最新刊期
卷 41 ， 期 12 ， 2022
- 摘要：A gas chromatography－tandem mass spectrometry with online catalysis was established for the determination of polychlorinated biphenyls（PCBs），polychlorinated naphthalene（PCNs），short-chain chlorinated paraffins（SCCPs） and medium-chain chlorinated paraffins（MSCCPs） in imported oil-bearing metal raw materials．The pretreatment conditions for solid phase extraction（SPE） were investigated，and the effects of catalyst preparation，catalytic temperature，hydrogen flow rate and chlorination degree on the catalytic efficiency were investigated．And the catalytic conditions were optimized by response surface method．The samples were online dechlorinated and hydrogenated by self-made catalytic device．The target compounds were converted into n-alkanes and aromatic hydrocarbons with unchanged carbon framework after catalysis，and detected in multi-reaction monitoring mode．The calibration curves for ten reduction products were linear in the range of 0.02－1.00 μg/mL．The limits of quantitation were 0.26－5.33 μg/kg．The recoveries ranged from 87.2% to 111%，with the relative standard deviations（RSDs） not more than 7.1%．The method is simple，accurate and reliable，and it could achieve a low detection limit with no need of GC－CI－MS or HRMS．Therefore，it is suitable for the determination of chlorine pollutants in imported oil-bearing metal raw materials.关键词：online catalysis;hydrodechlorination;gas chromatography－tandem mass spectrometry;chlorine pollutants;oil-bearing metal raw materials
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发布时间：2023-01-04 - 摘要：High throughput mass spectrometry combined with label-free quantitative technique was used to identify the milk fat globule membrane（MFGM） proteins of goat milk at different lactation stages．331 and 252 MFGM proteins were quantified in goat milk colostrum and mature milk，respectively，of which 164 proteins were co-expressed．The identified MFGM proteins were analyzed by univariate and multivariate analysis，and the partial least squares discriminant analysis model was established. Taking 2，0.05 and 1.2 as the thresholds of fold change，significant difference and variable projection importance analysis value，the differential markers in colostrum and mature milk were screened．Bioinformatics analysis showed that the identified protein markers mainly involved in inflammatory process，integrin signaling pathway and galactose metabolism．The results were of great significance to facilitate people’s in-depth understanding of goat milk protein，upgrading the nutritional improvement of milk and its products and the production of breast milk substitutes.关键词：goat milk;milk fat globule membrane（MFGM） proteins;ultrahigh performance liquid chromatography－quadrupole－orbitrap mass spectrometry;proteomics
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发布时间：2023-01-04 - 摘要：An analytical method was developed for qualitative non-targeted screening of 79 drug residues in pork by ultra-performance liquid chromatography quadrupole time-of-flight mass spectrometry（UPLC－Q－TOF MS）．The samples were firstly extracted with 0.5%（by volume） formic acid－acetonitrile，then extracted with methanol．After centrifugation，the supernatant was cleaned up with FAVEX－NM50 rapid column of veterinary drug residues，then separated on an Acquity UPLC BEH HSS－C18 column（2.1 mm × 150 mm，1.7 μm），ionized in ESI+ mode，and detected in MSE mode．The calibration curves for 79 drugs had good linearity in the linear range with correlation coefficients（r2） not less than 0.99. The limits of detection and the limits of quantitation were in the ranges of 0.05－10 μg/kg and 0.10－20 μg/kg，respectively．The simulated positive samples and commercial pork samples were screened using the self-built mass spectrometry database．Meanwhile，the commercial pork samples were detected by high sensitivity Xevo TQ－S tandem quadrupole mass spectrometry in multiple reaction monitoring（MRM） mode．Method validation showed that the established method was efficient，rapid and high throughput，which is suitable for the screening and identification of drug residues in pork.关键词：ultra-performance liquid chromatography quadrupole time-of-flight mass spectrometry （UPLC－Q－TOF MS）;non-targeted screening;high throughput;drug residues;pork
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发布时间：2023-01-04 - 摘要：An ultra-performance liquid chromatography－tandem mass spectrometry（UPLC－MS/MS） with 6-aminoquinolyl-N-hydroxysuccinimidyl carbamate（AQC） pre-column derivation was established for the determination of 23 endogenous amino acids and taurine in honey．The honey samples were extracted with water and derived with AQC，then separated on an AccQ－Tag Ultra C18 column（2.1 mm × 100 mm，1.7 µm） by gradient elution with acetonitrile－10 mmol/L ammonium formate as the mobile phase，and finally analyzed by mass spectrometry in positive ion multiple reaction monitoring mode and quantified by internal standard method．The calibration curves for amino acids and taurine showed good linearity in their respective concentration ranges，with correlation coefficients（r） not less than 0.993 0．The limits of detection（LODs） and the limits of quantitation（LOQs） were in the range of 0.03－0.15 μmol/L and 0.1－0.5 μmol/L，respectively．The average recoveries ranged from 90.5% to 109%，with relative standard deviations of 1.2%－4.7%．Through analyses on 39 batches of real honey，39 batches of adulterated honey and 10 batches of syrup，it was found that the types and content of target compounds in different honey sources differed largely．The contents of amino acids and taurine in adulterated honey were significantly lower than that in real honey，and no target compounds were detected in syrup．This method was simple，sensitive and accurate，and it could be used for the determination of free amino acids and taurine in honey，providing a technical support for the quality evaluation and authenticity identification.关键词：honey;amino acids;taurine;AQC derivation;ultra-performance liquid chromatography－tandem mass spectrometry
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发布时间：2023-01-04 - 摘要：An ultra-performance liquid chromatography－tandem mass spectrometry（UPLC－MS/MS） was established for the determination of 4 antibiotics in children’s cosmetics．The cosmetic samples were extracted with 70% acetonitrile－water solution，and then purified with a SCX column．The target analytes were separated on a Waters ACQUITY BEH C18（2.1 mm × 100 mm，2.5 μm） column using 0.1% formic acid solution and acetonitrile as mobile phases．The analysis was performed under multiple reaction monitoring（MRM） mode．Results showed that there were good linear relationships for 4 antibiotics in the respective concentration ranges with their correlation coefficients（r） of 0.999．The limits of detection（LODs） and limits of quantitation（LOQs） of the method were in the range of 0.005－0.250 μg/g and 0.010－0.500 μg/g，respectively. Average recoveries for the 4 antibiotics in 3 kinds of samples at 3 spiked levels ranged from 89.3% to 113%，with relative standard deviations（RSDs，n = 6） of 0.90%－7.2%．The method is effective，accurate and specific，and it could be used for the determination of 4 antibiotics in children’s cosmetics.关键词：antibiotic;children’s cosmetics;ultra-performance liquid chromatography－tandem mass spectrometry（UPLC－MS/MS）;purification
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发布时间：2023-01-04 - 摘要：An ultra performance liquid chromatography－tandem mass spectrometry（UPLC－MS/MS） with solid phase extraction was established for the simultaneous determination of 37 kinds of prohibited veterinary drug residues，i.e．sulfonamides，aminools，nitroimidazoles，benzimidazoles and antiviral classes in aquacultural “non-pharmaceutical” inputs．The samples were extracted with 80% acetonitrile aqueous solution containing 0.2% formic acid and chelated with Mcllvaine－Na2EDTA buffer，then ultrasonically extracted．The residues contents were separated on a C18 chromatographic column，then determined by UPLC－MS/MS with electrospray ion source in positive and negative ion mode under multiple reaction monitoring mode．The quantitative information was obtained by matrix-added calibration with external standard．The correlation coefficients of calibration curves for 37 banned veterinary drugs were not less than 0.991．The limits of detection and quantitation were in the range of 0.156－1.94 μg/kg and 0.520－6.47 μg/kg，respectively．The spiked recoveries of the method ranged from 71.6% to 119%，with the relative standard deviations（RSDs） of 1.2%－15%．The method is rapid，accurate and sensitive，and it could be used for the rapid and accurate screening and detection of 37 kinds of prohibited veterinary drug residues in aquacultural “non-pharmaceutical” inputs.关键词：solid phase extraction;ultra performance liquid chromatography－tandem mass spectrometry （UPLC－MS/MS）;“non-pharmaceutical” inputs;veterinary drug residue
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发布时间：2023-01-04 - 摘要：A headspace/gas chromatography－tandem mass spectrometry（HS/GC－MS/MS） was established for the screening of 35 volatile allergic fragrances in different new mosquito repellent products．The new mosquito repellent products included mosquito repellent stickers，mosquito repellent buckles and mosquito repellent bracelets，etc．35 substances were separated by a medium polarity Agilent DB－17MS column and detected with electron impact ion source（EI） under multiple reactions monitoring（MRM） mode．Two different headspace equilibrium temperatures of 40 ℃ and 100 ℃ were selected．The screening results for 37 new mosquito repellent products showed significant differences at different temperatures．A total of 14 volatile allergic fragrances were detected at 40 ℃，including α-pinene，β-pinene，D-limonene，benzaldehyde，terpinolene，linalool，DL-menthol，D-camphor，linalyl acetate，citronellol，methyl salicylate，citral，β-caryophyllene and cinnamaldehyde．In addition，another 12 allergic fragrances at 100 ℃ were found，including terpineol，geraniol，carvone，4-methoxyphenol，4-tert-butylphenol，trans-anethole，eugenol，benzalacetone，lily aldehyde，farnesol，α-amylcinnamyl alcohol and benzyl benzoate．Taking the mosquito repellent stickers and mosquito repellent buckles for children for examples，the response intensities of the target compounds at different headspace temperatures were semi-quantitatively determined．The results showed that the response intensities for the 8 volatile allergic fragrances at 40 ℃ were less than those at 100 ℃．37 samples were semi-quantitatively analyzed at the equilibrium temperature of 40 ℃．The results indicated that 9 volatile allergic fragrances，i.e．α-pinene，β-pinene，D-limonene，benzaldehyde，terpinolene，linalool，DL-menthol，D-camphor and methyl salicylate were detected in most samples，in which the maximum response intensities for α-pinene and D-limonene were more than 106．The volatilization patterns for volatile allergic fragrances in new mosquito repellent products were also studied at 40 ℃．The contents of the mosquito repellent stickers and mosquito repellent buckles kept at 40 ℃ for different times were determined，of which 5 volatile allergic fragrances，including α-pinene，β-pinene，D-limonene，DL-menthol and D-camphor with high detection rates and strong response intensities were investigated. Among the 5 analytes，α-pinene，β-pinene and D-limonene showed significant downward trends from 0 hour to 12 hours，which decreased to 20%－21%．The response intensities for both DL-menthol and D-camphor were still more than 40% of those at the beginning after 72 hours．This study provides a technical reference for the subsequent quantitative analysis and risk assessment of multiple allergic fragrances in mosquito repellent products.关键词：headspace;gas chromatography－tandem mass spectrometry（GC－MS/MS）;mosquito repellent product;allergic fragrance;volatilization patterns
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发布时间：2023-01-04 - 摘要：Gas chromatography system was utilized to identify the main degradation products and structures of dicofol．Its degradation behaviors in the inlet and organic solvents were investigatied and the measures to minimize the degradation effects on the analysis were proposed．The results showed that the main degradation products of dicofol，in addition to the reported 4，4'-DBP，were obtained through the de-chlorination pathway．Generally，dicofol is stable when the inlet temperature is lower than 260 ℃，and it is stable in toluene but completely degrade to 4，4'-DBP in acetone and acetonitrile．Meanwhule，anhydrous solvent could slow down the degradation process．In ethyl acetate，dicofol could be partly degraded by dechlorination．The addition of halides to the solvent could prohibit the dechlorination．Dicofol，4，4'-DBP and degraded products were used to determine the residual amount of dicofol in the actual sample matrix by measuring the sum of the three peak areas due to the uncertainty of the sample matrix polarity．The average recoveries of this method for three matrixes at 0.01，0.05 and 0.1 mg/kg spiked levels ranged from 72.5% to 110%，with the relative standard deviations（RSDs，n = 6） of 5.1%－10%．This study provides an experimental basis for accurate，qualitative and quantitative detection of dicofol，which is of a certain reference value for exploring the degradation of compounds with the smilar structure.关键词：dicofol;degradation;the temperature of the inlet;solvent;quantification;gas chromatography system
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发布时间：2023-01-04 - 摘要：A high performance liquid chromatography－tandem mass spectrometry（HPLC－MS/MS） was developed for the simultaneous determination of 17 neonicotinoid pesticides and their metabolites in baby fruit and vegetable rice flour．After moistened with water，the samples were added anhydrous magnesium sulfate（MgSO4），then extracted with acetonitrile solution containing 1%（volume fraction） formic acid，followed by QuEChERS purification．The final extracts were dried under nitrogen，and the residues were dissolved in water－acetonitrile containing 0.1% formic acid（4∶1，volume ratio），then separated on an Acquity BEH C18（2.1 mm × 100 mm，1.7 μm） column by gradient elution with water containing 0.1% formic acid and acetonitrile as mobile phases．The analytes were finally detected by HPLC－MS/MS in positive electrospray ionization（ESI+） mode under multiple reaction monitoring（MRM） mode，and quantified by the external standard calibration curve method．Under the optimal conditions，17 analytes were well separated within 10 min．The calibration curves for 17 analytes were linear in the respective mass concentration ranges with their correlation coefficients（r） larger than 0.995 4．The limits of detection（LODs） and limits of quantitation（LOQs） were in the range of 0.02－0.15 μg/kg and 0.06－0.50 μg/kg，respectively．The average recoveries for 17 analytes in baby fruit rice flour samples at three spiked levels of LOQ level，2.0 μg/kg and 10.0 μg/kg ranged from 62.5% to 103%，with relative standard deviations（RSDs） of 3.5%－17%，while the average recoveries for vegetable rice flour samples at three spiked levels ranged from 66.4% to 108%，with RSDs of 4.3%－13%．The established method was applied to the detection of 17 neonicotinoid pesticides and their metabolites in baby fruit and vegetable rice flour samples by random sampling principle，and acetamiprid was detected in one of the vegetable rice flour samples with content of 7.4 µg/kg．The method was sensitive，accurate，convenient and reliable，and it could meet the requirements for simultaneous detection of 17 neonicotinoid pesticides and their metabolites in baby fruit and vegetable rice flour.关键词：baby rice flour;high performance liquid chromatography－tandem mass spectrometry（HPLC－MS/MS）;neonicotinoid pesticides;metabolites
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发布时间：2023-01-04 - 摘要：A high performance liquid chromatography－tandem mass spectrometry（HPLC－MS/MS） was established for the rapid analysis of 11 anabolic androgenic steroids，i.e．testosterone，17-methyltestosterone，boldenone，metandienone，androstenedione，dehydroepiandrosterone，nandrolone，nandrolone 17-propionate，stanozolol，melengestrol，progesterone in compound feeds．The samples were extracted with acetonitrile，then purified with PSA，and finally determined on the machine．The separation of target compounds was performed on an Phenomenex C18（100 mm × 2.1 mm，2.6 μm） by gradient elution，using 0.01% formic acid－acetonitrile system as mobile phase．The 11 anabolic androgenic steroids were detected in positive ESI mode under multiple reaction monitoring（MRM） mode，and quantified by the isotope internal standard method．The results showed that the linear ranges for 11 anabolic androgenic steroids were 1－100 ng/mL，and the correlation coefficients were all 0.999．The limits of detection and the limits of quantitation were 20 μg/kg and 50 μg/kg，respectively．The recoveries for 11 anabolic androgenic steroids in chicken compound feed ranged from 94.5% to 111%，with intra-day relative standard deviations（intra-RSDs） and inter-day RSDs（inter-RSDs） both not more than 13%，while the recoveries for the analytes in pig compound feed ranged from 90.1% to 109%，with intra-RSDs and inter-day RSDs not more than 9.0% and 8.8%，respectively．Testosterone and boldenone were detected in actual samples with the contents of 9.09－14.68 mg/kg and 1.22－1.84 mg/kg，respectively．This method could realize the comprehensive，simple and accurate detection of anabolic androgenic steroids in compound feeds，and provide technical support for the regulation of anabolic androgenic steroids abuse in compound feeds in the future.关键词：anabolic androgenic steroids;high performance liquid chromatography－tandem mass spectrometry;compound feed;internal standard method
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发布时间：2023-01-04
Special Column for DRE Thesis Competition
- 摘要：A biosensing platform for the detection of NF－κB p50 was constructed，based on an in situ nanozyme with adjustable catalytic activity．The in situ nanozyme was obtained by combining K4Fe（CN）6 onto the surface of PbTiO3．Generally，the attachment of deoxyribonucleoside 5'-monophosphate（dNMP） onto the PbTiO3 surface may prevent the spontaneous formation of nanozyme on its surface，while in the presence of NF－κB p50，dNMP is hardly to be generated，which allows K4Fe（CN）6 combining smoothly to the surface of PbTiO3，and a spontaneously formed nanozyme on PbTiO3 surface catalyzes TMB oxidation for the quantitative detection of NF－κB p50．The results showed that the detection linear range of this method for NF－κB p50 was 3.0 pmol/L－10 nmol/L，while the limits of detection（S/N = 3） was 1.2 pmol/L．The spiked recoveries for real samples ranged from 99.1% to 102%，with relative standard deviations not more than 5.3%．This method provides a new strategy in label-free，immobilization-free mode for the detection of NF－κB p50 with amplified signal，which not only has high sensitivity，good selectivity and simple operation，but also has an application potential in the detection of actual samples.关键词：nanozyme;biosensing;PbTiO3;NF－κB p50
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发布时间：2023-01-04 - 摘要：An improved QuEChERS/high performance liqiud chromatography－tandem mass spectrometry（HPLC－MS/MS） was established for the determination of 50 common pesticide residues in golden siraitia grosvenoriis．After extracted with water－1%（volume fraction） acetic acid acetonitrile，the samples were purified with a combined adsorbent of 900 mg MgSO4，450 mg PSA，300 mg C18 and 50 mg GCB．Analytes were separated on Agilent Poroshell 120 EC－C18 column（150 mm × 3.0 mm，2.7 μm），using 0.05% formic acid solution（containing 10 mmol/L ammonium formate） and 95% methanol（containing 10 mmol/L ammonium formate and 0.05% formic acid） as mobile phases．Electrospray ionization source was applied in positive and negative ionization（ESI+ and ESI-） mode under multiple reaction monitoring（MRM） mode．Meanwhile，the external standard method was employed to obtain the matrix-matched calibration curve for quantitation．Results showed that there existed good linear relationships for 50 pesticides in the respective concentration ranges，with their correlation coefficients（r） larger than 0.99．The limits of quantitation（LOQs） were 0.01－0.02 mg/kg．The average recoveries at four spiked levels of 2 LOQ，5 LOQ，20 LOQ and 40 LOQ ranged from 60.7% to 115%，with relative standard deviations（RSDs） less than 15% for over 95% pesticides，which met with the requirements for trace analysis．This method is convenient and reliable，and it could be applied to the determination of multi-pesticide residues in golden siraitia grosvenoriis.关键词：golden siraitia grosvenoriis;pesticide residues;QuEChERS;high performance liqiud chromatography－tandem mass spectrometry（HPLC－MS/MS）
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发布时间：2023-01-04 - 摘要：In this work，a covalent organic framework（COF） material TpBD-（NO2）2 was firstly synthesized by solvothermal method，which was then reduced to TpBD-（NH2）2，and finally，a chiral COF material TpBD-（NH2）2-D-（－）-α-phenylglycine was obtained by chirally modifying the TpBD-（NH2）2 with D-（－）-α-phenylglycine．Three COF materials，i.e．TpBD-（NO2）2，TpBD-（NH2）2 and TpBD-（NH2）2-D-（－）-α-phenylglycine were characterized，and a chiral stationary phase of TpBD-（NH2）2-D-（－）-α-phenylglycine was prepared by “net-wrap method”．In order to investigate the separation performance of the stationary phase，it was used to prepare a chiral column for high performance liquid chromatography（HPLC），n-hexane－isopropanol（9∶1，by volume） and methanol－water（9∶1，by volume） were used as mobile phases．13 chiral compounds and 5 benzene positional isomers were separated on this column with good reproducibility．The experiment showed that the separation effect of TpBD-（NH2）2-D-（－）-α-phenylglycine chromatographic column was excellent. It was of a certain research significance to use the chiral COF material TpBD-（NH2）2-D-（－）-α-phenylglycine as HPLC stationary phase for the separation of chiral substances and benzene isomers.关键词：covalent organic framework materials;chiral stationary phase;high performance liquid chromatography;chiral separation
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发布时间：2023-01-04 - 摘要：Based on that the current derivative method for picric acid（TNP） using sodium hypochlorite may result in possible false positive in forensic science identification，a gas chromatography－triple quadrupole mass spectrometry（GC－TQMS） with TNP methylation derivatization method was established for the highly sensitive detection of TNP in this paper．TNP was converted into 2，4，6-trinitroanisole（TNA） via a methylation reaction using trimethyl orthoformate（TMOF） as reagent．Under the optimized methylation derivatization conditions，sample solution was firstly dehydrated and put into a liner pipe，then 100 μL of TMOF were added．The mixture was heating at 95 ℃ for 70 min，and the reactant was analyzed after cooling down and being filtered．The detection effects of GC－TQMS in EI mode and NCI mode were compared．The limits of detection were 1.33 μg/L and 5.02 μg/L in EI and NCI mode，respectively．The detection performance of this method for the mixed organic explosives in soil was also investigated．Five kinds of organic explosives were successfully detected．The spiked recoveries for soil sample were 84.0%，with a relative standard deviation（RSD） of 4.6%．Results showed that the four common nitroaromatic organic explosives investigated had no interference with this method. The method is simple，rapid，sensitive and selective，and it offers a considerable improvement in identifying the picric acid in explosive mixtures，which meets the needs of forensic science identification and could be used for the detection of trace TNP in actual cases.关键词：picric acid;organic explosives;methylation derivatization;gas chromatography-triple quadrupole mass spectrometry
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发布时间：2023-01-04 - 摘要：A platinum nanoparticles modified glassy carbon electrode（Pt NPs/GCE） was fabricated by electrochemical alloy-dealloying method for the determination of oxalic acid（OA） in urine．The Pt－Bi alloy particles were electrochemically deposited on the electrode surface at -0.4 V in HClO4 solution containing Bi（NO3）3，K2PtCl4 and EDTA．Then Bi was electrochemically dissolved from the alloy at 1.2 V in HClO4，and Pt NPs/GCE was obtained. The composition and morphology of the modifier on the electrode surface were characterized by SEM and EDS techniques．Moreover，the electrochemical behavior of OA on this electrode was studied carefully based on the investigation of preparation conditions of the electrode．The results showed that the electrochemical behavior of OA on this electrode was a diffusion-controlled irreversible oxidation process．Benefiting from porous Pt NPs after electrochemical dealloying，this electrode had a larger active area，and thus had a high electrocatalytic activity for the oxidation of OA．The results of optimizing the electrode preparation showed that the modified electrode exhibited an excellent analytical performance for OA when the deposition solution was 1.0 mmol/L K2PtCl6 + 3.0 mmol/L Bi（NO3）3 + 3.0 mmol/L EDTA + 0.10 mol/L HClO4，the electrochemical alloy time was 500 s（-0.4 V），and the dealloying time was 1 000 s（1.2 V）．The linear ranges of amperometry determination for OA at 1.05 V in 0.10 mol/L HClO4 were 2.0 × 10-7－4.9 × 10-4 mol/L and 4.9 × 10-4－6.3 × 10-3 mol/L，with correlation coefficients（r2） of 0.999 1 and 0.998 2，respectively．The detection limit and sensitivity of the method for OA were 2.7 × 10-8 mol/L（3sb） and 83 μA/（mmol·L-1），respectively．Compared with other electrochemical sensors，this electrode had the characteristics of high sensitivity，wide linear range，as well as simple preparation．The electrode was applied to the determination of OA in urine with spiked recoveries of 94.6%－102% and RSDs of 2.2%－4.7%.关键词：electrochemical alloy－dealloying;platinum nanoparticles;modified electrode;oxalic acid（OA）
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发布时间：2023-01-04 - 摘要：Recently developed methane clumped isotope techniques provide fresh and novel insights into methane production and transformation，which have been unobtainable through other techniques such as traditional stable isotope．Methane clumped isotope techniques have the advantages of high resolution and low detection limit．13CH3D and 12CH2D2 have their unique chemical and physical properties recording information on methane isotopic equilibrium states．The measuring methods for paired clumped isotopologues have just been established in China，and the precision of δ12CH2D2 need to be further improved．Based on the first high-resolution gas stable isotope mass spectrometer（HR－IRMS） in China，the measuring method for 12CH2D2 was optimized by balancing the resolution and sensitivity of the instrument．The ［12CH2D2+］ intensity was effectively improved．The analysis precision was successfully improved to 1.29‰ by using H2O+ peak simulation calculation for the contribution of adjacent 13CH3D and 13CH5 peaks to the total background.关键词：methane;clumped isotope;high-resolution gas stable isotope ratio mass spectrometer（HR－IRMS）;precision
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发布时间：2023-01-04
Scientific Papers
- 摘要：Magnetic lateral flow assay（MLFA） is a rapid detection technique using magnetic nanomaterials as functional materials and lateral flow test strips as the analytical platform．It preserves many advantages of traditional lateral flow assay，such as easy operation，fast and real time analysis and low cost．Moreover，the sensitivity and accuracy of lateral flow assay could be further improved by combining with functionalized magnetic nanomaterials，mainly due to the capability of magnetically separating and enriching target analytes from complex matrixes．As a result，MLFA exhibits good performance and great potentials in rapid detection of many fields including food quality and safety．The development of MLFA for food safety in the last five years is mainly emphasized in this review．Different types of magnetic nanomaterials and the principles of MLFA are introduced．Based on various targets，the recent progresses in MLFA detection of foodborne bacteria and hazardous small molecules such as mycotoxins and veterinary drugs are summarized，respectively．In the end，the current stage and future development of MLFA technique are also discussed.关键词：magnetic lateral flow assay;food safety;rapid detection techniques;magnetic nanomaterials;immuno-chromatography assay;foodborne pathogens;mycotoxins;veterinary drug residues
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发布时间：2023-01-04
Review
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