select

Determination of olive oil content in olive blend oil by headspace gas chromatography-mass spectrometry JIANG Wanfeng, ZHANG Ning, ZHANG Fengyan, YANG Zhao 2017, 35 (7):  760-765.  DOI: 10.3724/SP.J.1123.2017.02025 Abstract ( 625 )   [Full Text(HTML)] () PDF (2232KB) ( 119 )   A method for the determination of the content of olive oil in olive blend oil by headspace gas chromatography-mass spectrometry (SH-GC/MS) was established. The amount of the sample, the heating temperature, the heating time, the amount of injection, the injection mode and the chromatographic column were optimized. The characteristic compounds of olive oil were found by chemometric method. A sample of 1.0 g was placed in a 20 mL headspace flask, and heated at 180℃ for 2700 s. Then, 1.0 mL headspace gas was taken into the instrument. An HP-88 chromatographic column was used for the separation and the analysis was performed by GC/MS. The results showed that the linear range was 0-100%(olive oil content). The linear correlation coefficient (r2) was more than 0.995, and the limits of detection were 1.26%-2.13%. The deviations of olive oil contents in the olive blend oil were from -0.65% to 1.02%, with the relative deviations from -1.3% to 6.8% and the relative standard deviations from 1.18% to 4.26% (n=6). The method is simple, rapid, environment friendly, sensitive and accurate. It is suitable for the determination of the content of olive oil in olive blend oil.

Select

Analysis of hydrogen isotopes by gas chromatography using a MnCl2 coated γ-Al2O3 capillary packed column CHEN Ping, FU Xiaolong, HU Peng, XIAO Chengjian, REN Xingbi, XIA Xiulong, WANG Heyi 2017, 35 (7):  766-771.  DOI: 10.3724/SP.J.1123.2017.02028 Abstract ( 554 )   [Full Text(HTML)] () PDF (3686KB) ( 149 )   The conventional packed column gas chromatographic analysis of hydrogen isotopes has low column efficiency, broad peak and long retention time. In this work, a γ-Al2O3 with MnCl2 coated capillary packed column was tested at cryogenic temperature. The systematic column efficiency analysis and the hydrogen isotopes analytical technique research had been carried out. The results showed that, the γ-Al2O3 with MnCl2 coating could greatly improve the surface degree of order, pore structure and adsorption properties. Also the o-H2 peak and p-H2 peak were eluted in a single area. The γ-Al2O3 with MnCl2 coating was packed into a 0.53 mm inner diameter and 1.0 m long fused silica capillary column. It had a good linear relationship used this column with thermal conductivity detector (TCD) to detect the volume concentrations of hydrogen isotopes from 1 to 10 mL/L, and the relative error was less than 5% for low concentration sample testing. For H2, HD and D2, the retention times can be shortened to 39, 46 and 60 s, respectively. The limits of detection were reduced to 0.046, 0.067 and 0.072 mL/L, respectively. Compared with conventional packed column, capillary packed column had sharper peak form, higher separation degree of adjacent components, shorter retention time and lower detection limits. The above results indicate that the capillary packed column with TCD detector can be used for fast detection of low concentration of hydrogen isotopes and their online analysis.

Select

Determination of microcystins in algal bloom samples by ultra performance liquid chromatography-tandem mass spectrometry and elimination of their matrix effects SHEN Fei, XU Yanjuan, JIANG Sheng, ZHAO Bin, SHI Junzhe, CHEN Jing 2017, 35 (7):  772-777.  DOI: 10.3724/SP.J.1123.2017.03046 Abstract ( 688 )   [Full Text(HTML)] () PDF (1118KB) ( 144 )   A rapid and simple method was commonly used for the determination of microcystins by ultra performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS). The reliability, accuracy and sensitivity of LC-MS/MS determination were affected by the matrix effect because of the complex matrices in algal bloom samples. In this study, the matrix interference and matrix effect problems were effectively reduced or eliminated by diluting samples, optimizing gradient elution programs, and reducing injection volumes. The correlation coefficients (r2) of the seven microcystins were ≥ 0.99. The limits of detection and limits of quantification ranged from 0.064 μ g/L to 0.103 μ g/L and 0.213 μ g/L to 0.343 μ g/L, respectively. Algal bloom samples were determined by diluting 10 times and injecting 5 μ L of sample volume. The method provides some references for the determination of microcystins. It is of great significance for ensuring the safety of drinking water source.

Select

Determination of 20 pyrethroid residues in vegetable foods by gas chromatography-tandem mass spectrometry QU Li, LI You, ZENG Jing, SHENG Yonggang, YI Xionghai, CHENG Jia 2017, 35 (7):  778-784.  DOI: 10.3724/SP.J.1123.2017.01012 Abstract ( 623 )   [Full Text(HTML)] () PDF (2477KB) ( 119 )   A method of gas chromatography-tandem mass spectrometry (GC-MS/MS) was developed for the simultaneous determination of 20 pyrethroid residues in vegetable foods. The samples were extracted by acetone-n-hexane (1:1, v/v), cleaned up by activated charcoal column and quantified by external standard method. The correlation coefficients (r2) of all the 20 pyrethroid pesticides in the range of 0.005-1.0 mg/L were not less than 0.990. The limits of detection (LODs) were 2.0 μ g/kg when signal/noise (S/N) > 3. The limits of quantification (LOQs) were 5.0 μ g/kg (S/N > 10). For recovery test, there were three levels (low, medium and high) spiked in 11 matrices. The average recoveries of the method were 75.2%-107% and the relative standard deviations (RSDs, n=6) were 3.08%-12.1%. The results demonstrated that the method is simple and has specific pretreatment steps. The method is suitable for the screening and confirmation of the 20 pyrethroid pesticides in vegetable foods.