最新刊期
卷 43 ， 期 6 ， 2024
- 摘要：To address the problem of residues of trimethoprim（TMP） and florfenicol（FF） used in combination with food of animal origin，a latex microsphere lateral flow immunochromatographic assay（LMs-LFIA） for the simultaneous detection of trimethoprim and florfenicol in chicken and pork samples using latex microspheres as tracer signal probes was established. Based on the specific monoclonal antibodies 7E6 and SF15，a stepwise optimization strategy investigated the effects of probe preparation conditions，test strip working buffer，and sample pad treatment system on the performance of LMs-LFIA. The results showed that under the optimal conditions，the established LMs-LFIA visualized the detection limits of trimethoprim and florfenicol in chicken and pork samples at 8 ng/g and 12 ng/g，respectively，with a detection time of 8 min. There was no obvious crossover between trimethoprim and florfenicol's structural and functional analogs，indicating good specificity. The established method was used for blind detection of chicken and pork samples，and the results were in agreement with those obtained by the UPLC-MS/MS instrumental confirmatory method. Therefore，the method is suitable for the simultaneous detection of trimethoprim and florfenicol residues in livestock and poultry tissue samples.关键词：trimethoprim;florfenicol;monoclonal antibodies;latex microspheres lateral flow immunochromatographic assay（LMs-LFIA）;rapid detection
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发布时间：2024-06-11 - 摘要：An ultra-performance liquid chromatography-quadrupole-time-of-flight tandem mass spectrometry（UPLC-Q-TOF-MS/MS） method was applied to identify chemical constituents rapidly of Huangqin Qingre Chubi Capsule （HQC）. The gradient elution was performed on a Water ACQUITY UPLC BEH C18（2.1 mm×100 mm，1.7 μm） with 0.1% formic acid-acetonitrile as mobile phases. Positive and negative ion ESI modes were used simultaneously to collect base peak chromatograms of HQC. In addition，a self building library of HQC was established and targeted sceening based on UNIFI platform.The chemical constituents were identified and confirmed by analyzing the precise molecular weight of the compound，secondary fragment ion information，reference products and literature data. A total of 82 chemical constituents were tentatively identified，including 37 flavonoids，11 organic acids，14 terpenoids，7 glycosides，5 amino acids and 8 other compounds. HQC is mainly composed of flavonoids. The method of UPLC-Q-TOF-MS/MS combined with UNIFI can rapidly identify the chemical components of HQC.关键词：Huangqin Qingre Chubi capsule;UPLC-Q-TOF-MS/MS;UNIFI analysis platform;chemical composition;rheumatoid arthritis
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发布时间：2024-06-11 - 摘要：A high performance liquid chromatography（HPLC） characteristic chromatogram analysis method of Eupatorium fortunei（E. fortunei） was established to differentiate it from its adulterants. Ultrahigh performance liquid chromatography-Q-exactive orbitrap mass spectrometry（UHPLC-Q-Exactive Orbitrap MS） was operated under positive and negative ion mode to collect the data of total ions current（TIC）. The ion source was a heated electrospray ionization（HESI） source. According to the accurate mass，fragment ions was combined with literature information，compound database and the reference substances were identified to conduct a preliminary identification of the chemical components in E. fortunei. The chromatographic separation was carried out on a Waters HSS T3（250 mm×4.6 mm，5.0 μm） column，using acetonitrile-0.1% phosphoric acid as mobile phase by gradient elution. The collected HPLC data analyzed by a similar evaluation system for chromatographic fingerprint of traditional Chinese medicine（version 2012，National Committee of Pharmacopoeia，China）．HPLC charastersitic chromatograms of 23 batches of E. fortunei were established，facilitating a comparative assessment between the characteristic chromatograms of genuine samples and its respective adulterants，and hierarchical cluster analysis（HCA） was used to verify the common peaks area as the variable. Results showed that a total of 34 chemical components were successfully identified within E. fortunei，including 11 phenylpropanoids，6 pyrrolizidine alkaloids，3 nucleosides，3 amino acids，2 flavonoids，9 other glycoside，acid，alkali，ketone and aldehyde compounds，and the authenticity of 8 components were confirmed through comparison with the reference substance. There are 16 common peaks across the charastersitic chromatograms of 23 batches of E. fortunei and the similarities are greater than 0.85. The similarities between the chromatograms of the adulterants and the reference chromatogram of E. fortunei was 0.452-0.746. According to the area of common peaks，E. fortunei and its adulterants were clearly classified through hierarchical cluster analysis. The established HPLC characteristic chromatograms method of E. fortunei had good specificity，precision，repeatability，stability，and components identification results not only serve as a valuable reference for quality control of E. fortunei but also prove highly effective in the reliable differentiation of E. fortunei and its adulterants，ensuring the quality and efficacy of E.fortunei is of significant importance. At the same time，this research also lays the foundation for further in-depth studies on the chemical composition and pharmacological effects of E. fortunei.关键词：Eupatorium fortunei;characteristic chromatograms;authenticity identification;component analysis;UHPLC-Q-Exactive Orbitrap MS
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发布时间：2024-06-11 - 摘要：In order to investigate the effect of pervaporation on the extraction of volatile components from Yuyan extract，solid-phase supported liquid-liquid extraction/gas chromatography‒mass spectrometry（SLE/GC‒MS） and sensory characteristics quantitative description method were used to analyze the separated sample solution for non-targeted analysis and aroma characteristics evaluation.And stoichiometry was used to explore the difference of sample components，screen the key difference components and analyze their correlation with sensory aroma characteristics. The results showed that：（1） Compared with the original solution，the sample solution obtained by pervaporation separation under the optimized working conditions was significantly improved in the style of fruit aroma，fragrance and sweet aroma，and the paste aroma was weakened，in which the aroma attribute score of the intercepted solution was improved as a whole，and the permeate and cleaning solution were slightly weakened；（2） A total of 101 compounds were detected in different sample solutions，including 13 kinds of substances，such as alcohols，esters，aldehydes，ketones，acids，phenols，hydrocarbons and others mainly composed of alkaloids. Hydrocarbons，ketones and others accounted for a large proportion of volatile components. The membrane components had greater selectivity for hydrocarbons，alcohols and other components，and different solvent systems had greater influence on the concentration of alcohols，ketones，esters and phenols；（3） Principal component analysis showed that the components of sample stock solution and retention solution were relatively consistent，and they were effectively distinguished from permeating solution and cleaning solution. Orthogonal partial least squares discriminant analysis screened 28 different compounds（VIP>1，P<0.05）. Partial least squares regression analysis showed that the characteristic volatile components were positively correlated with the aroma indexes of flue-cured tobacco，such as tobacco aroma，wood aroma，fragrance，sweet aroma and burnt aroma. The results provide guidance for the extraction of Yuyan extract by pervaporation，and then provide technical support for the fine separation and processing of natural plant aroma raw materials.关键词：pervaporation;Yuyan extract;gas chromatography-mass spectrometry;flavor components;sensory characteristics;chemometrics
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发布时间：2024-06-11 - 摘要：Electronic cigarettes（e-cigarettes） are popular nicotine delivery devices. e-cigarette liquid is a complex mixture of ingredients with a viscous base，in addition to the propylene glycol（PG），vegetable glycerin（VG） and flavorings，illicit drugs are often added. Testing for glamorous flavors and illicit drugs in e-cigarettes is a common request from health surveillance，forensic science and market regulation. In this work，we have combined thin-film solid-phase microextraction with a simple gas chromatography-mass spectrometry method. The established method realized the micro-total analysis of low-boiling-point flavors and high-boiling-point illicit drugs in headspace of e-cigarettes. A polystyrene-divinylbenzene particle-loaded membrane was prepared by coating. The sampling conditions of flavors and illicit drugs were optimized，and the optimal extraction condition was 30 min at 180 ℃. All the compositions in the headspace of e-cigarettes showed acceptable accuracy. Thermal desorption experiments of membranes were further explored and the results obtained complemented with solvent extraction desorption. However，considering the real case handling situation，solvent extraction was chosed as desorption method for establishing the e-cigarette analytical methods. At the same time，thermal desorption method enriches the selection space for handling e-cigarette related samples. Compared with conventional direct dilution injection and commercial solid-phase microextraction fibers，this method enhances the analytical sensitivity by expanding the adsorption capacity，improving the universality by removing VG and PG. In addition，it is suitable for high-temperature extraction and has the advantage of low cost. Lastly，the proposed method was applied to three seized e-cigarette which results were consistent with the case intelligence，verifying the accuracy of this method. This work provides an efficient and accurate micro-total analytical protocol for flavors and illicit drugs in headspace of e-cigarette，which is important for health，forensic science and the public environment.关键词：e-cigarette;headspace;illicit drugs;thin-film microextraction（TFME）;gas chromatography-mass spectrometry;micro-total analysis
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发布时间：2024-06-11 - 摘要：In order to solve the problem of formation time of inkjet printed documents in forensic field，the volatile components in four models of two brands black inkjet printed documents were quantitatively and qualitatively analyzed by gas chromatography-mass spectrometry（GC-MS）. The samples printed at one certain time were tracked and tested，at regular intervals the printed samples were punched by a micro punch with a diameter of 0.5 mm and the extract was analyzed by GC-MS. Retention time and qualitative ions combined with NIST mass spectrometry library were used for qualitative analysis and internal standard method to determine the concentration of each substance in the extract. The content of volatile solvent C（ng/mm） in the ink blot per unit length（mm） was calculated and used as a quantitative unit of aging of printed samples. The results showed that four experimental samples contained six volatile solvent components，including 2-pyrrolidone，1，5-pentanediol，2-methyl-1，3-propylene glycol，N-hydroxyethyl-2-pyrrolidone，glycerol and triethylene glycol. These volatile components began to volatilize and transfer at the moment the printing ink was entried in the paper，and tended to stabilize. Finally，the content continued to decrease to a certain value. Based on the analysis data measured over different time period，two types of exponential functions were used to analyze the diachronic change of volatile solvents and a single component and time nonlinear regression models including S-curve，Power and Logarithm model，a multi-component and time multiple linear regression model were established to predict the formation time of printed documents and compare the effect of prediction. By comparing the evaluation indexes of the models，it was concluded that the prediction effect of the multiple linear regression model is better for the ink with more solvent sets.关键词：inkjet printing;document formation time;regression models;gas chromatography-mass spectrometry;volatile substances
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发布时间：2024-06-11 - 摘要：In this study，an enzyme-free electrochemical sensor（NF/Co-FePBA/MWCNTs/GCE）was developed by modifying a glassy carbon electrode（GCE） with Co-Fe bimetallic Prussian blue analog（Co-FePBA） and multi-walled carbon nanotubes（MWCNTs）. The Co-FePBA acting as a hydrogen peroxide-mimicking enzyme，electrocatalytically reduced H2O2，generating a strong current response，for the rapid and sensitive electrochemical detection of H2O2 in milk. Under optimal conditions，the sensor demonstrated a broad linear range（0.01 - 5.0 mmol/L） and a low limit of detection（LOD=0.52 μmol/L，S/N=3） for the current response to H2O2. Furthermore，the sensor exhibited strong anti-interference ability and good repeatability，reproducibility and stability. In milk sample detection，the sensor yielded recoveries ranging from 91.3% to 103% with relative standard deviation（RSD） ≤2.7%（n=3）. This electrochemical method enables a low-cost，simple，rapid and highly sensitive detection of H2O2 in milk.关键词：MWCNTs;Co-Fe bimetallic Prussian blue analogues;electrochemical sensing;H2O2;Milk samples
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发布时间：2024-06-11 - 摘要：A new sampling adsorption tube with MIL-101（Cr） as the filler was constructed，which can be used in thermal desorption-gas chromatography-mass spectrometry for the quantitative detection of 15 typical benzene series and chlorinated volatile organic compounds（VOCs）. 15 VOCs showed good linear relationship in the ranges of 0-100 ng，with the correlation coefficients（r2） above 0.99. The detection limits of 15 VOCs were 0.7-1.9 ng. The average recoveries of MIL-101（Cr） packing tubes were 86.0%-126%，91.7%-133% and 77.6%-135% at the spiked dosage of 5 ng，30 ng and 70 ng VOC target pollutant，respectively. The relative standard deviations（RSDs） were 6.6%-18%，2.9%-20% and 1.3%-20%，respectively. And the RSDs of the test stability and repeatability of MIL-101（Cr） packing tubes were 0.50%-14% and 0.30%-18%，respectively. MIL-101（Cr） packing adsorption tube achieves more efficient adsorption enrichment and thermal desorption of benzene series and chlorinated VOCs based on less mass filler，which helps to reduce the penetration risk of sampled gas. This study expands the practical application scenarios of MOFs materials in the field of environmental monitoring.关键词：metal-organic framework;MIL-101（Cr）;thermal desorption-gas chromatography-mass spectrometry;adsorption tube;volatile organic compounds
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发布时间：2024-06-11 - 摘要：To achieve the rapid and precise identification of cotton and polyester textiles，an analytical method utilizing an electric soldering iron for cauterization combined with soft ionization by chemical reaction in transfer-mass spectrometry（SICRIT-MS） was developed. The SICRIT ion source could ionize gaseous analytes by generating a plasma torch at the inlet of the mass spectrometer through dielectric barrier discharge ionization and maintaining the negative pressure inside the mass spectrometer. The results indicated that the SICRIT-MS method did not necessitate sample pretreatment，was easy to operate，and required only 4-5 s for a single data acquisition. Subsequently，a prediction model based on the random forest algorithm was established using the acquired mass spectrometry（MS） fingerprint data. The random forest model was optimized using the GridSearchCV function from the Scikit-learn library and underwent validation both through five-fold cross-validation and out-of-bag validation，yielding misclassification rates of 2.50% and 2.52%，respectively. According to the out-of-bag validation confusion matrix，the model achieved a prediction accuracy of 97.5%，with precision，recall，and F1 score for cotton and polyester samples all exceeding 95%，thereby meeting the requirements for rapid identification. This method can serve as a technical reference for the authentication and quality evaluation of cotton and polyester textiles.关键词：flow-through dielectric barrier discharge ionization mass spectrometry;random forest model;cotton;polyester;rapid identification
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发布时间：2024-06-11 - 摘要：An ultra-high performance liquid chromatography-Q-Exactive-orbitrap mass spectrometric（UHPLC-QE-Orbitrap MS） method was used to analyse 18 batches of Bovis Calculus（BC） and Bovis Calculus Sativus（BCS） samples. Compound Discoverer software was used to identify the bile acid components，and the chemical statistical analysis was used to screen the differential components from different types of BC samples. The results showed that 30 bile acid components were identified based on the accurate m/z ratio data and the fragment informations from mass spectrometry. Clustering analysis results indicate that the trend of BCS is consistent with its place of production，while the trend of BC is independent of its source. The load plot of principal component analysis shows that cholic acid and deoxycholic acid contribute significantly to the principal component 1，while glycochenodeoxycholic acid，glycodeoxycholic acid，and taurodeoxycholic acid contribute significantly to the principal component 2. By establishing an OPLS-DA model，11 differential bile acid components were selected（VIP>1，P<0.05），and the difference of cholic acid content is the greatest between two groups. Except dehydrocholic acid and glycodehydrocholic acid，the relative content of the remaining 9 differential components in BCS is higher. This research provide a reference for the material basis，quality control，resource development and application of BC and BCS.关键词：UHPLC-QE-Orbitrap MS;Bovis Calculus;Bovis Calculus Sativus;bile acid;differential analysis
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发布时间：2024-06-11 - 摘要：This study presents a way to improve the performance of radio frequency-driven recoupling（RFDR） sequences in solid-state nuclear magnetic resonance（NMR） spectroscopy. Traditional RFDR sequences typically employ single rectangular π pulses，which may prove to be inefficient，especially in experiments under high-speed magic angle spinning（MAS） conditions that have become more popular in recent years. To address this issue，we proposed using composite π pulses to replace the traditional single rectangular π pulses in RFDR sequences. The updated RFDR sequence enables more precise control over nuclei spins and provides better performance in double-quantum（DQ） experiments compared to the traditional module based on single rectangular π pulses. Our focus was specifically on the investigation of multiple composite π pulses，which are suitable for use under high-speed MAS conditions. To evaluate the efficacy of DQ excitation of these composite π pulses within the RFDR sequence，we conducted a comprehensive investigation by using numerical simulations and experiments. Initially，we analyzed the impact of two critical factors on the performance of RFDR in DQ excitation experiments：resonance offset and radio frequency（RF） field inhomogeneity. The resonance offset signifies the difference between the nuclei Larmor frequency and the frequency of the applied RF field，while the RF field inhomogeneity describes the variations in RF field strength throughout the sample. Through a comparative analysis of outcomes from a single rectangular π pulse and multiple composite π pulses，we identified a promising RFDR sequence based on a composite π pulse. Subsequently，this optimized RFDR sequence was integrated into DQ experiments and tested via one-dimensional（1D） and two-dimensional（2D） experiments on 19F for sodium hexafluorosilicate or 1H for L-histidine. The results confirmed that，under high-speed MAS conditions，the RFDR sequence with appropriate composite π pulses can offer several advantages over the traditional RFDR with single rectangular π pulses. Firstly，it achieves higher efficiency in homonuclear DQ excitation，resulting in a significant reduction in experimental time. Secondly，it improves the DQ excitation bandwidth，allowing for improved excitation of nuclei across a broader range of chemical shifts. Lastly，it exhibits good tolerance to RF field inhomogeneity，simplifying experimental setup and facilitating extended experimental durations. In summary，this study explored the efficacy of composite π pulses in optimizing RFDR sequences under high-speed MAS. The utilization of composite π pulse in RFDR sequences enhances robustness and efficiency in DQ correlation experiments，which provides crucial technical support for investigating nuclear interactions within strongly coupled spin systems present in diverse solid-state materials.关键词：solid-state NMR;magic-angle-spinning;composite pulses;dipolar recoupling;double-quantum single-quantum correlation;radio frequency-driven recoupling
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发布时间：2024-06-11
Scientific Papers
- 摘要：This study exploited 3，3'，5，5'-tetramethylbenzidine（TMB） and Rhodamine B as chromogenic probes for α-glucosidase concentration analysis via a colorimetric detection method. On this basis，a smartphone assisted strategy was designed to detect α-glucosidase activity by RGB value analysis of images. The results showed that the absorbance of Fe3+-TMB- Rhodamine B system was linearly related to α-glucosidase concentration in the range of 20-100 U/L，and the detection limit was 3.3 U/L. The RGB values of the sample photos and fluorescence photos were analyzed by photoshop，which showed a linear relationship with α-glucosidase activity in the range of 10-100 U/L，the detection limits were 2.5 U/L and 1.2 U/L for α-glucosidase，respectively. The method has been successfully used to detect α-glucosidase inhibitor acarbose and to quantitatively detect α-glucosidase activity in spiked fetal bovine serum. The smartphone assisted detection method provided a simple，quick and accurate method for clinical analysis of α-glucosidase and rapid screening of enzyme inhibitors.关键词：α-glucosidase;ascorbic acid;smartphone assisted colorimetry;3，3'，5，5'-tetramethylbenzidine（TMB）;Rhodamine B
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发布时间：2024-06-11 - 摘要：Single particle aerosol mass spectrometer（SPAMS） can provide high time resolution and high sensitivity characteristics of particle size distribution and mass spectrometry composition data，and is widely used in the fields of atmospheric aerosol detection and atmospheric scientific research. In the atmospheric environment，sedimentation causes the concentration of large micron-sized particles in the air to be much smaller than that of small sub-micron-sized particles，and there is an order of magnitude difference in the number of particles. In the detection of single particle aerosol mass spectrometry，particles are accelerated through aerodynamics and empowered，which makes small particles fly faster than large particles. This ultimately leads to a significant reduction in the detection probability of single particle mass spectrometry when analyzing large particles such as bioaerosols.Therefore，how to separate large particles from small particles has become the key to improving the effective detection of bioaerosol large particles by SPAMS. This study designed a pumped counterflow virtual impactor（PCVI）. Through 3D modeling，computational fluid dynamics（CFD） simulation，actual experimental testing and detection of algae aerosol，the implementation principle，data simulation，and performance verification and practical application. It is combined with SPAMS to form a PCVI-SPAMS system with cutting capabilities for fine particles. Algae bioaerosol detection has confirmed that the developed PCVI can effectively remove particles with a minimum particle size of less than 2 μm，successfully segment the background of small particles，and achieve expected results.关键词：single particle aerosol mass spectrometer（SPAMS）;pumped counterflow virtual impactor（PCVI）;particle size screening;bioaerosol detection
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发布时间：2024-06-11 - 摘要：In this study，a high performance liquid chromatography method based on immunomagnetic beads purification for the determination of aflatoxin B1（AFB1），aflatoxin B2（AFB2），aflatoxin G1（AFG1） and aflatoxin G2（AFG2）） in vegetable oils was established. First，the aflatoxins in the sample were extracted with methanol-water（70∶30，volume ratio）. The samples were purified with aflatoxin total immunomagnetic bead kit，combined with the immunomagnetic bead automatic workstation，which significantly improved the purification efficiency. Aflatoxins showed good linearity with correlation coefficients（r2） more than 0.99. The limits of quantitation（LOQs） for AFB1 and AFB2，AFG1 and AFG2 were 0.05 µg/kg and 0.10 µg/kg，respectively. The average recoveries of aflatoxins in five commercial vegetable oils ranged from 74.0% to 96.0%，with the intra-day and intra-day relative standard deviations（RSDs） less than 7.0%. The results of the comparison experiments showed that the method had the same performance as the national standard GB 5009.22-2016. The established method has good accuracy and sensitivity，which is suitable for simultaneous quantitative detection of four aflatoxins in vegetable oils.关键词：vegetable oils;aflatoxins;immunomagnetic beads;high performance liquid chromatography
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发布时间：2024-06-11 - 摘要：In this paper，polymerase chain reaction（PCR） was used to amplify nucleic acid，lateral flow immunoassay（LFIA） was used to detect nucleic acid，and a rapid detection method for African swine fever virus nucleic acid was established. In this study，by designing primers，the positive plasmid pUC57-ASFV-（1-1941） was constructed as a quality control product and colloidal gold particles were prepared by trisodium citrate reduction method for antibody labeling to establish an immunoassay method. Under the optimal experimental conditions，the plasmid concentration was in the range of 1.6×10-2-1.6×108 copies/μL，the detection limit of pUC57-ASFV-（1-1941） positive plasmid was 1.6 copies/μL，the method had no cross with other pig viruses and had good specificity.The established method can be used as an auxiliary method for field screening of African swine fever.关键词：African swine fever;polymerase chain reaction（PCR）;immunochromatography;visualization
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发布时间：2024-06-11 - 摘要：Using polylactic acid modified waxy corn starch as raw material，the effects of different amylases on reducing sugar content of polylactic acid modified waxy corn starch were investigated，and the optimal enzymolysis method was obtained：isoamylase hydrolysis for 10 h，pullulanase hydrolysis for 10 h，α-amylase hydrolysis for 10 h，and β-amylase hydrolysis for 12 h. The enzymolysis products were extracted with cyclohexane，the results of 1H NMR showed that carbohydrates containing lactic acid groups could be effectively extracted and enriched，and separated from unsubstituted carbohydrates；Mass spectrometry analysis showed that polylactic acid modified waxy corn starch was mainly composed of lactic acid ester and dipolylactic acid ester. This study explored and established an effective separation and analysis method，and promoted the scientific understanding of the fine structure of starch esters.关键词：polylactic acid modified waxy corn starch;enzymatic hydrolysis;reducing sugar content;cyclohexane extraction;lactate ester
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发布时间：2024-06-11 - 摘要：In this paper，a liquid chromatography-tandem mass spectrometry（LC-MS/MS） method was developed for the determination of scopolamine，atropine，diphenidol，theophylline，diphenhydramine and benzophenone in dried blood spots（DBS）. A dried blood spot was prepared by taking 20 µL of blood，extracted by methanol-acetonitrile（8∶2，volume ratio） as solvent by ultrasonication，separated on a Thermo Gold ODS（150 mm×2.1 mm，5 µm） column，with methanol-5 mmol/L ammonium acetate solution（containing 0.2% glacial acetic acid，pH 4.0） was used as the mobile phase for gradient elution，and then measured in multiple reaction monitoring（MRM） mode of the positive-ion mode，and quantified by external standard method. The results showed that the linearity of the six targets in dried blood spots was good within a certain mass concentration range，and the correlation coefficients（r2） were not less than 0.993 0. The limits of detection（LODs） ranged from 3 to 30 ng/mL，and the limits of quantification（LOQs） ranged from 10 to 100 ng/mL. The average recoveries of the six targets ranged from 88.8% to 108% at low，medium and high concentration levels，with the inter-day and intra-day relative standard deviations were less than 15%. The method was simple and fast，with high accuracy and sensitivity，and has been successfully applied to the detection of one case of difenidol poisoning，which provides a new method for the determination of cases of motion sickness drug poisoning.关键词：dried blood spot;motion sickness drugs;metabolite;liquid chromatography-tandem mass spectrometry
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发布时间：2024-06-11
Experimental Techniques and Methods
- 摘要：At present，nanoenzymes，as a kind of nanomaterials with natural mimic enzyme activity，have been widely used to develop novel biosensors for the detection of fungal toxins because of the combination of nanomaterial properties and good catalytic properties similar to those of natural enzymes. According to the signal transduction system of biosensors，there are three main types of nanoenzyme biosensors，namely，colorimetric，fluorescent and electrochemical methods. The applications of nanoenzyme biosensors in mycotoxin detection in recent years are reviewed，and the advantages of the three types of nanoenzyme biosensors in mycotoxin detection is discussed. Finally，an outlook is given on the current problems and prospects for development.关键词：food analysis;nanoenzyme;biosensors;mycotoxins;food safety
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发布时间：2024-06-11
Review
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