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1.
Solid-phase microextraction (SPME) is a relatively new technique in which a small, polymer-coated fiber is employed to extract volatile and semivolatile organic compounds from the sealed headspace above a questioned sample. SPME, coupled with gas chromatography/mass spectrometry (GC/MS), was used to characterize impurities in illicit methamphetamine samples. Trace impurities present in a specimen were tentatively identified using mass-spectral databases and included 1,2-dimethyl-3-phenyl-aziridine (indicating synthesis via a halogenated ephedrine intermediate), ethyl vanillin (a flavoring compound), and caffeine (a stimulant used as cutting agent). The types and numbers of organic compounds sampled by SPME were compared with those collected by various solvent extraction protocols. In addition to unambiguously confirming the presence of methamphetamine, SPME-GC/MS analyses detected approximately 30 more organic analytes than were found by GC/MS following the ethyl acetate extraction method adopted by the United Nations International Drug Control Programme. SPME-GC/MS is a superior method for generating material "fingerprint" profiles in methamphetamine samples. The detection and characterization of increased points of comparison in drug samples provide more detailed chemical signatures for both intelligence and operational information.  相似文献   

2.
Butane is inhaled in order to achieve a pleasurable state of intoxication. An overdose can lead to death. In two deaths from our own investigation material the circumstances were suspicious for the inhalation of liquid gas, and the presence of butane should be demonstrated in the respiratory gases. For detection, a method of ion trap gas chromatography/mass spectrometry (GC/MS) and tandem-mass spectrometry (GC/MS-MS) was developed, whereby the gas samples from the lung tissue were directly injected into the GC. The GC/MS tests revealed the presence of butane. Moreover, it was found that during the MS-MS tests reaction products appeared which had formed in the ion trap. Systematic investigations of these reaction products showed that these appeared regularly and could be used as additional backup for the proof of butane. Thus phenomena in the ion trap were used which would not have been expected to occur in normal mass spectrometry or tandem-MS and had not been described in the forensic literature so far. The detected amount of butane could be quantified by means of serial dilutions with nitrogen and room air. The described method shows that small molecules or gases can be demonstrated with the ion trap mass spectrometer.  相似文献   

3.
Abstract: This study evaluates the use of polydimethylsiloxane polymer composites (PDMS, Fe–PDMS) as a passive sampling media to preconcentrate analytes found in environmental settings. Samplers were made using commercially available silicone products. The composite samplers were assessed for their sorption properties using Atrazine and Irgarol 1051 as model compounds. The initial study assessed the utility of PDMS sheets as adsorption material by following analyte depletion from spiked water samples by solid‐phase microextraction gas chromatography/mass spectrometry (GC/MS). Follow‐up studies conducted at high and low concentrations using lab manufactured iron‐ PDMS rods (Fe–PDMS) showed effective uptake at differential rates from concentrations ranging between 1 μg/L and 10 μg/L. Adsorption mechanism was reversible, and compounds were recovered from the exposed materials and analyzed by liquid–liquid extraction‐GC/MS. Both composites showed better affinity for Irgarol 1051, 100% removal, than for Atrazine, 30% removal, likely representing their KOW differences, 3.6 and 2.6, respectively. This “proof of concept” study demonstrates the positive implications for the use of silicon polymer composites as a monitoring tool for environmental forensic purposes.  相似文献   

4.
Because of the increasing use of 3,4-methylenedioxymethamphetamine (3,4-MDMA), a rapid and sensitive analytical technique is required for its detection and determination. Using nonaqueous capillary electrophoresis/fluorescence spectroscopy (NACE/FS) detection, it is possible to determine this drug at the level 0.5 ppm without any pre-treatment in less than 5 min. After liquid-liquid extraction, the sample can be condensed and a detection limit of 3,4-MDMA in urine of 50 ppb (S/N = 3) can be achieved. The precision of the method was evaluated by measuring the repeatability and intermediate precision of migration time and the corrected peak height by comparison with a 3,4-MDMA-D5 internal standard. With the conventional GC/MS method, it is necessary to derivatize the 3,4-MDMA before injection and the GC migration time also is in excess of 20 min. Therefore, NACE/FS represents a good complementary method to GC/MS for use in forensic analysis.  相似文献   

5.
During a forensic toxicological GC/MS screening, changed compounds of hydroxyzine were found in a man's urine taken about 20 h after ingesting sake (Japanese liquor) and tranquilizers. The structures of those compounds were assigned to 4-chlorodiphenylmethane(I), p-chlorbenzophenone(III), norchlorcyclizine(IV), 7-(p-chloro-alpha-phenylbenzyl)-2-hydroxy-2H,3H-oxazolo-[3,2 -alpha] piperazine(V), 1-(p-chloro-alpha-phenylbenzyl)-4-methylpiperazine-3-one(VI), N-(p-chloro-alpha-phenylbenzyl)-N'-formylmethyl-N'- hydroxyethyl-1,2-ethenediamine(VII) and 1-(p-chloro-alpha-phenylbenzyl)-4-[2-ethoxy(2-ethoxy)-ethyl] piperazine(VIII) on the basis of the fragmentation patterns and relative retention times except VIII which was identified using the synthesized compound. I, V, VI, VII and VIII have not been reported previously, but the possibility of metabolites of hydroxyzine is still uncertain.  相似文献   

6.
Conventional Gas Chromatography‐Mass Spectrometry (GC‐MS) methods for the analysis of ignitable liquids (ILs) are usually time‐consuming, and the data produced are difficult to interpret. A fast IL screening method using direct analysis in real time mass spectrometry (DART‐MS) is proposed in this study. GC‐MS, QuickStrip DART‐MS, and thermal desorption DART‐MS methods were used to analyze neat ILs and thermal desorption DART‐MS without extraction was used to analyze ILs on five substrates (e.g., carpet, wood, cloth, sand, and paper). Compared to GC‐MS, DART‐MS methods generated different spectral profiles for neat ILs with more peaks in the higher mass range and also provided better detection of less volatile compounds. ILs on substrates were successfully classified (98 ± 1%) using partial least squares discriminant analysis (PLS‐DA) models based on thermal desorption DART‐MS data. This study shows that DART‐MS has great potential for the high‐throughput screening of ILs on substrates.  相似文献   

7.
The usage of herbal incenses containing synthetic cannabinoids has caused an increase in medical incidents and triggered legislations to ban these products throughout the world. Law enforcement agencies are experiencing sample backlogs due to the variety of the products and the addition of new and still‐legal compounds. In our study, proton nuclear magnetic resonance (NMR) spectroscopy was employed to promptly screen the synthetic cannabinoids after their rapid, direct detection on the herbs and in the powders by direct analysis in real time mass spectrometry (DART‐MS). A simple sample preparation protocol was employed on 50 mg of herbal sample matrices for quick NMR detection. Ten synthetic cannabinoids were discovered in fifteen herbal incenses. The combined DART‐MS and NMR methods can be used to quickly screen synthetic cannabinoids in powder and herbal samples, serving as a complementary approach to conventional GC‐MS or LC‐MS methods.  相似文献   

8.
A study was undertaken to assess the stability and the radioimmunoassay (RIA) detection of cocaine, benzoylecgonine (BZE), and 11-nor-delta-9-tetrahydrocannabinol-9-carboxylic acid (THC-COOH) in whole blood while stored in 4 different kinds of blood collection tubes for up to 30 days at refrigeration and room temperatures. At various intervals, the tubes were sampled and analyzed using Abuscreen RIA. Also, semi-quantitative data derived from RIA analysis of forensic blood specimens were compared with quantitative data acquired using gas chromatography (GC) or GC/mass spectrometry (GC/MS) on the same specimens. RIA and chromatographic studies revealed that BZE and THC-COOH were stable in blood under all conditions studied. Cocaine, however, was found not to be stable in blood, especially when stored at room temperatures. Despite cocaine's instability in blood, RIA was able to detect the presence of cocaine and its breakdown products in blood under all conditions studied.  相似文献   

9.
Morphine, the active metabolite of heroin, is rapidly inactivated by glucuronidation at the 3 carbon. Unconjugated (pharmacologically active) morphine was measured in postmortem blood by radioimmunoassay using an antibody-coated tube kit. The kit shows less than 0.2% cross-reactivity with codeine and morphine-glucuronide. Unconjugated morphine concentrations were confirmed by gas chromatography/mass spectrometry (GC/MS) using deuterated morphine as the internal standard. The blood was precipitated with 10% trichloroacetic acid (TCA) and concentrated hydrochloric acid (HCl), centrifuged, and decanted. The supernatant was then either diluted (unhydrolyzed) or heated to 100 degrees C, 30 min (hydrolyzed), followed by a wash with 4:1 chloroform:isopropranol. The upper aqueous layer was then saturated with sodium bicarbonate (NaHCO3) and extracted with 4:1 chloroform:isopropranol. The organic layer was evaporated, derivatized with trifluoroacetic anhydride (TFA), and analyzed by selected ion monitoring (SIM) GC/MS. Comparison of the results for unconjugated morphine by radioimmunoassay and unhydrolyzed morphine by GC/MS gave a correlation coefficient of r = 0.98, n = 100. Unconjugated morphine ranged from 0 to 100% of total morphine with a mean of 42%, n = 200, for heroin or morphine involved deaths. Review of 56 putative rapid deaths gave a mean of 68% unconjugated morphine with a range of 26 to 100%. The ratio of unconjugated to total morphine was found to be stable in postmortem blood after more than a year of storage at room temperature, within the precision of the method.  相似文献   

10.
The cis and trans isomers of 3‐methylfentanyl and its three analogs were chemically synthesized, and these compounds were characterized and differentiated by gas chromatography/mass spectrometry (GC/MS), liquid chromatography/mass spectrometry (LC/MS), and nuclear magnetic resonance (NMR) spectroscopy. The cis and trans isomers of the 3‐methylfentanyl analogs were completely separated by GC/MS. Although the high temperature of the GC injection port caused thermal degradation of β‐hydroxy‐3‐methylfentanyl, the degradation was completely suppressed by trimethylsilyl derivatization. The isomers were also well separated by LC/MS on an octadecylsilyl column with 10 mM ammonium acetate and methanol as the mobile phase. The proton NMR signals were split when the hydrochloride salts of the 3‐methylfentanyl analogs were dissolved in deuterated chloroform because stereoisomers were formed by the coordination of the hydrochloride proton to the nitrogen of the piperidine ring of the 3‐methylfentanyl analogs.  相似文献   

11.
Abstract: Human scent evidence collected from objects at a crime scene is used for scent discrimination with specially trained canines. Storage of the scent evidence is usually required yet no optimized storage protocol has been determined. Storage containers including glass, polyethylene, and aluminized pouches were evaluated to determine the optimal medium for storing human scent evidence of which glass was determined to be the optimal storage matrix. Hand odor samples were collected on three different sorbent materials, sealed in glass vials and subjected to different storage environments including room temperature, ?80°C conditions, dark storage, and UVA/UVB light exposure over a 7‐week period. Volatile organic compounds (VOCs) in the headspace of the samples were extracted and identified using solid‐phase micro‐extraction–gas chromatography/mass spectrometry (SPME–GC/MS). Three‐dimensional covariance mapping showed that glass containers subjected to minimal UVA/UVB light exposure provide the most stable environment for stored human scent samples.  相似文献   

12.
All the commonly used non-steriodal anti-inflammatory drugs (NSAIDs), except mefenamic acid, when extracted from the pharmaceutical dosage forms or the urines of users, and derivatized by silylation and then analysed by GC/MS, gave the mono- or the di-trimethylsilyl derivatives (depending on the number of derivatized groups in the drug) as the sole products. Mefenamic acid gave a mixture of products. When extracted from pharmaceutical dosage froms or from the urines of users, and analysed by GC/MS without derivatization, some of the NSAIDs were separated and detected as the unchanged molecules as the sole products, while others were separated and detected in altered forms as sole products or mixtures, depending on: (a) the solvent in which the extract was dissolved for injection into GC/MS, (b) the chemical structure of the drug, and (c) specifically for diflunisal, the presence or absence of potential methylating and/or acetylating agents on the GC column and/or septum. The main thermally-induced reactions of the underivatized NSAIDs included (i) methyl ester formation at the COOH group when the extract was dissolved in methanol, (ii) decarboxylation (i.e., loss of CO2), (iii) dehydration (i.e., loss of H2O) when the chemical structure permitted, such as for diclofenac, and (iv) cleavage at a carbon-heterocyclic nitrogen bond when one is present in an NSAID. Heating the urine in approximately 2 M HCl at 100 degrees C for 30 min, has been found to be a satisfactory means for effecting hydrolysis of the NSAIDs glucuronide conjugates. No metabolites, resulting from aromatic-ring hydroxylation, have been detected in urine for any of the NSAIDs studied.  相似文献   

13.
Latent fingerprints were successfully visualized using fluorescence lifetime imaging (FLIM) on paper which emits strong fluorescence with a lifetime close to that of fingerprints and thus from which it is difficult for time-resolved spectroscopy to visualize fingerprints. Latent fingerprint samples on paper were excited using a 450 nm or 532 nm nanosecond pulsed-laser, and time-resolved fluorescence images were obtained at a delay time of 6–16 ns in intervals of 1 ns, to the excitation pulse. The excitation beam was expanded using a lens, and the fluorescence from the fingerprints was captured using an intensified CCD camera. Because of the large fluorescence intensity of the background paper of approximately two to four orders of magnitude larger than that of the fingerprint, the fingerprint was not visualized on each fluorescence image by time-resolved spectroscopy. However, the fingerprint was visualized in a FLIM image constructed using a series of the fluorescence images for the case with the fluorescence intensity of the background paper being four orders of magnitude larger than that of the fingerprint. The difference in fluorescence lifetime in the FLIM image of the visualized fingerprint and background paper was in the order of 0.1 ns, which was an order of magnitude smaller than the inherent fluorescence lifetime of a few nanoseconds for the fingerprints and paper. It was demonstrated that, at a background fluorescence intensity with a certain order of magnitude larger than that of fingerprints, FLIM has the potential to visualize latent fingerprints which cannot be visualized by time-resolved spectroscopy.  相似文献   

14.
Two synthetic cannabinoids have been identified, during a survey, as new adulterants; they might have been intended to be used as ingredients for smart drugs. The characterization of these compounds has been made by gas chromatography–mass spectrometry (GC–MS), Orbitrap high resolution mass spectrometry (HRMS) and nuclear magnetic resonance (NMR), leading to the identification of WIN48098, a compound disclosed as a new adulterant in herbal and powder products, and AM679, identified in Italy for the first time.Taking into account the high number of synthetic cannabinoids seized during the last year in Italy, how quickly they appear on the illegal market and the rapidity required for analytical results, a method was developed for the simultaneous quantitation of several synthetic cannabinoids, using gas chromatography–flame ionization detection (GC–FID).  相似文献   

15.
This paper describes the spectroscopic study of the new fingerprint reagent, 1,2-indandione, using nuclear magnetic resonance spectroscopy (NMR) and mass spectrometry (MS). When 1,2-indandione is dissolved in methanol, NMR and MS show formation of a hemiketal similar to that proposed for DFO when it is dissolved in methanol. In contrast to DFO where reactivity with amino acids appears to be enhanced by hemiketal formation with alcohol solvents, the reactivity of 1,2-indandione towards amino acids is diminished by hemiketal formation. Alcohols should be avoided in 1,2-indandione formulations.  相似文献   

16.
This work outlines the unequivocal identification of the "ecstasy" analog, 2-chloro-4,5-methylenedioxymethylamphetamine, using combined gas chromatography/mass spectroscopy (GC/MS) and proton magnetic resonance spectroscopy (1H-NMR). This compound was identified along with 3,4-methylenedioxymethylamphetamine (MDMA) in an illicit tablet seizure, which included 26 off-white tablets.  相似文献   

17.
目的建立羟亚胺及氯胺酮定性和定量分析方法。方法分别使用气相色谱质谱联用法(GC/MS)、液相色谱质谱联用法(LC/MS)和液相色谱紫外法(LC/UV)分析羟亚胺,考察各方法的特点及适用范围。结果采用GC/MS法分析时,进样口的高温会导致部分羟亚胺转化为氯胺酮。LC/MS及LC/UV分析则不存在干扰,羟亚胺和氯胺酮的线性范围分别为3.0~300 ng/mL(LC/MS)、0.02~1.00mg/mL(LC/UV);最低检测限分别为1.0ng/mL(LC/MS)、5.0μg/mL(LC/UV)。结论 GC/MS法仅可确定样品中羟亚胺的存在,不能确认是否含有氯胺酮。LC/MS和LC/UV法可分别用于痕量和常量羟亚胺和氯胺酮定性和定量分析。  相似文献   

18.
A case is presented of a death caused by self-injection of sufentanil and midazolam. Biological fluids and tissues were analyzed for midazolam by high performance liquid chromatography (HPLC) and gas chromatography/mass spectrometry (GC/MS) and for sufentanil by GC/MS. Midazolam was extracted from basified fluids or tissues homogenated with n-butyl chloride and analyzed by HPLC by using a phosphate buffer: acetonitrile (60:40) mobile phase on a mu-Bondapak C18 column at 240 nm. Sufentanil was extracted from basified fluids and tissue homogenates with hexane:ethanol (19:1). GC/MS methodology for both compounds consisted of chromatographic separation on a 15-m by 0.25-mm inside diameter (ID) DB-5 (1.0-micron-thick film) bonded phase fused silica capillary column with helium carrier (29 cm/s) splitless injection at 260 degrees C; column 200 degrees C (0.8 min) 10 degrees C/min to 270 degrees C; and electron ionization and multiple ion detection for midazolam (m/z 310), methaqualone (IS, m/z 235), sufentanil (m/z 289), and fentanyl (IS, m/z 245). Sufentanil concentrations were: blood 1.1 ng/mL, urine 1.3 ng/mL, vitreous humor 1.2 ng/mL, liver 1.75 ng/g, and kidney 5.5 ng/g. Midazolam concentrations were: blood 50 ng/mL, urine 300 ng/mL, liver 930 ng/g, and kidney 290 ng/g. Cause of death was attributed to an acute sufentanil/midazolam intoxication and manner of death a suicide.  相似文献   

19.
The pyrolysis products of smoking methamphetamine mixed with tobacco were determined by gas chromatography (GC) and GC/mass spectrometry (GC/MS) methods. The mainstream smoke contained methamphetamine (14.5% of the initial methamphetamine), phenylacetone (3.1%). N-cyanomethylmethamphetamine (1.9%), trans-beta-methylstyrene (1.7%), N-formylmethamphetamine (1.5%), and other products (each less than 1%). The amount of each pyrolysis product in the sidestream smoke was less than that in the mainstream smoke by a factor of over 5, except for methamphetamine (10.5%) and N-formylmethamphetamine (1.4%). The formation mechanism of these products was investigated, by use of a pyrolyzer, from the standpoint of the material, pyrolysis temperature, and pyrolysis atmosphere. Although several products (for example, dimethylamphetamine and trans-beta-methylstyrene) were formed by thermal self-decomposition of methamphetamine alone, most of the products, except N-cyanomethylmethamphetamine, were formed chiefly by the thermal reaction of methamphetamine with cigarette components. The formation of N-cyanomethylmethamphetamine required air and a high pyrolysis temperature. Air and a high pyrolysis temperature generally accelerated the formation of the pyrolysis products.  相似文献   

20.
目的采用液液提取-GC/MS法检测血液中米氮平。方法用0.1mol/L NaOH溶液调节血液pH值为8~9,以二氯甲烷∶环己烷(4∶6)混合溶剂作为提取溶剂,液液提取法提取血液中米氮平,外标法气相色谱/质谱联用仪定性定量分析。在2mL血中分别添加标准米氮平1、0.5、0.1μg,进行回收率测定。结果血液中添加米氮平的平均回收率为91.5%,方法的工作曲线为Y=1E+06X-16206,相关系数r=0.999 7,线性范围0.5~10μg/mL,最小检出限0.1μg/mL(S/N=46)。结论本文方法操作简便,适合于血液中米氮平的定性、定量分析,可在实际捡案中选择使用。  相似文献   

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