最新刊期
卷 40 ， 期 4 ， 2021
- 摘要：Biosafety,as one of twelve domains of national security,has been attracting close attention from all professions and trades.The“Biosecurity Law of the Peoples Republic of China” enacted in Oct.2020 provides a law basis for coping with biothreats.Both sources of biothreat(deliberate or non deliberate,pathogens,toxins or biological invasions，etc.) and threated subjects(humans,animals,plants and environment) are diverse.At present,coping strategies are still based on the discipline “preventive medicine of anti biothreat”.However,in dealing with the multiple sources of biosafety issues,the limitations of this discipline are witnessed.In this review,the concept evolution of biosafety or biosecurity and the categorization of biothreat are firstly discussed.Meanwhile,a new discipline,ie.science of anti biothreat,is proposed with its scope for laying foundation of disciplinary development in ensuring national security.The tasks of new discipline toward biothreat include:recognition,identification and source tracing,followed by elimination,and finally prevention and control of the biothreat.In order to realize all these objectives,experts from different relevant professions ought to be organized to discuss how to develop this cross disciplinary subject,and how to prepare for handling diverse biothreats,how to educate young people to strengthen their concept and capability of biosafety,how to arrange the scientific and technological research to meet the national biosafety requirement and how to coordinate industrial and academic resources for translating research achievements into national biosafety capabilities,and how to oversight all biosafety related research to make sure no misuse of biological technologies.关键词：biosafety;biothreat;concept;categorization;science of anti biothreat
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发布时间：2023-04-18 - 摘要：Last decade has witnessed the resurgence of occasional terror attacks or extreme events,which poses a serious threat and impediment to public security and ecomonic development.To faciliate the first emergency response,the on site monitoring and detection techniques are urgently needed,and attracting great attention in the field of analytical science.Among various analytical techniques,ambient ionization mass spectrometry(AIMS) once emerged,it is rapidly developing in prosperity due to its powerful ionization capability under atmospheric conditions.Taking advantages of rapid,in situ,real time,high throughput analysis of samples in complex matrixes with simple or no need of sample preparation,AIMS is regarded as a current research hotspot in the analysis of chemical toxicants in the field of public security.According to the ionization and desorption behaviors,AIMS was classified into two categories in this review,containing one step ambient ionization or two step ambient ionization approach.The bibilometric results were then analyzed and presented via VOSviewer software from network visualization of countries,institutions,authors and keywords of recent publications with a total of 2 685 articles.Seven key word clusters were clearly extracted to indicate different technical features and application trends.The representative AIMS techniques were then mainly summarized,as well as their application examples in the detection of illicit drugs,explosives,chemical warfare agents and biotoxins as the main targets.In the present public security field,abundant ambient ionization modes have been adapted to different types of mass analyzers for qualitative and quantitative detection of trace chemical toxicants in complex sample matrices such as body fluid,surface and food.For sensitive screening and detection,researchers devoted to improving ionization efficiency,desorption ability,and integrating simple sample pretreatment.In particular,ambient ionization could be organically combined with miniaturized ion trap mass spectrometry that does not require high vacuum to achieve a rapid and on site detection,of which the promising AIMS techniques include dielectric barrier discharge ionization(DBDI),direct analysis in real time(DART) and paper spray ionization(PSI),etc.Along with the impressive progress of AIMS,a series of technical challenges still need to be effectively addressed,including reproducibility,quantitative ability,analyte scope,sensitivity and complex data analysis capabilities.It is foreseeable that AIMS will realize its great potential in public security field,especially in on site detection under the deep understanding of theory,beneficial to its flexible module design and powerful hybridization or combination potential with other detection techniques.关键词：ambient ionization mass spectrometry;on site detection;public security;chemical toxicants;review
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发布时间：2023-04-18 - 摘要：As a kind of mass destruction weapon,chemcial warfare agents(CAWs) have the characteristics of strong lethality,wide range of influence,difficult protection,easy production and release,which have been used in war conflicts since their birth,and resulting in great threats in modern asymmetric wars and terrorist attacks.Therefore,how to detect chemcial warfare agents in time has become a key research direction for homeland security all over the world.The current mainstream and potential detection techniques for chemical warfare agents are focused in this paper,and the basic principles for various detection techniques and their military and commercial applications are analyzed,as well as the latest research progress.Then,the main related plans of various countries in the world are introduced.Finally,the difficulties and future development of detection techniques for chemcial warfare agents are prospected.关键词：chemcial warfare agents(CWAs);detection techniques;on site detection;review
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发布时间：2023-04-18 -
Research Progress of Surface Enhanced Raman Scattering Method for Detection of Public Safety Poisons
摘要：Common poisons related to public safety may directly threaten peoples life,health and safety in certain ordinary scenarios.Meanwhile,the ultra sensitivity detection characteristic of surface enhanced Raman scattering(SERS) technique could provide very effective analysis strategy and idea for the rapid detection of ultra-trace-level toxicants in complex matrix systems,greatly expanding the practical application scope of this technique,which has a very broad practical application prospect.The progress of a series of basic research results is reviewed in this article,based on SERS technique in the rapid and accurate detection of representative public safety toxic substances,and common toxic target molecules including nodular toxin,mustard gas,and chlorinated amber choline,methyl parathion,cyanide,mercury ion,nitrite and other representative poisons are introduced.From the perspectives of selection and evaluation of different types of SERS substrates,performance evaluation of detection limits,scope of repeatability investigation and practical applications,the SERS spectra of typical target poisons are introduced,as well as the establishment of the surface-enhanced Raman scattering detection system,related parameters and system analysis process.The detection methods for these typical toxicants,and the technical challenges and some possible opportunities they might meet in pratical application are specifically analyzed.Finally,the future development direction for SERS technique to solve the difficult problems of on site actual detection is looked forward to.关键词：surface enhanced Raman scattering;substrate;poisons;detection limit;sensitivity- 6
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发布时间：2023-04-18 - 摘要：As a chemical analysis technology,mass spectrometry has the advantages such as high specificity,high sensitivity and high quantitation accuracy,in comparison with other analysis methods.Mass spectrometry has a great application potential in the area of public security which is featured with needs of rapid on site detection on dangerous chemicals such as drugs,poisons and explosives.The analysis results also need to be quite accurate due to the potential significant impact on public lives following with the corresponding actions.While the specificity and the speed of mass spectrometry in analytical labs could meet the application needs for public security,some substantial development is still required to make the mass spectrometry analysis system suitable for rapid on-site detection.First of all,the instrument itself needs to become portable.Secondly,the sample preparation process needs to be simplified,so that everyone could perform the entire analysis process.Besides,the analysis results should be reported in a fashion directly supporting the decision making.A significant effort has been put into the miniaturization of mass spectrometers,and ambient ionization techniques have also been developed to replace traditional sample preparation.The target analytes in complex sample matrices could be directly analyzed by mass spectrometers without complicated sample treatment or chromatographic separation.In this review, we first introduce the development of ambient ionization techniques and their applications in the field of public security, along with details of several typical ambient ionization techniques(desorption electrospray ionization, direct analysis in real time, laser ablation electrospray ionization, paper spray ionization and paper capillary spray) such as their mechanisms, specifications and applications in public security.On site quantitation methods are also discussed here.Next,the development of integrated miniature mass spectrometry systems is reviewed.Through the two decade development,ambient ionization miniature mass spectrometer has evolved from the initial miniature ion traps to the miniature mass spectrometer that is only compatible with volatile chemicals,then to the miniature mass spectrometer that could analyze non volatile chemicals with traditional atmospheric ionization techniques and finally to the miniature mass spectrometer with ambient ionization source.Then,the applications of ambient ionization miniature mass spectrometer are demonstrated,including on site analysis of drugs of abuse and people with drug addiction,forensic analysis of explosives,agrochemical analysis that is related to food safety,and quality inspection of medicine.Finally,the future of ambient ionization miniature mass spectrometer is also speculated.It is a general trend for miniature mass spectrometer to be used together with ambient ionization.Wider applications of the ambient ionization miniature mass spectrometer could be achieved as it combines with cloud data platform in the future and becomes more intelligent.关键词：ambient ionization;miniature mass spectrometer;public security;application
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发布时间：2023-04-18 - 摘要：Explosives are not only widely used in military wars,but also the first option for terrorists to perpetrate violence because of their high lethality and strong concealment.Based on the urgent need to protect peoples lives and property,different analytical techniques for explosive detection are taken into account in the field of public security worldwide.Compared with other analytical methods,colorimetric detection is one of the most suitable analytical methods for the rapid on site detection of explosives due to its user friendly control,strong anti interference and with no need of advanced analytical equipment.The advances in colorimetric detection of explosives are reviewed in this paper,including summary of research progress in colorimetric probes and colorimetric array as well as their prospect analysis in the field of explosive detection.Especially,a novel artificial olfactory system,ie.colorimetric artificial olfactory system and its application in explosive detection are further emphatically discussed.In addition,the future direction and application prospects of the colorimetric artificial olfactory system in the field of public security are also looked forward to.关键词：explosives;colorimetric detection;probe;sensor array;artificial olfactory system
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发布时间：2023-04-18 - 摘要：Heavy metals are difficult to degrade after polluting the environment and have strong bioaccumulation after entering the organism,which poses a great threat to environmental safety and human health.In addition,some high toxic heavy metal ions could also be used as terrorist agents for deliberate poisoning and threat.Therefore,it is urgent to develop rapid and on site detection methods for heavy metals.Due to the complex pretreatment,high cost and professional needing,the on site applications of traditional instrument detection methods are limited.Recently,with the development of technology and the application of new materials,the sensitivity,portability and cost of fluorescence sensing technology have been greatly improved,among which the aptamer based fluorescence sensing technology has been widely developed and applied in the specific recognition toward heavy metals.In this paper,the applications of aptamer based fluorescence sensors in the detection of heavy metal ions are reviewed in the fields of labeled,unlabeled and nano materials,aiming to provide ideas for the rapid detection of heavy metal ions in the field.关键词：nucleic acid aptamers;fluorescence sensing;detection of heavy metal ions
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发布时间：2023-04-18 - 摘要：γ-Hydroxybutyric acid is an endogenous substance,which has been used in clinical practice since the 1960s,and has attracted extensive attention due to its recreational misuse.In this paper,the metabolism and transformation in vivo,properties and applications of γ-hydroxybutyric acid have been carried on the simple overview.In addition,the recent development of research in pretreatments and analysis methods for determination of GHB in biological samples has been reviewed in details, as well as the latest research progress of cut off values of γ-hydroxybutyric acid in vivo,in order to provide a reference or model for forensic science field to deal with related cases.关键词：γ-hydroxybutyrate(GHB);detection methods;cut-off values research;review
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发布时间：2023-04-18 - 摘要：Rodenticides are the most economical and effective way to control rodents.Meanwhile,most rodenticides have a strong toxicity to human or livestock.The abuse of rodenticides not only poses a risk to non target animals,but also threatens human beings.Numerous human poisoning events occur via accidental exposure,secondary poisoning,suicide attempts and malicious poisonings.As rodenticides poisoning is a serious public health problem,it is urgent and necessary to establish reliable and rapid methods for poisoning diagnosis and rodenticides analysis.Establishing the preclinical detection of rodenticides poisoning,especially the rapid detection methods,are very critical to determine the treatment and rescue measures.The current analyses of rodenticides are mainly dependent on the instrumental methods,including liquid chromatography-mass spectrometry(LC-MS) and gas chromatography(GC).Recently,immunoassay has been used in the rapid detection of rodenticides,due to its simple fabrication and operation,low cost and portability.The advances in poisonings of fluoroacetamide,tetramethylenedisulfotetramine and anticoagulant rodenticides,as well as their detection methods are summarized in this paper,which is anticipated to provide a technical instruction for researchers in the correlative fields.关键词：rodenticides;instrumental analysis;immunoassay;review
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发布时间：2023-04-18 - 摘要：Mushroom poisoning occurs frequently all over the world,which has become one of the most common food poisoning events,as well as the main cause of death from food poisoning.Meanwhile,the most and deadliest toxin in the poisonous mushroom is amatoxin.Hence,rapid and accurate detection of amanitin is of great significance for the identification of toxic source,and the subsequent treatment and prevention of patients.At present,the common methods for amanitin detection include chromatography-mass spectrometry and some other detection techniques based on immune recognition and special chemical structures.It is still the focus of current research that the development of new detection methods with strong specificity,high sensitivity and low time consumption.Therefore,the detection methods of amanitin are reviewed in this paper in order to arouse the attention of research colleagues in this field and stimulate more research ideas.关键词：mushroom poisoning;amatoxin;mass spectrometry;rapid detection;research progress
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发布时间：2023-04-18 - 摘要：Mycotoxins infected foodstuffs may trigger serious health hazards,eg.cancers,deformity and mutation,which has been a global public health concern.Hence,accurate detection data is extremely important to determine the risk posed by mycotoxins to humans.Common detection methods could be used to detect mycotoxins effectively,but it is difficult to conduct any direct analysis if the contents of mycotoxins in complex matrices are rather low,and easy to combine with food matrix components.Consequently,effective sample pretreatment techniques are particularly important to analysis of mycotoxins in actual samples.Solid phase extraction(SPE) is an efficient technique for sample pretreatment,which mainly depends on the extraction materials.In recent years,continual appearances of new SPE materials such as multi walled carbon nanotubes,antibody,molecularly imprinted polymers and metal organic framework materials have contributed to the development and innovation of solid phase extraction technology.These advanced materials either have outstanding selectivity and excellent adsorption capacity toward a single target or could selectively adsorb multiple targets in complex matrix.In addition,the applications of new adsorption materials have greatly improved the recovery rate and detection sensitivity for target substances,shortened the sample pretreatment time,and made the pretreatment process more simple and environmental friendly.Progresses of advanced adsorption materials for mycotoxins sample pretreatment in the past five years are reviewed and summarized in this paper.Furthermore,the advantages,limitations and future trends of these advanced adsorbents are also discussed.Overall,sample pretreatment is promoted theoretically and practically with the development and application of advanced SPE materials.It is hoped that this review may provide a reference for the development of rapid and effective methods for analysis of fungal toxins in food.关键词：mycotoxins;food;solid phase extraction material;sample pretreatment
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发布时间：2023-04-18 - 摘要：The rapid control and prevention of diseases caused by foodborne pathogens is one of the existing food safety supervision issues in both developed and developing countries,which has widely attracted attention from all sections of the community.Up to now,there are some limitations on commonly used methods for detection of foodborne pathogens such as complex steps,time consuming,low sensitivity,poor selectivity,etc.Therefore,development of rapid and reliable methods for detection of foodborne pathogens is still a hot research area for the sake of food safety and public health.As a novel spectroscopic detection technology,surface enhanced Raman spectroscopy(SERS) has shown a broad prospect in the detection of foodborne pathogens with the advantages of high sensitivity,selectivity,rapidness and non destructive detection.In this article,the background and enhanced mechanism of SERS are briefly introduced first,then the SERS active nanostructures used for foodborne pathogen detection are summarized.Furthermore,a comprehensive overview on research progress of direct and indirect SERS methods applied to detection of foodborne pathogens in the past five years is provided,as well as the combination of SERS and other techniques.Meanwhile,the advantages and disadvantages of different SERS substrates and methods are discussed.Finally,the current challenges of SERS technology applied in practical applications are listed in this article,and the possible development trends of SERS in the field of foodborne pathogens detection in the future are put forward.关键词：surface enhanced Raman spectroscopy;foodborne pathogens;label free method;label method
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发布时间：2023-04-18 - 摘要：In the past ten years,chemometric methods and analytical techniques have been combined to characterize and identify samples,resulting in some strong representative sample detection methods with large amount of information.These new technologies and mathematical/statistical methods could be used in the identification and processing of forensic cases to obtain statistical credibility results,thereby contributing to the breakthrough of forensic cases.The methods of multivariate analysis used in the detection of toxic chemicals were discussed in detail,and their advantages and disadvantages were compared and summarized.Meanwhile,the future development and application of chemometrics in chemical attribution of toxic chemicals were prospected.关键词：chemometrics;chemical attribution;toxic chemicals;multivariate analysis method
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发布时间：2023-04-18 - 摘要：Ricin is one of the most deadly toxins known,which could be used as a biological weapon causing potential environmental and food pollution.However,common methods for ricin detection are time consuming and limited due to their complicate and professional laboratory operations.To overcome these limitations of the common detection methods and achieve a simple,rapid and sensitive non laboratory detection of ricin,herein,a novel method was presented for the point of care(POC) detection of ricin B chain(RTB) by using amyloglucosidase loaded nanoliposome(ALN) to amplify the personal glucose meter(PGM) signal.Initially,a hybrid probe was constructed by hybridizing an aptamer on magnetic beads(MBs) with a blocker on ALN,combining the functions of target recognition,magnetic separation and signal amplification together.Then,in the presence of RTB,the blocker linked ALN was released from the surface of MBs after magnetic separation with the formation of RTB aptamer complex.Subsequently,as obtained ALN supernatant was lysed with Triton X-100 to liberate amyloglucosidase to hydrolyze amylose,generating a great number of glucose.Finally,the glucose was quantitatively read out by the PGM in 10 s.Therefore,RTB can be detected by using the enhancement of PGM value.The linear range for the detection was from 0.3 μg/mL to 30 μg/mL and the limit of detection(LOD) was 67 ng/mL.Results showed that the developed method remarkably improved the sensitivity and selectivity for RTB detection,and exhibited a great potential in POC detection of other targets.关键词：point of care testing;nanoliposome;ricin B-chain(RTB);personal glucose meter(PGM)
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发布时间：2023-04-18 - 摘要：Castor bean,crude extract and ricin are potential sources of the “ricin letter” events,which have posed a great threat on public security worldwide.Investigations on tracing the geographic origins of castor beans are of urgent need in case of accidental food ingestion,environmental exposure and deliberate poisoning.Here,based on a thorough optimization of section preparation,matrix application and several key parameters,a novel,sensitive and convenient matrix assisted laser desorption ionization-mass spectrometry imaging(MALDI-MSI) method was firstly established for three endogenous defensive Ricinus communis biomarkers(RCB) with high abundance and low toxicity.Using the mature castor beans obtained from representative geographic origins,Shanxi province in North China and Sichuan province in South China,the abundance and spatial,longitudinal distributions of three RCBs in the castor bean sections were elucidated.Results showed that the RCBs were mainly distributed in the endosperm and embryo of the mature seeds,which exerted distinct abundance difference between Shanxis and Sichuans.Furthermore,the reconstructed 3D MSI model based on the longitudinal visualization in half of a Shanxis seed revealed different abundances of RCBs in main organs of castor beans,consistent with the 2D MSI results.Moreover,the three RCBs all belonged to the component of the highest contribution degree in the non targeted data mining analysis.It is suggested that a whole set of RCBs 1-3 should be integratedly regarded as the traceable biomarkers for different geographical location.The low cytotoxic effect of RCBs assured a safe and reliable alternative way for retrospective analysis.This new MSI strategy exhibits its high sensitivity and favorable applicability in deep insight to unravel the role of defensive peptides biomarkers in intoxication identification,and could timely respond to food and environment sourced hazard emergencies.关键词：castor beans;Ricinus communis biomarkers(RCB);matrix assisted laser desorption ionization-mass spectrometry imaging(MALDI-MSI);retrospective analysis
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发布时间：2023-04-18 - 摘要：Sulfur mustard(SM) is a powerful vesicant chemical warfare agent,which is also a predominant agent found in the abandoned chemical weapons in China by Japanese imperialist army after World War Ⅱ.As a bifunctional alkylating agent,SM reacts rapidly with numerous nucleophiles,eg.water,glutathione,DNA and proteins under physiological conditions via the inter mediate episulfonium ion.Currently,some major metabolites of SM have been used as biomarkers for research and development of toxicity and drug.To address the challenge of early clinical diagnosis and verification of SM exposure,a retrospective method towards exposed urinary biomarkers was developed and applied in this work.A novel ultra performance liquid chromatography-tandem mass spectrometry(UPLC-MS/MS) combined with two steps of solid phase extraction(SPE) was established for simultaneous quantification of seven free metabolites in urine,with limits of detection(LOD) of 5 pg/mL-1 ng/mL and limits of quantitation(LOQ) of 10 pg/mL-5 ng/mL,respectively.The urine matrix interference was reduced effectively due to the established two step SPE procedure(MCX-HLB SPE),leading to the improvement of mass spectrum response to analytes.Especially for thiodiglycol(TDG),a high polarity metabolite,the mass spectrometry response was increased by 64 times after the clean up step with MCX SPE.Therefore,better recoveries of 720%-117% and matrix effects of 853%-117% of the method were achieved.Meanwhile,by the established isotope dilution UPLC-MS/MS for the determination of four urinary SM-nucleobase adducts,an overall analysis of the sulfur mustard urinary biomarkers was performed for a male patient with suspected sulfur mustard exposure with burn degree of Ⅱ° and 1%,who was hospitalized on the 3rd day and discharged on the 7th day after exposure.Three hydrolysis/oxidation products,three glutathione(GSH) adduct β lyase metabolites and four SM-nucleobase adducts were successfully found in the urine samples,including mustard sulfoxide reported as free urinary biomarkers in the first time,which could verify that the patient was indeed suffered from a sulfur mustard exposure.The concentration-time profile demonstrated that the biomarkers reached maximum concentration at 3 to 4 days except for TDG,then decreased and still detectable until the 7th day after exposure.In the 10 detected biomarkers,the hydrolysis products of SM are endogenous substances with background values in vivo as 0-8 ng/mL,meaning that they were not suitable biomarkers for SM exposure in this work.SMO,the direct oxidative metabolite of SM,was identified to be an exogenous substance and could be used as a direct evidence for SM exposure.In addition,similar with SMO,GSH adduct β lyase metabolites are only produced upon exposure to SM.Considering that the concentration of GSH adduct β lyase metabolites was relatively higher than those of hydrolysis/oxidation products and SM-nucleobase adducts,they would be important for early diagnosis and medical treatment monitoring of sulfur mustard exposure.关键词：sulfur mustard;urine sample;ultra performance liquid chromatography-tandem mass spectrometry;biomarker;biomarker profile
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发布时间：2023-04-18 - 摘要：In recent years,new psychoactive substances(NPS) are popular rapidly on the illicit drug market,which have attracted a great concern all over the world.The surge in abuse of NPS has become a serious social problem.As one of the largest growing class of NPS,synthetic cathinones have been widely abused for their cocaine and amphetamine-like pharmacological effects,and have received a widespread attention in many countries.In this article,a gas chromatography-mass spectrometry(GC-MS) with liquid-liquid extraction was developed for the simultaneous determination of eight synthetic cathinones,i.e.methcathinone(MC),4-chloroethcathinone(4 CEC),4 methylpentedrone(4-MPD),3,4-methylenedioxy-N-methylcathinone(MDMC),4′-methyl-α-pyrrolidinopropiophenone(4-MePPP),3,4-methylenedioxy-N-ethylcathinone(MDEC),4′-chloro-α-pyrrolidinopropiophenone(4-Cl-α-PPP) and 3,4-methylenedioxypyrovalerone(MDPV).Firstly,the extraction factors influencing the extraction efficiency were investigated,and the optimal procedures of liquid-liquid extraction were as follows:500 mL blank urine was added with 5 μL internal standard N,N dimethylaniline standard solution(1.00 mg/mL),0.50 mL Na2CO3-NaHCO3 buffer solution(pH 10.80),50 mg sodium chloride and 0.5 mL cyclohexane were vortex-oscillated for 3 min,and then centrifuged at 5 000 r/min for 10 min,the supernatant was injected and analyzed on GC-MS spectrometer.Secondly,the instrumental conditions for GC-MS including GC and MS parameters for simultaneously determining eight synthetic cathinones were optimized in details,and then the qualitative and quantitative analysis of these target compounds in urine were performed by GC-MS,the characteristic ions for qualitative and quantitative analysis were both obtained while the GC-MS spectra were recorded at the same time,then the regression equations,limits of detection(LODs),limits of quantitation(LOQs),inter day and intra day precisions and average recoveries for eight synthetic cathinones in urine were examined,respectively.Experimental results showed that the analytical approach developed was sensitive in qualitative analysis and accurate in quantitative analysis of synthetic cathinones in urine.MC,4 CEC,MDMC and MDEC exhibited good linearity in the concentration range of 0.02-5.00 μg/mL with their LODs and LOQs of 0.01 μg/mL and 0.02 μg/mL,respectively.Their recoveries ranged from 93.2% to 98.5% with the intra day precision and inter day precision not more than 7.8% and 8.8%,respectively.4-MPD,4-MePPP and 4-Cl-α-PPP exhibited good linearity in the concentration range of 0.01-5.00 μg/mL with their LODs and LOQs of 0.005 μg/mL and 0.01 μg/mL,respectively.Their recoveries ranged from 93.6% to 994% with the intra day precision and inter day precision not more than 60% and 7.4%,respectively.MDPV exhibited good linearity in the concentration range of 0.005-5.00 μg/mL with its LODs and LOQs of 0.002 μg/mL and 0.005 μg/mL,respectively,Its recoveries ranged from 92.4% to 97.2% with the intra day precision and inter day precision not more than 4.4% and 53%,respectively.Therefore,the developed method could not only offer a certain scientific and technical support for the relevant material evidence identification and litigation cases,but also provide a tool to combat drug crime in our country.关键词：gas chromatography-mass spectrometry(GC-MS);new psychoactive substances;synthetic cathinones;urine;liquid-liquid extraction
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发布时间：2023-04-18 - 摘要：Ketamine is one of the most frequently abused illicit drug in China while hydroxylimine and o-chlorophenyl cyclopentyl ketone are the main chemical precursors.Most of articles on drug profiling were about tracing the geographical origins or determining synthesizing routine of “worldwide popular drugs” such as heroin,cocaine,methamphetamine and MDMA,by analyzing impurities or by-products of the samples,few articles were about ketamine and its chemical precursors.In this article,ketamine and its chemical precursors profiling were investigated by determine the relevant impurities.Unlike methamphetamine having more than one chemical precursor(ephedrine and phenylactone) and many synthesizing methods(Emde,Ngai,Birch and Reductive amination),all ketamine samples in illicit factory were produced by heating hydroxylimine to reconstruct its molecular structure,and all hydroxylimine samples were synthesized with o-chlorophenyl cyclopentyl ketone which were synthesized by Grignard reagent reaction or Friedel-Crafts reaction.Therefore,it is very important to determine the impurities of samples from the o-chlorophenyl cyclopentyl ketone synthesizing reaction.Gas chromatography-mass spectrometry(GC-MS) was used to detect the impurities in the seized o-chlorophenyl cyclopentyl ketone samples,2-chlorobenzonitile and byproducts of Grignard reagent reactions,including cyclopentanone,cyclopentanol,cyclopentylcyclopentane,2-cyclopentylcyclopentanone and 2-cyclopentylcyclopentanol were signed as the profiling impurities.By synthesizing o chlorophenyl cyclopentyl ketone in lab and detecting it by GC-MS,these 6 profiling impurities were proved to be produced by the reaction of 2-chlorobenzonitile and grignard reagents.Coupling reactions and oxidation reactions of Grignard reagent to produce these profiling impurities were discussed.Hydroxylimine samples were extracted by liquid liquid extraction method,and 4 of those profiling impurities were detected in hydroxylimine samples by GC-MS while the samples were purified in the recrystallization step.Ketamine samples were detected by head space injector GC-MS(HS/GC-MS),and 2 of those profiling impurities were detected while the samples were purified by proceeding recrystallization.Finally,all hydroxylimine and o-chlorophenyl cyclopentyl ketone samples,and 102 of 105 ketamine samples were found to contain 2 of the profiling impurities at least.It could be inferred that Grignard reagent method is the most common routine for the synthesization of o-chlorophenyl cyclopentyl ketone in illicit factory.关键词：ketamine;hydroxylimine;o-chlorophenyl cyclopentyl ketone;profiling impurities;synthesize routine;gas chromatography-mass spectrometry(GC-MS)
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发布时间：2023-04-18 - 摘要：Glyphosate and glufosinate are a class of carcinogenic,non selective and internally suction herbicides,which have received more and more attention from the society.Much work about inspection or identification of glyphosate and glufosinate in the drug related cases are required as poisoning cases of this two herbicides poisoning,suicide and other causes also occur from time to time.To develop a detection method for such herbicides in biological fluids,eg.blood and urine could provide a technical support for the qualitative and detection of cases and provide a reference for clinical toxic analysis and treatment.Therefore,a non derivative high performance liquid chromatography-tandem mass spectrometry was established for the rapid detection of 8 polar pesticides such as glyphosate and glufosinate and their metabolites in biological fluids.8 polar pesticides were separated on a Metrosep A Supp 5 anion column(150 mm×4.0 mm,5 μm),with pure water-200 mmol/L ammonium hydrogen carbonate solution containing 01% ammonia water as mobile phase by gradient elution,and analyzed in negative ion multiple reaction monitoring(MRM) mode.In this study,the chromatographic and mass spectrometry conditions for the instrument were optimized,and the blood and urine of biological fluids were studied.The blood and urine samples were mixed with water and oscillated,then freeze centrifugated with appropriate amount of acetonitrile for 10 min.The supernatant was in turn passed through a Cleanert PEP Plus solid phase extraction column and a 0.22 μm organic micro porous membrane,then collected for analysis.The experimental results showed that there were good linear relationships for 8 polar pesticides in the range of 0.5-50 ng/mL with their correlation coefficients(r2) larger than 0.99.The limits of detection(LOD，S/N≥3) and the limits of quantitation(LOQ，S/N≥10) of this method were in the ranges of 0.08-0.3 ng/mL and 0.3-1 ng/mL,respectively.The matrix effects of the method in blood and urine were in the range of 86.5%-106%，and the recoveries for the target compounds ranged from 81.5% to 114%,with intra day relative standard deviations(intra day RSD,n=6) and inter day RSD of 0.30%-2.8% and 0.50%-5.3%,respectively.With the advantages of simple operation,time saving and labor saving,high sensitivity,good accuracy and good reproducibility,the developed method could be used for the rapid and accurate qualitative and quantitative analysis of 8 polar pesticides,to meet the testing and identification requirements of glyphosate,glufosinate related toxic cases.关键词：polar pesticides;non derivative;biological fluid;high performance liquid chromatography-tandem mass spectrometry
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发布时间：2023-04-18 - 摘要：Benzodiazepines are one of the most frequently prescribed drugs with a broad range of therapeutic effects,including sedative hypnotic,anxiolytic,muscle relexation and anticonvulsant.However,the potential possibility for addiction and abuse in both clinical and forensic cases greatly increased due to the high consumption of benzodiazepines all over the world.For this reason,it is essential to develop a rapid and accurate approach for the determination of benzodiazepines.In this paper,a method was developed for the detection of eight representative benzodiazepines,including diazepam,nitrazepam,clonazepam,flunitrazepam,lorazepam,alprazolam,estazolam,and midazolam in blood samples by high performance liquid chromatography-triple quadrupole linear ion trap mass spectrometry(QTRAP HPLC-MS/MS).Brief steps for the method construction are described as follows.Firstly,the MS/MS library of target analytes with three collision energies were established for the searching and fitting of suspicious detected compounds.Secondly,the instrument conditions were optimized,with Phenomenex Kinetex Biphenyl(100 mm×30 mm,26 μm) as the column for separation,and 5 mmol/L ammonium acetate containing 01% formic acid and methanol as mobile phases for gradient elution.Finally,different pretreatment methods for blood samples,including liquid-liquid extraction using organic solvent,and protein precipitation using methanol or acetonitrile were compared,and the method of acetonitrile protein precipitation was selected owing to the convenience in handling and its relatively high recoveries for target analytes.With the optimized parameter and condition,the blood samples were firstly processed by the acetonitrile protein precipitation method,then centrifuged to obtain the supernatant,and finally filtered for analysis.Scheduled multiple reaction monitoring combined with information dependent acquisition and enhanced product ion(sMRM-IDA-EPI) scanning mode with electrospray ionization(ESI) under the positive condition was applied to data acquisition,with which the suspicious detected compounds could be confirmed by EPI library searching,and quantitative analysis could be carried out with external standard method according to sMRM data.Eight benzodiazepines showed good linear relationships in the concentration range of 05-50 ng/mL with their correlation coefficients(r) larger than 0998.The limits of detection(LOD,S/N≥3) for eight benzodiazepines were in the range of 001-010 ng/mL,while the limits of quantitation(LOQ,S/N≥10) were 010-025 ng/mL.Recoveries for eight compounds at three spiked levels of 10,50 and 20 ng/mL ranged from 793% to 112%,with matrix effects of 798%-972% and relative standard deviations of 43%-11%.Owing to the simple steps of the experiment,the entire process could be completed with reliable and accurate results.The established method was successfully validated by its application in the benzodiazepines screening of a blood sample from the local emergency department.Three compounds of diazepam,alprazolam and midazolam were detected and confirmed,with their concentrations of 3057,651 and 6869 ng/mL,respectively.This method is suitable for rapid diagnosis and condition evaluation of poisoning patients,and provides a technical support for medical emergency and poisoning detection.关键词：high-performance liquid chromatography-triple quadrupole linear ion trap mass spectrometry;blood;benzodiazepines;poisoning detection
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发布时间：2023-04-18 - 摘要：An ultra high performance liquid chromatography-high resolution mass spectrometry(UHPLC-HRMS) was established for the detection of perchlorate in tea based on dispersive micro solid phase extraction(DMSPE).The samples were extracted with acetonitrile,and cleaned up by DMSPE with PSA and PCX as the adsorbents.The chromatographic analysis was performed on a Poroshell 120 PFP column(50 mm×2.1 mm,1.9 μm) with methanol-1.0% acetic acid aqueous solution as the mobile phase by gradient elution,and the internal standard method was used for quantitation.The qualitative screening and quantitative analysis were carried out in negative ion acquisition mode under targeted single ion monitoring(TSIM)/data dependent mass spectrometry(ddMS2) scanning mode.There was a good linear relationship for perchlorate in the concentration range of 0.05-50 μg/L with its correlation coefficient(r2) of 0.999 7,while the limit of detection(LOD) and the limit of quantitation(LOQ) were 0.4 μg/kg and 1.2 μg/kg,respectively.At three spiked levels of 1.2,12 and 120 μg/kg,the average recoveries for perchlorate in tea ranged from 87.4% to 105%,with the intra day relative standard deviations(RSDr) and the inter-day RSD(RSDR) of 0.30%-6.1% and 4.2%-9.2%,respectively.With the characteristics of easy operation,low cost,superior cleanup effect and high sensitivity which could meet the requirements for EU's residue limit,this method is suitable for the detection of perchlorate in tea,and provides a reliable technical means for monitoring and risk assessment of perchlorate in tea in China.关键词：perchlorate;dispersive micro solid phase extraction;high resolution mass spectrometry;tea;matrix effect
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发布时间：2023-04-18 - 摘要：It is well known that direct ionization mass spectrometry(MS) has the advantages of few pretreatments,rapidness,and convenience,which is widely used in the fields of rapid detection of various substances,such as explosives,drugs,food additives,etc.However,for the direct ionization mass spectrometry,there exist large fluctuations in the signal intensities which usually obey the lognormal distributions.As a result,how to identify these signals and classify the samples becomes a real challenge.The common analysis methods for mass spectrum data include the extracted ion current(EIC) and Gaussian mixture model(GMM).Both of these analysis methods make only use of the peak intensity information,but ignoring the peak shape features such as peak position,full width at half maximum(FWHM) and correlation information among multi peaks.In addition,the detection accuracies of these methods also depend on the preset thresholds,which is usually a tedious work to optimize.However,machine learning unlike EIC and GMM could take advantage of all the characteristics of mass spectrum signals to improve the detection performance without a preset threshold.In this work,acetylsalicylic acid(115 samples) was adopted as an analog for explosives in the mass spectrometry detection.In order to improve the detection accuracy especially for dielectric barrier discharge ionization(DBDI) source and mass spectrometer in detection of the samples with low concentrations,the data preprocessing and classification algorithms based on EIC,GMM and machine learning of the direct ionization mass spectrometry were studied.Moreover,2,4,6-trinitrotoluene and ammonium nitrate(110,90 samples,respectively) with a concentration of 1 ng/mL,and blank samples(366 samples) under the same detecting conditions were investigated and analyzed.Results showed that the signal intensities of either the blank samples or the explosive samples with the same concentration,all obey the lognormal distributions,spanning several orders of magnitude.As set forth,the detection results based on the EIC and GMM were found all sensitive to the preset thresholds.However,the random forest(RF) algorithm could be used to improve the classification accuracy,compared with EIC and GMM methods.And the F_score numbers for EIC,GMM and RF are 0.74,0.89 and 0.96,respectively.In addition,with the same analysis methods,MS/MS could significantly reduce the background interference and improve the detection accuracy,compared with the full scan mass spectrometry.In practice,it usually takes 3-6 seconds to acquire the mass spectrum data for each sample.In this work,the analysis time for each single sample data is much less than 0.1 second,which means the algorithm could be adopted to a real time detection.In conclusion,direct ionization mass spectrometry combined with machine learning could meet the needs for rapid,real time and accurate detection of explosives,which exhibits good application prospects.关键词：direct ionization mass spectrometry;explosives;machine learning;rapid detection;lognormal distributions
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发布时间：2023-04-18 - 摘要：In this paper,an on site rapid quantitative analysis device of volatile organic compounds(VOCs) in sealed cabin was developed.The device was based on the metrological sampling-enrichment technique with thin shell metal cylinder type capillary column heater,and micro thermal conductivity detector/micro flame ionization detector.To adapt pressure change in sealed cabin,a fix-volume vacuum tank with a pressure sensor and a temperature sensor was used to calculate the effective sampling volume and the enrichment factor.The enrichment factor was 400 for toluene at an effective sampling volume of 100 mL(converted to standard atmospheric pressure).The column assembly was constructed by wrapping the heating wire and column on the inside and outside layers of a thin shell metal cylinder,respectively.The temperature uniformity of capillary column was less than 0.4 ℃,and a temperature programming rate of 40 ℃/min was obtained.In the heating process from 40 ℃ to 300 ℃ at 10 ℃/min,the power consumption was less than 35 W,while at an isothermal temperature of 300 ℃,the power consumption was only 28 W.The separation performances,including peak width at half height,column efficiency,resolution and repeatability of the column assembly were evaluated and compared with a laboratory chromatograph,proving that the separation performances of the two heating methods were similar.The sampling-enrichment performance was evaluated with varieties of VOCs samples.In the high speed separation mode,53 VOCs could be separated within 5 minutes using a peak width at half height less than 0.8 s for all analytes.The developed device was applied to the rapid determination of hydrocarbons,benzene homogeneous,alcohols,aldehydes,ketones and other VOCs.The performance parameters of the device were satisfactory,compared with those of commercial portable gas chromatography(GC) or gas chromatography-mass spectrometry(GC-MS).
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发布时间：2023-04-18 - 摘要：As one of highly toxic and volatile chemicals,mustard gas has been widely used as a kind of chemical weapon in local wars and terrorist attacks.Realizing the rapid and accurate qualitative identification of mustard gas is the first step to prevent casualties from wars and terrorist attacks.The lab facilities based standard methods accompanied with tedious and time consuming operation are hardly satisfied the demand of emergence.Therefore,it is of great military significance to develop and establish a highly sensitive,accurate,simple and rapid detection technique towards on site detection of mustard gas.Taking the near single molecule level sensitivity and fingerprint resolution of surface enhanced Raman spectroscopy(SERS) herein,the feasibility of SERS for on site and quick detection of trace mustard gas was systematically explored,with 2-chloroethyl ethyl sulfide(2-CEES) as simulant and 50 nm gold nanoparticles colloid as SERS substrate,respectively.It was figured out that：(1) The SERS spectrum of trace 2 CEES showed obvious difference compared with the normal Raman spectrum of 2-CEES,as a result of the hydrolysis of 2-CEES and the accompanied formation of sulfonium;(2) Accordingly,the two characteristic Raman peaks located at 610 and 1 050 cm-1 of sulfonium could be used for the qualitative analysis of trace 2-CEES by SERS.Meanwhile,the lowest detectable concentration of 2-CEES was 10 μg/L.Furthermore,the reproducibility and stability were confirmed on both lab based bench top Raman instrument and portable one.The observation demonstrates that the SERS based strategy is very promising for the on site and rapid qualitative analysis of trace mustard gas in environmental waters.关键词：mustard gas;2-chloroethyl ethyl sulfide(2 CEES);surface enhanced Raman spectroscopy(SERS);gold nanoparticles
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发布时间：2023-04-18 - 摘要：Traditional Chinese medicines(TCMs) play a significant role due to their less adverse reactions and unique medical efficiency,which have attracted more and more attention both at home and abroad.However,TCMs are prone to mildew and generate aflatoxins in production,collection,processing,transportation and storage.Aflatoxins with strong toxicity could not only affect the quality and efficacy of traditional Chinese medicines,but also cause great damage to the liver and other organs of human.A rapid dynamic surface enhanced Raman spectroscopic(D-SERS) method was established for the detection of aflatoxin G1(AFG1) in coix seed,a kind of traditional Chinese medicine.The aflatoxin G1 on the surface of coix seed was extracted by wiping method,while not all of the ingredients in coix seed could be extracted.Therefore,there was less interference of coix seed in SERS spectrum.Aflatoxin G1 was analyzed by D-SERS with gold nanoparticles as the enhanced substrate,which are characterized by their good stability.The detection conditions were optimized.The calibration curves were linear in the range of 8-320 μg/kg,with a linear formula as y=0.029 3x+1.730 7,and a correlation coefficient(r2) of 0.988 4.The limit of detection(LOD) was 5.5 μg/kg,and the relative standard deviation(RSD) was 11%.Results showed that the established method was simple,rapid and cost saving,and it could meet the requirements for rapid detection of aflatoxin G1 in coix seed with good linearity,sensitivity and reproducibility.Therefore,this method has a good application potential in real time and rapid analysis of aflatoxin G1 in Chinese herbal medicines.关键词：wiping method;aflatoxin G1;coix seed;dynamic surface enhanced Raman spectroscopy
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发布时间：2023-04-18
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