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2019 Volume 47 Issue 3
2019, 47(3): 323-334
doi: 10.19756/j.issn.0253-3820.181586
Abstract:
Chlorinated paraffins (CPs) are a new class of persistent organic pollutants and have aroused great concern of many environmental scientists due to their ubiquity in various environmental media and biotas. Given their relative low levels in environmental samples, CPs need to be enriched and cleaned up before instrumental analysis. CPs consist of thousands of congeners and isomers, thus posing grand challenges to eliminate the mass interference by homologues and other organohalogen compounds during instrumental examination. Fortunately, high-resolution mass spectrometry (HRMS) owns the powerful ability to solve this key problem owing to its high mass resolution. This review introduced the methods of pretreatment and instrumental analysis of CPs-containing samples in the environment, mainly illustrating the application of gas chromatography and liquid chromatography coupled with HRMS (i.e. GC-HRMS and LC-HRMS). The existing issues and prospects of future study were also discussed.
Chlorinated paraffins (CPs) are a new class of persistent organic pollutants and have aroused great concern of many environmental scientists due to their ubiquity in various environmental media and biotas. Given their relative low levels in environmental samples, CPs need to be enriched and cleaned up before instrumental analysis. CPs consist of thousands of congeners and isomers, thus posing grand challenges to eliminate the mass interference by homologues and other organohalogen compounds during instrumental examination. Fortunately, high-resolution mass spectrometry (HRMS) owns the powerful ability to solve this key problem owing to its high mass resolution. This review introduced the methods of pretreatment and instrumental analysis of CPs-containing samples in the environment, mainly illustrating the application of gas chromatography and liquid chromatography coupled with HRMS (i.e. GC-HRMS and LC-HRMS). The existing issues and prospects of future study were also discussed.
2019, 47(3): 335-346
doi: 10.19756/j.issn.0253-3820.181626
Abstract:
The development and application of ambient ionization and miniature mass spectrometry are current research focus in chemical measurements. The analytical technology based on ambient ionization coupled with miniature mass spectrometry can bypass chromatographic separation and eliminate or simplify sample pretreatment process. The protocol breaks through the drawbacks of labor-intensive and time-consuming of traditional analytical methodologies, and can be used for the rapid and on-site analysis with high sensitivity and high throughput. In this paper, research progress of ambient ionization and miniature mass spectrometry as well as their applications in the fields of food safety, consumer product safety, public security, life science and environmental monitoring have been reviewed, and future trends and prospective have been discussed, which may provide a technical guidance for the researchers engaged in relevant fields.
The development and application of ambient ionization and miniature mass spectrometry are current research focus in chemical measurements. The analytical technology based on ambient ionization coupled with miniature mass spectrometry can bypass chromatographic separation and eliminate or simplify sample pretreatment process. The protocol breaks through the drawbacks of labor-intensive and time-consuming of traditional analytical methodologies, and can be used for the rapid and on-site analysis with high sensitivity and high throughput. In this paper, research progress of ambient ionization and miniature mass spectrometry as well as their applications in the fields of food safety, consumer product safety, public security, life science and environmental monitoring have been reviewed, and future trends and prospective have been discussed, which may provide a technical guidance for the researchers engaged in relevant fields.
2019, 47(3): 347-354
doi: 10.19756/j.issn.0253-3820.181716
Abstract:
In vivo chemical analysis is an important aspect in exploring brain functions. Brain function realization depends on multiple chemical substances working together. Sole chemical detection is difficult to clarify the chemical signal transmission and disease occurrence. Thus, it is particularly important to simultaneous determination of multiple biological species in the brain. In this study, we designed and constructed a dual-functional electrochemical biosensor for simultaneous determination of glutamate and Ca2+. The co-modified Pt-microelectrode of GluOx and Pt NPs was served as amperometric glutamate microelectrode. By incorporating with potentiometric all-solid-state Ca-ISME, the dual function microelectrode (DFME) biosensor was developed for simultaneous monitoring glutamate and Ca2+ without crosstalk between the two signals. The DFME biosensor showed good selectivity towards common interferences, as well as low detection limits (0.5 μmol/L for glutamate and 1 μmol/L for Ca2+), which met the needs of in vivo analysis. The developed biosensor was successfully applied to real-time monitoring of glutamate and Ca2+ in live rat brain during spreading depression (SD) and ischemia processes. This study provided a simple and effective approach for in vivo analysis of two or more chemical substances, which was helpful for understanding of brain physiological and pathological processes.
In vivo chemical analysis is an important aspect in exploring brain functions. Brain function realization depends on multiple chemical substances working together. Sole chemical detection is difficult to clarify the chemical signal transmission and disease occurrence. Thus, it is particularly important to simultaneous determination of multiple biological species in the brain. In this study, we designed and constructed a dual-functional electrochemical biosensor for simultaneous determination of glutamate and Ca2+. The co-modified Pt-microelectrode of GluOx and Pt NPs was served as amperometric glutamate microelectrode. By incorporating with potentiometric all-solid-state Ca-ISME, the dual function microelectrode (DFME) biosensor was developed for simultaneous monitoring glutamate and Ca2+ without crosstalk between the two signals. The DFME biosensor showed good selectivity towards common interferences, as well as low detection limits (0.5 μmol/L for glutamate and 1 μmol/L for Ca2+), which met the needs of in vivo analysis. The developed biosensor was successfully applied to real-time monitoring of glutamate and Ca2+ in live rat brain during spreading depression (SD) and ischemia processes. This study provided a simple and effective approach for in vivo analysis of two or more chemical substances, which was helpful for understanding of brain physiological and pathological processes.
2019, 47(3): 355-362
doi: 10.19756/j.issn.0253-3820.181661
Abstract:
Protein ubiquitination modification plays an important role in the occurrence, development and metastasis of colorectal cancer. In this work, the total protein extracted from colorectal cancer tissues was hydrolyzed by trypsin to obtain a peptide mixture. Then the peptide mixture containing-GG tag was enriched and purified by immunoprecipitation technique. Finally, the enriched peptides were analyzed by liquid chromatography-mass spectrometry (LC-MS) and the proteins were identified by database search. The results showed that 2036 peptides belonging to 328 proteins were identified in colorectal cancer tissues. Among them, 1497 were the modified peptides containing-GG tag, which were derived from 287 proteins. Apart from most of the peptides containing one-GG tag, 31 peptides containing two-GG tags and 3 peptides containing three-GG tags were identified. Among the identified ubiquitinated proteins, many proteins were found to be closely associated with colorectal cancer, including Prothymosin alpha, Transforming acidic coiled-coil-containing protein 3, Neutral amino acid transporter B (0). Bioinformatics analysis of the identified ubiquitinated proteins showed that ubiquitinated proteins in colorectal cancer tissues were enriched in a variety of basic biological processes and molecular functions, and were distributed in various subcellular organelles and extracellular matrix components. This study provided a specific and effective method for studying the types and distribution of ubiquitinated proteins in colorectal cancer tissues. The results could be used as primary data for further studying the molecular mechanism of ubiquitination regulation in colorectal cancer.
Protein ubiquitination modification plays an important role in the occurrence, development and metastasis of colorectal cancer. In this work, the total protein extracted from colorectal cancer tissues was hydrolyzed by trypsin to obtain a peptide mixture. Then the peptide mixture containing-GG tag was enriched and purified by immunoprecipitation technique. Finally, the enriched peptides were analyzed by liquid chromatography-mass spectrometry (LC-MS) and the proteins were identified by database search. The results showed that 2036 peptides belonging to 328 proteins were identified in colorectal cancer tissues. Among them, 1497 were the modified peptides containing-GG tag, which were derived from 287 proteins. Apart from most of the peptides containing one-GG tag, 31 peptides containing two-GG tags and 3 peptides containing three-GG tags were identified. Among the identified ubiquitinated proteins, many proteins were found to be closely associated with colorectal cancer, including Prothymosin alpha, Transforming acidic coiled-coil-containing protein 3, Neutral amino acid transporter B (0). Bioinformatics analysis of the identified ubiquitinated proteins showed that ubiquitinated proteins in colorectal cancer tissues were enriched in a variety of basic biological processes and molecular functions, and were distributed in various subcellular organelles and extracellular matrix components. This study provided a specific and effective method for studying the types and distribution of ubiquitinated proteins in colorectal cancer tissues. The results could be used as primary data for further studying the molecular mechanism of ubiquitination regulation in colorectal cancer.
2019, 47(3): 363-370
doi: 10.19756/j.issn.0253-3820.181529
Abstract:
The copper oxide/zinc oxide (CuO/ZnO) heterostructure nanoflower was prepared by low-temperature hydrothermal method. A new film-type acetone gas sensor was designed by transferring CuO/ZnO nanoflower onto aluminum plate with platinum-inter digital electrodes using dip-coating method. The crystalline phase and microstructure of CuO/ZnO nanoflower were displayed using X-ray diffraction (XRD), scanning electron microscope (SEM) and high resolution transmission electron microscopy (HRTEM). Sensitive mechanism and electrochemical characteristic of CuO/ZnO were analyzed by X-ray photoelectron spectroscopy (XPS). These characteristic tests of acetone gas sensor were carried out on the traits of sensitive performance, temperature, dynamic response, selectivity and stability in gas sensor test system. The conclusion demonstrated that the acetone gas sensor based on CuO/ZnO nanoflower presented a good linear range (10-300 mg/m3 acetone) at the operating temperature of 200℃. Dynamic response time and recover time of sensor to 100 mg/m3 acetone were 1.8 and 10.7 s, respectively. This kind of sensor showed good anti-disturbance to these gases, such as NO, CO, Formaldehyde, methanol and 1,3-butadiene. Standard deviation of acetone sensor response was 0.107 after it was applied continually on automobile about 50 days.
The copper oxide/zinc oxide (CuO/ZnO) heterostructure nanoflower was prepared by low-temperature hydrothermal method. A new film-type acetone gas sensor was designed by transferring CuO/ZnO nanoflower onto aluminum plate with platinum-inter digital electrodes using dip-coating method. The crystalline phase and microstructure of CuO/ZnO nanoflower were displayed using X-ray diffraction (XRD), scanning electron microscope (SEM) and high resolution transmission electron microscopy (HRTEM). Sensitive mechanism and electrochemical characteristic of CuO/ZnO were analyzed by X-ray photoelectron spectroscopy (XPS). These characteristic tests of acetone gas sensor were carried out on the traits of sensitive performance, temperature, dynamic response, selectivity and stability in gas sensor test system. The conclusion demonstrated that the acetone gas sensor based on CuO/ZnO nanoflower presented a good linear range (10-300 mg/m3 acetone) at the operating temperature of 200℃. Dynamic response time and recover time of sensor to 100 mg/m3 acetone were 1.8 and 10.7 s, respectively. This kind of sensor showed good anti-disturbance to these gases, such as NO, CO, Formaldehyde, methanol and 1,3-butadiene. Standard deviation of acetone sensor response was 0.107 after it was applied continually on automobile about 50 days.
2019, 47(3): 371-379
doi: 10.19756/j.issn.0253-3820.181571
Abstract:
The inclusion behavior, inclusion capacity and inclusion mode of pinocembrin (PIN) with dimethyl-β-cyclodextrin (DM-β-CD) and trimethyl-β-cyclodextrin (TM-β-CD) were characterized by X-ray diffraction, differential scanning calorimetry, scanning electron microscopy, UV-visible spectral titration and molecular docking. The results showed that the packing ratio of PIN/DM-β-CD complex and PIN/TM-β-CD complex was 1:1. The water solubility of PIN respectively increased 817 times and 575 times in the inclusion complex with DM-β-CD and TM-β-CD. Molecular docking showed the pinocembrin entered from the large end of the DM-β-CD molecule and penetrated through the cavity. The A and B rings of the PIN were respectively located at the big and small ends of the cyclodextrin molecule. For the TM-β-CD, only A and C rings of the PIN entered cavity of cyclodextrin.
The inclusion behavior, inclusion capacity and inclusion mode of pinocembrin (PIN) with dimethyl-β-cyclodextrin (DM-β-CD) and trimethyl-β-cyclodextrin (TM-β-CD) were characterized by X-ray diffraction, differential scanning calorimetry, scanning electron microscopy, UV-visible spectral titration and molecular docking. The results showed that the packing ratio of PIN/DM-β-CD complex and PIN/TM-β-CD complex was 1:1. The water solubility of PIN respectively increased 817 times and 575 times in the inclusion complex with DM-β-CD and TM-β-CD. Molecular docking showed the pinocembrin entered from the large end of the DM-β-CD molecule and penetrated through the cavity. The A and B rings of the PIN were respectively located at the big and small ends of the cyclodextrin molecule. For the TM-β-CD, only A and C rings of the PIN entered cavity of cyclodextrin.
2019, 47(3): 380-387
doi: 10.19756/j.issn.0253-3820.181639
Abstract:
As a typical of emerging persistent organic pollutant, perfluorooctane sulfonate (PFOS) and its salt cause ecosystem pollution due to their properties of environmental persistence, genetic toxicity, bio-accumulation and long-range transportation. In this study, NaYF4:Yb,Er upconversion luminescence particle which had low toxicity, high photostability and good water solubility were prepared, and then modified by N,O-bis(trimethylsilyl) trifluoroacetamide (BSTFA) to obtain NaYF4:Yb,Er@SiO2-BSTFA. The luminescent material was used as fluorescence probe to interact with PFOS and a new method for fluorescent analysis of PFOS in water was hence established. In Britton-Robinson(BR, pH 6.30) buffer solution, PFOS can rapidly combine with NaYF4:Yb,Er@SiO2-BSTFA by fluorine-fluorine interaction, resulting in the fluorescence quenching of NaYF4:Yb,Er@SiO2-BSTFA in some extent. The study shows that the reduced fluorescence intensity at 545 nm are in proportional to the concentration of PFOS in the range of 3-100 nmol/L(R2=0.9985), with a detection limit (3σ) of 2.43 nmol/L. The proposed method for detection of PFOS showed obvious advantages compared with those methods reported in the literatures. The selectivity and interference experiments results indicated that the fluorescence probe had good selective response to PFOS in the presence of other common ions and PFOS analogues in water. The method was successfully applied to the determination of PFOS in real water samples with RSD ≤ 9.8% (n=5) and the recovery was 85.8%-118.6%.
As a typical of emerging persistent organic pollutant, perfluorooctane sulfonate (PFOS) and its salt cause ecosystem pollution due to their properties of environmental persistence, genetic toxicity, bio-accumulation and long-range transportation. In this study, NaYF4:Yb,Er upconversion luminescence particle which had low toxicity, high photostability and good water solubility were prepared, and then modified by N,O-bis(trimethylsilyl) trifluoroacetamide (BSTFA) to obtain NaYF4:Yb,Er@SiO2-BSTFA. The luminescent material was used as fluorescence probe to interact with PFOS and a new method for fluorescent analysis of PFOS in water was hence established. In Britton-Robinson(BR, pH 6.30) buffer solution, PFOS can rapidly combine with NaYF4:Yb,Er@SiO2-BSTFA by fluorine-fluorine interaction, resulting in the fluorescence quenching of NaYF4:Yb,Er@SiO2-BSTFA in some extent. The study shows that the reduced fluorescence intensity at 545 nm are in proportional to the concentration of PFOS in the range of 3-100 nmol/L(R2=0.9985), with a detection limit (3σ) of 2.43 nmol/L. The proposed method for detection of PFOS showed obvious advantages compared with those methods reported in the literatures. The selectivity and interference experiments results indicated that the fluorescence probe had good selective response to PFOS in the presence of other common ions and PFOS analogues in water. The method was successfully applied to the determination of PFOS in real water samples with RSD ≤ 9.8% (n=5) and the recovery was 85.8%-118.6%.
2019, 47(3): 388-393
doi: 10.19756/j.issn.0253-3820.181737
Abstract:
Long nanoLC columns have been used in proteomics to improve the resolution and detectability of peptides to enhance protein identification number and analysis confidence. In this study, based on a nanoflow liquid chromatography-electrospray ionization mass spectrometry platform, the performance of a 1.5-m long packed nanoLC column and its applicability in proteomics were investigated. Compared with the commonly used short length nanoLC column, the long packed column achieved excellent resolution for the complex peptide mixture. The proteomics data showed that, using the 1.5-m long nanoLC column, the numbers of peptide spectrum matches, the identified peptides, the unique peptides and the protein groups were increased by 83.6%, 74.4%, 75.0% and 38.4%, respectively. The results demonstrated that the packed long nanoLC columns could be used as a new separation tool for high-resolution proteomics.
Long nanoLC columns have been used in proteomics to improve the resolution and detectability of peptides to enhance protein identification number and analysis confidence. In this study, based on a nanoflow liquid chromatography-electrospray ionization mass spectrometry platform, the performance of a 1.5-m long packed nanoLC column and its applicability in proteomics were investigated. Compared with the commonly used short length nanoLC column, the long packed column achieved excellent resolution for the complex peptide mixture. The proteomics data showed that, using the 1.5-m long nanoLC column, the numbers of peptide spectrum matches, the identified peptides, the unique peptides and the protein groups were increased by 83.6%, 74.4%, 75.0% and 38.4%, respectively. The results demonstrated that the packed long nanoLC columns could be used as a new separation tool for high-resolution proteomics.
2019, 47(3): 394-402
doi: 10.19756/j.issn.0253-3820.181653
Abstract:
In combination with 2,4-dinitrophenylhydrazine (DNPH) pre-column derivatization, an ultrasound-assisted magnetic solid phase extraction method with Fe3O4-grafted nitrogen-doped graphene (Fe3O4/N-G) nanomaterials as magnetic adsorbent was developed for the determination of acetone, acrolein, butenal, n-butanal, cyclohexanone and hexanal in environmental water samples by ultra performance liquid chromatography-high resolution mass spectrometry (UPLC-HRMS). The derivation conditions were optimized by single-factor experiments as follows:the pH of water sample was adjusted to 3.0, and derivatization was performed for 40 min at 40℃ with 500 times of DNPH. As a result, the conversion ratios of 6 carbonyl compounds were in the range of 52.1%-86.6%. Several significant factors that affected the magnetic solid-phase extraction efficiency including the amount of magnetic nanoparticles, salt concentration and kinds of desorption solvent were also optimized using a response surface methodology. The optimal conditions were as follows:4.7 mg of Fe3O4/N-G was dispersed into 100 mL of water with ultrasonic extraction for 10 s. Then the adsorbents were separated by a magnet and eluted with 2 mL of acetonitrile. Finally, the eluent was dried under a mild stream of nitrogen gas and reconstituted with acetonitrile and water (1:1, V/V) for the subsequent UPLC-HRMS analysis. It was obvious that the excessive DNPH could be almost eliminated by the MPSE process. Under the optimal conditions, a good linearity was obtained in the concentration range of 2-100 ng/L, with correlation coefficients ranged from 0.9980 to 0.9995. The limits of detection (LODs, S/N=3) and the limits of quantification (LOQs, S/N=10) ranged from 0.05 to 0.20 ng/L and 0.20 to 0.96 ng/L, respectively. The average recoveries at three spiked levels ranged from 74.1% to 101.0% with the inter-and intra-day precisions (n=6) of less than 6.3%. Moreover, the trace level of acetone, acrolein, butenal, n-butanal, and hexanal in real water samples has been successfully detected using the proposed method. Attributed to the excellent performances of Fe3O4/N-G, the proposed method was demonstrated to be simple, quick and high sensitive for the trace analysis of carbonyl compounds in water samples.
In combination with 2,4-dinitrophenylhydrazine (DNPH) pre-column derivatization, an ultrasound-assisted magnetic solid phase extraction method with Fe3O4-grafted nitrogen-doped graphene (Fe3O4/N-G) nanomaterials as magnetic adsorbent was developed for the determination of acetone, acrolein, butenal, n-butanal, cyclohexanone and hexanal in environmental water samples by ultra performance liquid chromatography-high resolution mass spectrometry (UPLC-HRMS). The derivation conditions were optimized by single-factor experiments as follows:the pH of water sample was adjusted to 3.0, and derivatization was performed for 40 min at 40℃ with 500 times of DNPH. As a result, the conversion ratios of 6 carbonyl compounds were in the range of 52.1%-86.6%. Several significant factors that affected the magnetic solid-phase extraction efficiency including the amount of magnetic nanoparticles, salt concentration and kinds of desorption solvent were also optimized using a response surface methodology. The optimal conditions were as follows:4.7 mg of Fe3O4/N-G was dispersed into 100 mL of water with ultrasonic extraction for 10 s. Then the adsorbents were separated by a magnet and eluted with 2 mL of acetonitrile. Finally, the eluent was dried under a mild stream of nitrogen gas and reconstituted with acetonitrile and water (1:1, V/V) for the subsequent UPLC-HRMS analysis. It was obvious that the excessive DNPH could be almost eliminated by the MPSE process. Under the optimal conditions, a good linearity was obtained in the concentration range of 2-100 ng/L, with correlation coefficients ranged from 0.9980 to 0.9995. The limits of detection (LODs, S/N=3) and the limits of quantification (LOQs, S/N=10) ranged from 0.05 to 0.20 ng/L and 0.20 to 0.96 ng/L, respectively. The average recoveries at three spiked levels ranged from 74.1% to 101.0% with the inter-and intra-day precisions (n=6) of less than 6.3%. Moreover, the trace level of acetone, acrolein, butenal, n-butanal, and hexanal in real water samples has been successfully detected using the proposed method. Attributed to the excellent performances of Fe3O4/N-G, the proposed method was demonstrated to be simple, quick and high sensitive for the trace analysis of carbonyl compounds in water samples.
2019, 47(3): 403-409
doi: 10.19756/j.issn.0253-3820.181724
Abstract:
Because inductively coupled plasma mass spectrometry(ICP-MS) could not be used for determination of trace Fe in high purity rare earths, an inductively coupled plasma-tandem mass spectrometry (ICP-MS/MS) method was proposed. The mass spectral technique based on the oxygen reaction cell was used to optimize the instrument parameters, the flow rate of O2 was adjusted to 2.0 mL/min, and the matrix injection concentration was determined to be 3.00 g/L, as well as the internal standard In was used for the calibration. Then, the isotope 56Fe+ ion with abundance of 91.68% was selected as the analysis target. With Q1=56/Q2=72, the collision reaction of O2 with 56Fe+ was carried out to generate the target product of 56Fe16O+, which performed effectively to eliminate the mass spectrum interference of polyatomic ion of 40Ar16O+, 40Ca16O+ and 37Cl18OH+. So that it could accurately determine the trace impurities of Fe content in 15 kinds of high purity rare earth oxide and 4 kinds of high purity rare earth metals of cerium, neodymium, yttrium, and praseodymium-neodymium. According to the selected analysis conditions, the linear correlation coefficient of the calibration curve was greater than 0.9999, the detection limit was 68 μg/g, the relative standard deviations (RSD, n=11) were 2.1%-4.3%, and the recoveries were 95%-105%. This method is simple and environmentally friendly, and suitable for the rapid determination of trace of Fe in high purity rare earth metals and their oxides.
Because inductively coupled plasma mass spectrometry(ICP-MS) could not be used for determination of trace Fe in high purity rare earths, an inductively coupled plasma-tandem mass spectrometry (ICP-MS/MS) method was proposed. The mass spectral technique based on the oxygen reaction cell was used to optimize the instrument parameters, the flow rate of O2 was adjusted to 2.0 mL/min, and the matrix injection concentration was determined to be 3.00 g/L, as well as the internal standard In was used for the calibration. Then, the isotope 56Fe+ ion with abundance of 91.68% was selected as the analysis target. With Q1=56/Q2=72, the collision reaction of O2 with 56Fe+ was carried out to generate the target product of 56Fe16O+, which performed effectively to eliminate the mass spectrum interference of polyatomic ion of 40Ar16O+, 40Ca16O+ and 37Cl18OH+. So that it could accurately determine the trace impurities of Fe content in 15 kinds of high purity rare earth oxide and 4 kinds of high purity rare earth metals of cerium, neodymium, yttrium, and praseodymium-neodymium. According to the selected analysis conditions, the linear correlation coefficient of the calibration curve was greater than 0.9999, the detection limit was 68 μg/g, the relative standard deviations (RSD, n=11) were 2.1%-4.3%, and the recoveries were 95%-105%. This method is simple and environmentally friendly, and suitable for the rapid determination of trace of Fe in high purity rare earth metals and their oxides.
2019, 47(3): 410-414
doi: 10.19756/j.issn.0253-3820.181691
Abstract:
A method for determination of thionyl chloride(SOCl2) residue in terephthaloyl chloride by inductively coupled plasma-optical emission spectrometry(ICP-OES) was developed. The samples were firstly dissolved with organic solvents and then subjected to liquid-liquid extraction, by which the hydrolization of thionyl chloride could lead to the formation of inorganic sulfate, which was then accurately determined by ICP-OES and the content of thionyl chloride residue thus could be calculated. The type of the organic solvent and its volume to sample mass ratio were optimized, and it was found that the sample could be readily dissolved in carbon tetrachloride as the solvent and the ratio of solvent volume to sample mass being 10 (mL:g). Also, the conditions for the extraction procedure were studied, and it was found that when the aqueous phase solution contained 10% (V/V) nitric acid and 2% (V/V) hydrogen peroxide and the shaking time was kept in about 2 min, the full hydrolization of thionyl chloride and the complete oxidation of H2SO3 could be accomplished, as well as a quick separation of the two organic/water phase was realized. The results showed that the limit of detection (LOD, 3s) of the method was 0.22 mg/kg (calculated as S), the relative standard deviation (RSD) was 2.1% for six real sample analysis, and the recoveries of spiked test were 92.7%-104.6%. The established method was finally applied to the analysis of the real samples collected from the purification process of the terephthaloyl chloride production plant and the results were highly in accordance with theoretically predicted value.
A method for determination of thionyl chloride(SOCl2) residue in terephthaloyl chloride by inductively coupled plasma-optical emission spectrometry(ICP-OES) was developed. The samples were firstly dissolved with organic solvents and then subjected to liquid-liquid extraction, by which the hydrolization of thionyl chloride could lead to the formation of inorganic sulfate, which was then accurately determined by ICP-OES and the content of thionyl chloride residue thus could be calculated. The type of the organic solvent and its volume to sample mass ratio were optimized, and it was found that the sample could be readily dissolved in carbon tetrachloride as the solvent and the ratio of solvent volume to sample mass being 10 (mL:g). Also, the conditions for the extraction procedure were studied, and it was found that when the aqueous phase solution contained 10% (V/V) nitric acid and 2% (V/V) hydrogen peroxide and the shaking time was kept in about 2 min, the full hydrolization of thionyl chloride and the complete oxidation of H2SO3 could be accomplished, as well as a quick separation of the two organic/water phase was realized. The results showed that the limit of detection (LOD, 3s) of the method was 0.22 mg/kg (calculated as S), the relative standard deviation (RSD) was 2.1% for six real sample analysis, and the recoveries of spiked test were 92.7%-104.6%. The established method was finally applied to the analysis of the real samples collected from the purification process of the terephthaloyl chloride production plant and the results were highly in accordance with theoretically predicted value.
2019, 47(3): 415-422
doi: 10.19756/j.issn.0253-3820.181444
Abstract:
准确测定天然地质样品中Li同位素组成是Li同位素地球化学研究的基础。本研究采用AG 50W-X12（200~400目，1.5 mL）阳离子树脂，以0.4和1.0 mol/L HCl作为淋洗介质，建立了适用于不同类型地质样品，且简单、高效的化学分离Li的方法。分离水样和岩石中的Li时，仅需8.5和14.0 mL淋洗液，与前人方法对比（25~190 mL），大大降低了淋洗液使用量，且流程空白信号（（2.4±0.1）mV）与使用的2% HNO3的信号（2.3 mV）几乎一致。在淋洗过程中会发生明显的Li同位素分馏，当Li回收不完全时，测得的δ7Li值相差最高达~50‰，而完全回收Li可以避免该偏差。测定了部分国际标准物质的Li同位素组成：海水δ7Li值为+31.4‰±0.7‰（n=18），安山岩AGV-2为+7.2‰±0.2‰（n=4），玄武岩BCR-2为+3.7‰±0.7‰（n=8），花岗闪长岩GSP-2为-0.10‰±0.18‰（n=4），与已报道的数据吻合，分析精度优于0.8‰，达到国际同类实验室水平。本方法在保证回收率的前提下，树脂和试剂的使用量减少为文献报道使用量的50%，甚至更低，提高了工作效率，并降低了流程空白，可操作性和实用性更强。
准确测定天然地质样品中Li同位素组成是Li同位素地球化学研究的基础。本研究采用AG 50W-X12（200~400目，1.5 mL）阳离子树脂，以0.4和1.0 mol/L HCl作为淋洗介质，建立了适用于不同类型地质样品，且简单、高效的化学分离Li的方法。分离水样和岩石中的Li时，仅需8.5和14.0 mL淋洗液，与前人方法对比（25~190 mL），大大降低了淋洗液使用量，且流程空白信号（（2.4±0.1）mV）与使用的2% HNO3的信号（2.3 mV）几乎一致。在淋洗过程中会发生明显的Li同位素分馏，当Li回收不完全时，测得的δ7Li值相差最高达~50‰，而完全回收Li可以避免该偏差。测定了部分国际标准物质的Li同位素组成：海水δ7Li值为+31.4‰±0.7‰（n=18），安山岩AGV-2为+7.2‰±0.2‰（n=4），玄武岩BCR-2为+3.7‰±0.7‰（n=8），花岗闪长岩GSP-2为-0.10‰±0.18‰（n=4），与已报道的数据吻合，分析精度优于0.8‰，达到国际同类实验室水平。本方法在保证回收率的前提下，树脂和试剂的使用量减少为文献报道使用量的50%，甚至更低，提高了工作效率，并降低了流程空白，可操作性和实用性更强。
2019, 47(3): 423-428
doi: 10.19756/j.issn.0253-3820.181622
Abstract:
By comparing the methods of matrix matching and standard addition and multi-spectral fitting (MSF) for elimination of interference, an analytical method for the determination of trace cobalt in high purity nickel by inductively coupled plasma atomic emission spectrometry (ICP-AES) was established. The optimum parameters of the instrument were determined as follows:RF power of 1350 W, atomizer velocity of 0.5 L/min, observation distance of 15 mm, and peristaltic pump speed of 1.0 mL/min. Three calibration methods, matrix matching, standard addition and MSF, were used to determine the standard addition of pure nickel solution. When the standard addition concentrations were 0.10 and 0.20 mg/L, and nickel concentration was 5 g/L, the three methods all could get good recovery. The linear correlation coefficients were all greater than 0.9996, the recoveries were 95.0%-102.0%, and the RSDs were 2.1%-4.6%. The linear range of MSF method was the best (0.02-0.5 mg/L) and the detection limit was the lowest (0.002 mg/L). When the standard addition concentrations of nickel were 0.02 and 0.06 mg/L and the nickel concentration was 15 g/L, the results showed that only the MSF method could get accurate results with linear correlation coefficient of 0.9999, linear range of 0.02-0.1 mg/L, detection limit of 0.002 mg/L, recoveries of 95.0%-105.0%, and RSDs of 3.9%-4.6%. The MSF method was used to test the actual samples. The analytical results were 0.000154%, which was consistent with the GD-MS method. The RSD was 2.3%. The accuracy and precision of the method were further verified. MSF method is not only strong in anti-interference, simple in operation, economical and practical, but also has high precision, low detection limit. The lower limit of detection (0.0001%) and detection range are superior to the national standard atomic absorption spectrometry (0.001%). It provides an important methodological method for the determination of trace impurities in high-purity samples.
By comparing the methods of matrix matching and standard addition and multi-spectral fitting (MSF) for elimination of interference, an analytical method for the determination of trace cobalt in high purity nickel by inductively coupled plasma atomic emission spectrometry (ICP-AES) was established. The optimum parameters of the instrument were determined as follows:RF power of 1350 W, atomizer velocity of 0.5 L/min, observation distance of 15 mm, and peristaltic pump speed of 1.0 mL/min. Three calibration methods, matrix matching, standard addition and MSF, were used to determine the standard addition of pure nickel solution. When the standard addition concentrations were 0.10 and 0.20 mg/L, and nickel concentration was 5 g/L, the three methods all could get good recovery. The linear correlation coefficients were all greater than 0.9996, the recoveries were 95.0%-102.0%, and the RSDs were 2.1%-4.6%. The linear range of MSF method was the best (0.02-0.5 mg/L) and the detection limit was the lowest (0.002 mg/L). When the standard addition concentrations of nickel were 0.02 and 0.06 mg/L and the nickel concentration was 15 g/L, the results showed that only the MSF method could get accurate results with linear correlation coefficient of 0.9999, linear range of 0.02-0.1 mg/L, detection limit of 0.002 mg/L, recoveries of 95.0%-105.0%, and RSDs of 3.9%-4.6%. The MSF method was used to test the actual samples. The analytical results were 0.000154%, which was consistent with the GD-MS method. The RSD was 2.3%. The accuracy and precision of the method were further verified. MSF method is not only strong in anti-interference, simple in operation, economical and practical, but also has high precision, low detection limit. The lower limit of detection (0.0001%) and detection range are superior to the national standard atomic absorption spectrometry (0.001%). It provides an important methodological method for the determination of trace impurities in high-purity samples.
2019, 47(3): 429-438
doi: 10.19756/j.issn.0253-3820.181575
Abstract:
By regulating collision energy and mass-to-charge ratio, a rapid identification method for uranium-containing compounds from aqueous solutions was established by electrospray ionization tandem mass spectrometry. At high collision energy of 200 V in collision-induced dissociation mode, target ions were bombarded to generate product ions which were subsequently analyzed whether there was mass spectrum peak of[UO2]+ (m/z 269.9), thus identifying the existence of uranium-containing molecules because[UO2]+ was their basic functional group. Based on this method, 16 uranyl citrate and 5 inorganic uranyl speciation were identified in the citric acid-uranyl nitrate solution. Each uranyl group could bind a citrate anion tightly and complex weakly more than one citric acid molecule to form mono uranyl complex. Experiment result showed the following sequence of uranyl citrate complex bond energies:uranyl bond energy > citrate anion-uranyl bond energy > citric acid molecule-uranyl bond energy, and it was also found speciation of double-charged and double-uranyl ions, of which the fragmentation pathways needed further analysis. The method used in here unnecessarily required interpretation of mass spectra or standards of uranium, which would further demonstrate the utility of ESI-MS and its applicability to analyze uranyl-citrate speciation of environmental samples. It improved the identifying ability and efficiency of uranium speciation greatly, which provided reference significance for the study of other heavy metal organic speciation. Meanwhile, U(I) was split from[UO2OH]+ by controlled particle collision, which provided a possible way to separate and purify uranium.
By regulating collision energy and mass-to-charge ratio, a rapid identification method for uranium-containing compounds from aqueous solutions was established by electrospray ionization tandem mass spectrometry. At high collision energy of 200 V in collision-induced dissociation mode, target ions were bombarded to generate product ions which were subsequently analyzed whether there was mass spectrum peak of[UO2]+ (m/z 269.9), thus identifying the existence of uranium-containing molecules because[UO2]+ was their basic functional group. Based on this method, 16 uranyl citrate and 5 inorganic uranyl speciation were identified in the citric acid-uranyl nitrate solution. Each uranyl group could bind a citrate anion tightly and complex weakly more than one citric acid molecule to form mono uranyl complex. Experiment result showed the following sequence of uranyl citrate complex bond energies:uranyl bond energy > citrate anion-uranyl bond energy > citric acid molecule-uranyl bond energy, and it was also found speciation of double-charged and double-uranyl ions, of which the fragmentation pathways needed further analysis. The method used in here unnecessarily required interpretation of mass spectra or standards of uranium, which would further demonstrate the utility of ESI-MS and its applicability to analyze uranyl-citrate speciation of environmental samples. It improved the identifying ability and efficiency of uranium speciation greatly, which provided reference significance for the study of other heavy metal organic speciation. Meanwhile, U(I) was split from[UO2OH]+ by controlled particle collision, which provided a possible way to separate and purify uranium.
2019, 47(3): 439-446
doi: 10.19756/j.issn.0253-3820.181422
Abstract:
To explore the possibility of applying the characteristics of element composition and stable isotopes of Trichiurus haumela sold online for investigation of traceability of geographic origin, the stable isotope ratios (δ13C and δ15N) and multi-element (Na, Mg, K, Ca, Mn, Fe, Cu, Zn, As, Sr) contents of 24 batches of trichiurus haumela in different regions including Lvsi Fishing Ground, Zhoushan Fishing Ground, Qinghai Fishing Ground, and Minnan Fishing Ground were determined by liquid chromatography-isotope mass spectrometry (LC-IRMS) and inductively coupled plasma mass spectrometry (ICP-MS). Based on the differences in their stable isotope ratios and elemental composition, a discriminant model was established based on cluster analysis (CA) and principal component analysis (PCA) to trace the origin of trichiurus haumela sold online in the four regions. Analysis of variance (ANOVA) showed that the stable isotope ratios and elemental composition of trichiurus haumela sold online in each area had obvious regional characteristics, and the contents of the nine elements were significantly different. CA result indicated that the correct discrimination rate of the sample origin was 83.33%. PCA showed that the scattered points of the first three principal components (the cumulative variance contribution rate is 82.16%) were divided into four relatively concentrated areas without any overlap with each other, and could effectively distinguish the origin of trichiurus haumela sold online. In summary, the use of stable isotopes and multi-element detection combined with CA, PCA could effectively trace the origin and discriminate of trichiurus haumela sold online, had certain feasibility and application value.
To explore the possibility of applying the characteristics of element composition and stable isotopes of Trichiurus haumela sold online for investigation of traceability of geographic origin, the stable isotope ratios (δ13C and δ15N) and multi-element (Na, Mg, K, Ca, Mn, Fe, Cu, Zn, As, Sr) contents of 24 batches of trichiurus haumela in different regions including Lvsi Fishing Ground, Zhoushan Fishing Ground, Qinghai Fishing Ground, and Minnan Fishing Ground were determined by liquid chromatography-isotope mass spectrometry (LC-IRMS) and inductively coupled plasma mass spectrometry (ICP-MS). Based on the differences in their stable isotope ratios and elemental composition, a discriminant model was established based on cluster analysis (CA) and principal component analysis (PCA) to trace the origin of trichiurus haumela sold online in the four regions. Analysis of variance (ANOVA) showed that the stable isotope ratios and elemental composition of trichiurus haumela sold online in each area had obvious regional characteristics, and the contents of the nine elements were significantly different. CA result indicated that the correct discrimination rate of the sample origin was 83.33%. PCA showed that the scattered points of the first three principal components (the cumulative variance contribution rate is 82.16%) were divided into four relatively concentrated areas without any overlap with each other, and could effectively distinguish the origin of trichiurus haumela sold online. In summary, the use of stable isotopes and multi-element detection combined with CA, PCA could effectively trace the origin and discriminate of trichiurus haumela sold online, had certain feasibility and application value.
2019, 47(3): 447-454
doi: 10.19756/j.issn.0253-3820.181681
Abstract:
Phenolic compounds are toxic and difficult to be degraded, and can cause serious pollution to the environment. Conventional off-line detection methods for phenolic compounds mostly require complicated and time-consuming pretreatment process. Therefore, it is an urgent need to develop a method for highly sensitive and rapid measurement of phenolic compounds. In this work, a novel toluene enhanced-high pressure photoionization (TE-HPPI) source, based on a vacuum ultraviolet (VUV) lamp filling with krypton (Kr) gas, was developed for rapid detection of phenolic compounds by time-of-flight mass spectrometry (TOFMS). By introducing toluene as the reagent molecule and elevating the ion source pressure, the detection sensitivities for 0.5 μg/L phenol, 3-methylphenol, 2-chlorophenol, 2,4-dichlorophenol and 2,4,6-trichloropenol were improved by 14.8, 2.68, 2.47, 2.33 and 2.30 times, respectively. The ionization process of phenolic compounds was not affected by sample humidity. A dynamic bubbling and purging inlet method was employed to measure phenolic compounds in liquid samples without any pretreatment process. The limits of detection (LODs) of phenol, 3-methylphenol, 2-chlorophenol, 2,4-dichlorophenol and 2,4,6-trichloropenol in gas phase within 1 min were down to 0.24, 1.43, 0.42, 19.8 and 29.1 ng/L, respectively, while the LODs were 4.87, 3.60, 0.21, 1.50 and 4.32 μg/L in solution, respectively. The method was successfully applied for analyzing phenolic compounds in sludge suspension from sewage treatment plants. The capability of high sensitivity, fast analysis, few fragmentation and simple spectrum interpretation have made the TE-HPPI-TOFMS as a promising tool in rapid detection and online monitoring of phenolic pollutants.
Phenolic compounds are toxic and difficult to be degraded, and can cause serious pollution to the environment. Conventional off-line detection methods for phenolic compounds mostly require complicated and time-consuming pretreatment process. Therefore, it is an urgent need to develop a method for highly sensitive and rapid measurement of phenolic compounds. In this work, a novel toluene enhanced-high pressure photoionization (TE-HPPI) source, based on a vacuum ultraviolet (VUV) lamp filling with krypton (Kr) gas, was developed for rapid detection of phenolic compounds by time-of-flight mass spectrometry (TOFMS). By introducing toluene as the reagent molecule and elevating the ion source pressure, the detection sensitivities for 0.5 μg/L phenol, 3-methylphenol, 2-chlorophenol, 2,4-dichlorophenol and 2,4,6-trichloropenol were improved by 14.8, 2.68, 2.47, 2.33 and 2.30 times, respectively. The ionization process of phenolic compounds was not affected by sample humidity. A dynamic bubbling and purging inlet method was employed to measure phenolic compounds in liquid samples without any pretreatment process. The limits of detection (LODs) of phenol, 3-methylphenol, 2-chlorophenol, 2,4-dichlorophenol and 2,4,6-trichloropenol in gas phase within 1 min were down to 0.24, 1.43, 0.42, 19.8 and 29.1 ng/L, respectively, while the LODs were 4.87, 3.60, 0.21, 1.50 and 4.32 μg/L in solution, respectively. The method was successfully applied for analyzing phenolic compounds in sludge suspension from sewage treatment plants. The capability of high sensitivity, fast analysis, few fragmentation and simple spectrum interpretation have made the TE-HPPI-TOFMS as a promising tool in rapid detection and online monitoring of phenolic pollutants.
2019, 47(3): 455-462
doi: 10.19756/j.issn.0253-3820.181299
Abstract:
A simple and novel sample pretreatment method for determination of eight kinds of mycotoxin in juice samples has been developed using acid-assisted dispersive liquid-liquid microextraction coupled with high performance liquid chromatography-tandem mass spectrometry. The factors effecting extraction efficiency were investigated including the type and volume of extraction solvent, the volume of dispersive solvent and pH of the equilibrium system. Under the optimum extraction conditions including 60 μL of trichloroaniline as extraction solvent, 1500 μL of hydrochloric acid solution as dispersive solvent and pH 5 as the acidity of equilibrium system, the method showed a good linearity for these mycotoxins within the concentration range from 1 to 500 μg/L with correlation coefficients higher than 0.994. The detection limits were 0.15-17.71 ng/L, 0.09-7.08 ng/L and 0.40-14.29 ng/L in fruit juice of mango, pineapple and dragon, respectively. The average recoveries of eight kinds of mycotoxins ranged from 75.6% to 110.0% at three spiked concentrations of 0.2 μg/L, 1.0 μg/L and 10.0 μg/L, with the relative standard deviation of lower than 15.5%. The proposed method is simple, fast with less consumption of organic solvent, and has high sensitivity and repeatability, which is suitable for the detection of mycotoxins residues in fruit juice.
A simple and novel sample pretreatment method for determination of eight kinds of mycotoxin in juice samples has been developed using acid-assisted dispersive liquid-liquid microextraction coupled with high performance liquid chromatography-tandem mass spectrometry. The factors effecting extraction efficiency were investigated including the type and volume of extraction solvent, the volume of dispersive solvent and pH of the equilibrium system. Under the optimum extraction conditions including 60 μL of trichloroaniline as extraction solvent, 1500 μL of hydrochloric acid solution as dispersive solvent and pH 5 as the acidity of equilibrium system, the method showed a good linearity for these mycotoxins within the concentration range from 1 to 500 μg/L with correlation coefficients higher than 0.994. The detection limits were 0.15-17.71 ng/L, 0.09-7.08 ng/L and 0.40-14.29 ng/L in fruit juice of mango, pineapple and dragon, respectively. The average recoveries of eight kinds of mycotoxins ranged from 75.6% to 110.0% at three spiked concentrations of 0.2 μg/L, 1.0 μg/L and 10.0 μg/L, with the relative standard deviation of lower than 15.5%. The proposed method is simple, fast with less consumption of organic solvent, and has high sensitivity and repeatability, which is suitable for the detection of mycotoxins residues in fruit juice.
2019, 47(3): 463-470
doi: 10.19756/j.issn.0253-3820.181486
Abstract:
A method of stir bar sorptive extraction (SBSE) based on monohydroxyl cucurbit7 uril (Q7-OH)-liquid desorption (LD)-high performance liquid chromatography (HPLC)-ultraviolet detection was developed for measurement of three residual estrogens (bisphenol A, estradiol and diethylstillbestrol) from animal-derived foods (pork and chicken samples). The hydroxyl polydimethylsiloxane (PDMS-OH)/Q7-OH-coated stir bar was conducted by the sol-gel technique with the synthesized Q7-OH as a selective stationary phase. The innovative SBSE exhibited a rough and porous surface structure, a good preparation reproducibility (RSD ≤ 8.4%) and a long lifespan. Extraction mechanism indicated that the increase of extraction efficiency was attributed to the excellent molecular recognition of Q7 towards analytes. Under the optimal experimental conditions, the limits of detection of the developed PDMS/Q7-OH SBSE-LD-HPLC-UV method were 0.05-0.56 μg/L for the target estrogens with enrichment factors of 19-25 folds, the dynamic linear range was 0.2-5000 μg/L, and the RSDs were in the range of 3.9%-7.5% (n=5, C=100 μg/L). The mean recoveries (n=3) at three different concentration levels were 72.7%-109.2%. The developed method was simple, sensitive, and selective, and was successfully applied to the analysis of estrogens in animal-derived foods (pork and chicken samples).
A method of stir bar sorptive extraction (SBSE) based on monohydroxyl cucurbit7 uril (Q7-OH)-liquid desorption (LD)-high performance liquid chromatography (HPLC)-ultraviolet detection was developed for measurement of three residual estrogens (bisphenol A, estradiol and diethylstillbestrol) from animal-derived foods (pork and chicken samples). The hydroxyl polydimethylsiloxane (PDMS-OH)/Q7-OH-coated stir bar was conducted by the sol-gel technique with the synthesized Q7-OH as a selective stationary phase. The innovative SBSE exhibited a rough and porous surface structure, a good preparation reproducibility (RSD ≤ 8.4%) and a long lifespan. Extraction mechanism indicated that the increase of extraction efficiency was attributed to the excellent molecular recognition of Q7 towards analytes. Under the optimal experimental conditions, the limits of detection of the developed PDMS/Q7-OH SBSE-LD-HPLC-UV method were 0.05-0.56 μg/L for the target estrogens with enrichment factors of 19-25 folds, the dynamic linear range was 0.2-5000 μg/L, and the RSDs were in the range of 3.9%-7.5% (n=5, C=100 μg/L). The mean recoveries (n=3) at three different concentration levels were 72.7%-109.2%. The developed method was simple, sensitive, and selective, and was successfully applied to the analysis of estrogens in animal-derived foods (pork and chicken samples).
2019, 47(3): 471-478
doi: 10.19756/j.issn.0253-3820.181576
Abstract:
Chloramphenicol monodispersed restricted access media-molecularly imprinted polymers (CAP-MRAM-MIPs) were prepared by surface-initiated atom transfer radical polymerization (SI-ATRP) with monodisperse crosslinked poly(Glycidyl methacrylate-co-ethylenedimethacrlate) (PGMA/EDMA) microspheres as solid phase matrix, and chloramphenicol (CAP) as template molecules. The imprinted polymers were characterized by Fourier transform infrared (FT-IR) spectrum, scanning electron microscope (SEM), thermogravimetric (TGA), element analysis and contact angle method. Furthermore, the results of specific surface area, pore volume and pore size showed that the pore size and pore volume of CAP-MRAM-MIPs were larger than those of the chloramphenicol monodisperse restricted access media-molecularly non-imprinted polymers (CAP-MRAM-NIPs). The exclusion of CAP-MRAM-MIPs to bovine serum albumin (BSA) was 97.2%. The maximum absorbed amounts, distribution coefficient (Kd) and imprinting factors (α) of CAP were 56.7 mg/g, 34.42 mL/g and 2.25 mg/g. By combining with high performance liquid chromatographic (HPLC) analysis, the CAP-MRAM-MIPs were applied to the separation and enrichment of CAP in milk samples with recoveries of 93.5%-102.6%.
Chloramphenicol monodispersed restricted access media-molecularly imprinted polymers (CAP-MRAM-MIPs) were prepared by surface-initiated atom transfer radical polymerization (SI-ATRP) with monodisperse crosslinked poly(Glycidyl methacrylate-co-ethylenedimethacrlate) (PGMA/EDMA) microspheres as solid phase matrix, and chloramphenicol (CAP) as template molecules. The imprinted polymers were characterized by Fourier transform infrared (FT-IR) spectrum, scanning electron microscope (SEM), thermogravimetric (TGA), element analysis and contact angle method. Furthermore, the results of specific surface area, pore volume and pore size showed that the pore size and pore volume of CAP-MRAM-MIPs were larger than those of the chloramphenicol monodisperse restricted access media-molecularly non-imprinted polymers (CAP-MRAM-NIPs). The exclusion of CAP-MRAM-MIPs to bovine serum albumin (BSA) was 97.2%. The maximum absorbed amounts, distribution coefficient (Kd) and imprinting factors (α) of CAP were 56.7 mg/g, 34.42 mL/g and 2.25 mg/g. By combining with high performance liquid chromatographic (HPLC) analysis, the CAP-MRAM-MIPs were applied to the separation and enrichment of CAP in milk samples with recoveries of 93.5%-102.6%.
