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1.
Over the past three decades, mass spectrometry imaging (MSI) has emerged as a valuable tool for the spatial localization of drugs and metabolites directly from tissue surfaces without the need for labels. MSI offers molecular specificity, making it increasingly popular in the pharmaceutical industry compared to conventional imaging techniques like quantitative whole-body autoradiography (QWBA) and immunohistochemistry, which are unable to distinguish parent drugs from metabolites. Across the industry, there has been a consistent uptake in the utilization of MSI to investigate drug and metabolite distribution patterns, and the integration of MSI with omics technologies in preclinical investigations. To continue the further adoption of MSI in drug discovery and development, we believe there are two key areas that need to be addressed. First, there is a need for accurate quantification of analytes from MSI distribution studies. Second, there is a need for increased interactions with regulatory agencies for guidance on the utility and incorporation of MSI techniques in regulatory filings. Ongoing efforts are being made to address these areas, and it is hoped that MSI will gain broader utilization within the industry, thereby becoming a critical ingredient in driving drug discovery and development.  相似文献   

2.
Mass spectrometry imaging (MSI) is a powerful tool in metabolomics and proteomics for the spatial localization and identification of pharmaceuticals, metabolites, lipids, peptides and proteins in biological tissues. However, sample preparation remains a crucial variable in obtaining the most accurate distributions. Common washing steps used to remove salts, and solvent-based matrix application, allow analyte spreading to occur. Solvent-free matrix applications can reduce this risk, but increase the possibility of ionisation bias due to matrix adhesion to tissue sections. We report here the use of matrix-free MSI using laser desorption ionisation performed on a 12 T Fourier transform ion cyclotron resonance (FTICR) mass spectrometer. We used unprocessed tissue with no post-processing following thaw-mounting on matrix-assisted laser desorption ionisation (MALDI) indium-tin oxide (ITO) target plates. The identification and distribution of a range of phospholipids in mouse brain and kidney sections are presented and compared with previously published MALDI time-of-flight (TOF) MSI distributions.  相似文献   

3.
In Japan, not only the classical stimulant, methamphetamine, but also a wide variety of illicit drugs and designer drugs are abused by juveniles. It is, however, difficult to screen these drugs in human urine due to the poor availability of high-quality standards. Therefore, it is important to develop a screening method that does not require the use of standard compounds. Furthermore, if we can obtain approximate drug concentrations in biological fluids by the first screening procedure, the subsequent treatment of the patient and forensic diagnosis can be carried out more rapidly and exact quantitative analysis performed more efficiently. We have devised a rapid screening method for the simultaneous semi-quantitative analysis of 30 abused drugs using gas chromatography/mass spectrometry (GC/MS) with a retention time locking technique. Based on this method, an 'abused drugs database' was constructed including retention time (RT), qualifier ion/target ion (QT) percentage and calibration curve (values of slope and intercept) using the novel GC/MS software, NAGINATA. We compared the analytical results obtained by this method using the constructed database with those from conventional methods in six forensic cases. The number of confirmed drugs and concentrations obtained by the established method was comparable with that obtained by conventional methods. We found a significant improvement in the time for data analysis, and qualitative and quantitative information about each drug was obtained without using standards. Therefore, this new screening procedure using NAGINATA has potential for the rapid identification of poisoning and should be useful in clinical and forensic toxicological analyses.  相似文献   

4.
Drugs deposited in human teeth are well preserved; the spectrum of toxicological investigations may therefore be supplemented by an analysis method for drugs in teeth. A liquid chromatography–electrospray ionization tandem mass spectrometry assay for the detection and quantification of basic drugs of abuse in bovine dentin samples was developed and validated. The drugs and metabolites amphetamine, methamphetamine, methylenedioxymethylamphetamine, methylenedioxyethylamphetamine, codeine, morphine, cocaine and benzoylecgonine were extracted from 50 mg ground dentin powder by ultrasonication for 60 min in methanol 3 times. The extracts were analyzed on a triple‐quadrupole mass‐spectrometer in multiple reaction monitoring mode. The method was validated and proved to be accurate, precise, selective, specific and stable with good linearity within the calibration range and a lower limit of quantification of 10 to 20 pg/mg. To artificially load bovine dentin samples with drugs, the natural process of de‐ and remineralization in the oral cavity was mimicked by a pH‐cycling experiment. The artificially drug‐loaded dentin samples showed drug concentrations of 20 to 80 pg/mg. The method can be applied in further in vitro experiments as well as in post‐mortem cases, especially where limited sample tissue is available. Copyright © 2014 John Wiley & Sons, Ltd.  相似文献   

5.
In forensic toxicology, hair analysis has become a well established analytical strategy to investigate retrospectively drug abuse histories. In this field, gas chromatography-mass spectrometry and high-performance liquid chromatography-mass spectrometry are currently used, often after preliminary screening with immunoassays. However, on the basis of previous applications to pharmaceutical analysis, capillary zone electrophoresis coupled to ion trap mass spectrometry looks also highly promising. The purpose of the present work was the development of a simple and rapid CZE-MS method for sensitive and quantitative determination of the main drugs of abuse and their metabolites (namely, 6-monoacetylmorphine, morphine, amphetamine, methamphetamine, 3,4-methylenedioxyamphetamine (MDA), 3,4-methylenedioxymethampthetamine (MDMA), benzoylecgonine, ephedrine and cocaine) in human hair. Hair samples (100 mg) were washed, cut and incubated overnight in 0.1 M HCl at 45 degrees C, then neutralized with NaOH and extracted by a liquid-liquid extraction method. CZE separations were carried out in a 100 cm x 75 microm (I.D.) uncoated fused silica capillary. The separation buffer was composed of 25 mM ammonium formate, pH 9.5; the separation voltage was 15 kV. Electrokinetic injections were performed at 7 kV for 30 s under field amplified sample stacking conditions. ESI-ion trap MS detection was performed in the ESI positive ionization mode using the following conditions: capillary voltage 4 kV, nebulizer gas (nitrogen) pressure 3psi, source temperature 150 degrees C and drying gas (nitrogen) flow rate 8l/min. A sheath liquid, composed of isopropanol-water (50:50, v/v) with 0.5% formic acid, was delivered at a flow rate of 4 microl/min. The ion trap MS operated in a selected ion monitoring mode (SIM) of positive molecular ions for each drug/metabolite. Collision induced fragmentation was also possible. Nalorphine was used as internal standard. Under the described conditions, the separation of all compounds, except amphetamine/methamphetamine, MDA/MDMA and morphine/6-MAM was achieved in 20 min, with limits of detection lower than the most severe cut-offs adopted in hair analysis (i.e. 0.1 ng/mg). Linearity was assessed within drug concentration ranges from 0.025 to 5 ng of each analyte/mg of hair. Analytical precision was fairly acceptable with RSD's < or = 3.06% for migration times and < or = 22.47% for areas in real samples, in both intra-day and day-to-day experiments. On these grounds, the described method can be proposed for rapid, selective and accurate toxicological hair analysis for both clinical and forensic purposes.  相似文献   

6.
A new quantitation method for mass spectrometry imaging (MSI) with matrix-assisted laser desorption/ionization (MALDI) has been developed. In this method, drug concentrations were determined by tissue homogenization of five 10 μm tissue sections adjacent to those analyzed by MSI. Drug levels in tissue extracts were measured by liquid chromatography coupled to tandem mass spectrometry (LC/MS/MS). The integrated MSI response was correlated to the LC/MS/MS drug concentrations to determine the amount of drug detected per MSI ion count. The study reported here evaluates olanzapine in liver tissue. Tissue samples containing a range of concentrations were created from liver harvested from rats administered a single dose of olanzapine at 0, 1, 4, 8, 16, 30, or 100 mg/kg. The liver samples were then analyzed by MALDI-MSI and LC/MS/MS. The MALDI-MSI and LC/MS/MS correlation was determined for tissue concentrations of ~300 to 60,000 ng/g and yielded a linear relationship over two orders of magnitude (R(2) = 0.9792). From this correlation, a conversion factor of 6.3 ± 0.23 fg/ion count was used to quantitate MSI responses at the pixel level (100 μm). The details of the method, its importance in pharmaceutical analysis, and the considerations necessary when implementing it are presented.  相似文献   

7.
Liquid extraction surface analysis mass spectrometry (LESA-MS) is a novel surface profiling technique that combines micro-liquid extraction from a solid surface with nano-electrospray mass spectrometry. One potential application is the examination of the distribution of drugs and their metabolites by analyzing ex vivo tissue sections, an area where quantitative whole body autoradiography (QWBA) is traditionally employed. However, QWBA relies on the use of radiolabeled drugs and is limited to total radioactivity measured whereas LESA-MS can provide drug- and metabolite-specific distribution information. Here, we evaluate LESA-MS, examining the distribution and biotransformation of unlabeled terfenadine in mice and compare our findings to QWBA, whole tissue LC/MS/MS and MALDI-MSI. The spatial resolution of LESA-MS can be optimized to ca. 1 mm on tissues such as brain, liver and kidney, also enabling drug profiling within a single organ. LESA-MS can readily identify the biotransformation of terfenadine to its major, active metabolite fexofenadine. Relative quantification can confirm the rapid absorption of terfendine after oral dosage, its extensive first pass metabolism and the distribution of both compounds into systemic tissues such as muscle, spleen and kidney. The elimination appears to be consistent with biliary excretion and only trace levels of fexofenadine could be confirmed in brain. We found LESA-MS to be more informative in terms of drug distribution than a comparable MALDI-MS imaging study, likely due to its favorable overall sensitivity due to the larger surface area sampled. LESA-MS appears to be a useful new profiling tool for examining the distribution of drugs and their metabolites in tissue sections.  相似文献   

8.
This paper describes the application of ultra-performance liquid chromatography/tandem mass spectrometry (UPLC/MS/MS) technology to separate and identify amphetamine-type substances (amphetamine, methamphetamine), common and novel designer analogues (MDA, MDMA, PMA, 4-MTA, MBDB), and ketamine using Acquity UPLC/Micromass Quattro Micro API mass spectrometer instrumentation (Waters Corporation, USA). From injection of drug reference standards, it was demonstrated that these compounds can be identified by product ion mass spectra in less than 4 min total analysis time, indicating that the technological advancements associated with UPLC/MS/MS allow it to serve as a powerful analytical tool for high-throughput testing. In addition to demonstrating the separation and response of these drug compounds under the stated UPLC/MS/MS conditions, we believe the acquired product ion spectra will be a beneficial reference to laboratories interested in incorporating the use of this technology in the routine analysis of drugs of abuse.  相似文献   

9.
Mass spectrometry (MS) imaging is a versatile method to analyze the spatial distribution of analytes in tissue sections. It provides unique features for the analysis of drug compounds in pharmacokinetic studies such as label-free detection and differentiation of compounds and metabolites. We have recently introduced a MS imaging method that combines high mass resolution and high spatial resolution in a single experiment, hence termed HR2 MS imaging. In the present study, we applied this method to analyze the spatial distribution of the anti-cancer drugs imatinib and ifosfamide in individual mouse organs. The whole kidney of an animal dosed with imatinib was measured at 35 μm spatial resolution. Imatinib showed a well-defined distribution in the outer stripe of the outer medulla. This area was analyzed in more detail at 10 μm step size, which constitutes a tenfold increase in effective spatial resolution compared to previous studies of drug compounds. In parallel, ion images of phospholipids and heme were used to characterize the histological features of the tissue section and showed excellent agreement with histological staining of the kidney after MS imaging. Ifosfamide was analyzed in mouse kidney at 20 μm step size and was found to be accumulated in the inner medulla region. The identity of imatinib and ifosfamide was confirmed by on-tissue MS/MS measurements. All measurements including mass spectra from 10 μm pixels featured accurate mass (≤2 ppm root mean square) and mass resolving power of R = 30,000. Selected ion images were generated with a bin size of ∆m/z = 0.01 ensuring highly specific information. The ability of the method to cover larger areas was demonstrated by imaging a compound in the intestinal tract of a rat whole-body tissue section at 200 μm step size. The described method represents a major improvement in terms of spatial resolution and specificity for the analysis of drug compounds in tissue sections.  相似文献   

10.
A pulsed ultrafiltration-mass spectrometric screening method has been developed to evaluate the metabolic stability of drugs. Pooled human liver microsomes containing cytochrome P450 enzymes were trapped by an ultrafiltration membrane in a stirred flow-through chamber, and eight beta-blocker drugs including acebutolol, alprenolol, atenolol, metoprolol, oxprenolol, pindolol, propranolol, and timolol were flow-injected through the chamber along with the cofactor NADPH. The ultrafiltrate was collected, concentrated and analyzed by using liquid chromatography-tandem mass spectrometry (LC-MS-MS) in order to quantitate the unmetabolized fraction of each drug. The metabolic stability of each beta-blocker was determined based on the difference between the corresponding LC-MS-MS peak areas of an experimental incubation and a control without NADPH. A flow-through incubation method, pulsed ultrafiltration metabolic screening minimizes the potential for product feed back inhibition of cytochrome P450 enzymes. The importance of this phenomenon was illustrated by the observation that the metabolic stability of the set of beta-blocker drugs measured using pulsed ultrafiltration more closely resembled the in vivo stability than that determined using a conventional batch incubation with microsomes or an incubation with human hepatocytes. Since a mixture of compounds was analyzed, the relative metabolic stability of each compound could be assessed by comparison to the other compounds in the incubation. This approach might be particularly useful for the ranking of a directed library of drug leads with respect to metabolic stability and then the selection of lead compounds for further drug development.  相似文献   

11.
An air flow-assisted desorption electrospray ionization (AFADESI) MSI device was combined with a highresolution mass spectrometer to optimize the system parameters and achieve more accurate spatial distribution characteristics for compounds of interest while investigating bio-tissue sections. Finally, the parameter conditions that can provide optimal ionic intensity and enhanced resolution were confirmed.  相似文献   

12.
Methodology is presented for identifying an unknown active (pharmaceutical) ingredient (AI) in a counterfeit drug product. A range of mass spectrometric techniques, i.e., accurate mass mass spectrometry, tandem mass spectrometry (MS/MS) and liquid chromatography/mass spectrometry (LC/MS), has been employed to determine the AI in a counterfeit Halfan suspension, an antimalarial drug. In particular, use of LockSpray accurate mass MS/MS allowed identification of parts of the molecule from fragments, hence limiting the number of possible elemental compositions for the nominal mass of 278 found for the AI in the counterfeit product. The analysis of the isotope pattern observed for the protonated molecule further reduced the number of possible elemental compositions. A literature search for readily commercially available compounds of molecular formula C(12)H(14)N(4)O(2)S suggested that the AI was either sulfamethazine or sulfisomidine. An LC/MS separation of those two compounds and reference MS/MS spectra obtained for sulfamethazine and sulfisomidine led to the conclusion that the AI in the counterfeit Halfan suspension is sulfamethazine, which is an antibacterial agent.  相似文献   

13.
Monitoring of amphetamines and designer drugs in human urine is a timely topic in clinical toxicology, surveillance of drug substitution, forensic science, drug testing at the workplace, and doping control. Confirmation testing of urinary amphetamine, methamphetamine, 3,4-methylenedioxymethamphetamine (MDMA, Ecstasy) and 3,4-methylenedioxyamphetamine (MDA) by capillary electrophoresis (CE) combined with atmospheric pressure electrospray ionization and ion trap mass spectrometry (MS) is described. Using an aqueous pH 4.6 buffer composed of ammonium acetate/acetic acid, CE-MS and CE-MS2 provided data that permitted the unambiguous confirmation of these drugs in external quality control urines. Furthermore, other drugs of abuse present in alkaline urinary extracts, including methadone and morphine, could also be monitored. The data presented illustrate that the sensitivity achieved with the benchtop MS is comparable to that observed by CE with UV absorption detection. CE-MS2 is further shown to be capable of identifying comigrating compounds, including the comigration of amphetamine with nicotine.  相似文献   

14.
We have previously developed in‐parallel data acquisition of orbitrap mass spectrometry (MS) and ion trap MS and/or MS/MS scans for matrix‐assisted laser desorption/ionization MS imaging (MSI) to obtain rich chemical information in less data acquisition time. In the present study, we demonstrate a novel application of this multiplex MSI methodology for latent fingerprints. In a single imaging experiment, we could obtain chemical images of various endogenous and exogenous compounds, along with simultaneous MS/MS images of a few selected compounds. This work confirms the usefulness of multiplex MSI to explore chemical markers when the sample specimen is very limited. Copyright © 2013 John Wiley & Sons, Ltd.  相似文献   

15.
16.
Analysis of the major drugs of abuse in meconium has been established in clinical practice for detecting fetal exposure to illicit drugs, particularly for the ready availability of the sample and ease of collection from diapers, compared with neonatal hair and urine. Very little is known about the occurrence and detection possibilities of therapeutic and licit drugs in meconium. Meconium specimens (n = 209) were collected in delivery hospitals, from infants of mothers who were suspected to be drug abusers. A targeted analysis method by liquid chromatography–triple quadrupole mass spectrometry (LC-MS/MS) was developed for abused drugs: amphetamine, methamphetamine, 3,4-methylenedioxyamphetamine, 3,4-methylenedioxymethamphetamine, morphine, codeine, 6-monoacetylmorphine, oxycodone, methadone, tramadol, buprenorphine, and norbuprenorphine. A separate LC-MS/MS method was developed for 11-nor-∆9-tetrahydrocannabinol-9-carboxylic acid. A screening method based on LC coupled to time-of-flight MS was applied to a broad spectrum of drugs. As a result, a total of 77 different compounds were found. The main drug findings in meconium were as follows: local anesthetics 82.5% (n = 172), nicotine or its metabolites 61.5% (n = 129), opioids 48.5% (n = 101), stimulants 21.0% (n = 44), hypnotics and sedatives 19.0% (n = 40), antidepressants 18.0% (n = 38), antipsychotics 5.5% (n = 11), and cannabis 3.0% (n = 5). By revealing drugs and metabolites beyond the ordinary scope, the present procedure helps the pediatrician in cases where maternal denial is strong but the infant seems to suffer from typical drug-withdrawal symptoms. Intrapartum drug administration cannot be differentiated from gestational drug use by meconium analysis, which affects the interpretation of oxycodone, tramadol, fentanyl, pethidine, and ephedrine findings.  相似文献   

17.
A microfluidic chip based nano-HPLC coupled to tandem mass spectrometry (nano-HPLC-Chip-MS/MS) has been developed for simultaneous measurement of abused drugs and metabolites: cocaine, benzoylecgonine, cocaethylene, norcocaine, morphine, codeine, 6-acetylmorphine, phencyclidine, amphetamine, methamphetamine, MDMA, MDA, MDEA, and methadone in the hair of drug abusers. The microfluidic chip was fabricated by laminating polyimide films and it integrated an enrichment column, an analytical column and a nanospray tip. Drugs were extracted from hairs by sonication, and the chromatographic separation was achieved in 15 min. The drug identification and quantification criteria were fulfilled by the triple quardropule tandem mass spectrometry. The linear regression analysis was calibrated by deuterated internal standards with all of the R 2 at least over 0.993. The limit of detection (LOD) and the limit of quantification (LOQ) were from 0.1 to 0.75 and 0.2 to 1.25 pg/mg, respectively. The validation parameters including selectivity, accuracy, precision, stability, and matrix effect were also evaluated here. In conclusion, the developed sample preparation method coupled with the nano-HPLC-Chip-MS/MS method was able to reveal the presence of drugs in hairs from the drug abusers, with the enhanced sensitivity, compared with the conventional HPLC-MS/MS.  相似文献   

18.
A method for the accurate mass measurement of negative radical ions by matrix‐assisted laser desorption/ionisation time‐of‐flight mass spectrometry (MALDI‐TOFMS) is described. This is an extension to our previously described method for the accurate mass measurement of positive radical ions (Griffiths NW, Wyatt MF, Kean SD, Graham AE, Stein BK, Brenton AG. Rapid Commun. Mass Spectrom. 2010; 24: 1629). The porphyrin standard reference materials (SRMs) developed for positive mode measurements cannot be observed in negative ion mode, so fullerene and fluorinated porphyrin compounds were identified as effective SRMs. The method is of immediate practical use for the accurate mass measurement of functionalised fullerenes, for which negative ion MALDI‐TOFMS is the principal mass spectrometry characterisation technique. This was demonstrated by the accurate mass measurement of six functionalised C60 compounds. Copyright © 2010 John Wiley & Sons, Ltd.  相似文献   

19.
陈跃  朱军  于忠山  张云峰  刘耀 《色谱》2012,30(11):1148-1152
建立了超高效液相色谱-串联质谱测定唾液中甲基苯丙胺、吗啡、O6-单乙酰吗啡等3种毒品及其代谢物的方法。以乙腈为提取液沉淀蛋白质法提取,采用基质提取溶液配制标准溶液制作定量曲线。采用BEH HILIC超高效液相色谱柱对待测毒品进行分离;采用电喷雾离子源正离子(ESI+)模式和多反应监测(MRM)模式进行质谱分析,以被测毒品的同位素内标进行定量。结果表明,在10、20、50、100 μg/L 4个添加水平下的回收率范围为(68.7±6.5)%~(110.8±4.6)%,日内精密度小于16.5%,日间精密度小于16.3%; 3种毒品的检出限(LOD,以信噪比(S/N)>3计)和定量限(LOQ,以S/N>10计)分别为0.02~0.05 μg/L和0.1~0.2 μg/L。方法快速、简便、定量准确、灵敏度高;在1 h之内即可对采集的唾液样品进行毒品定性和定量分析,可用于涉嫌吸毒者的快速认定。  相似文献   

20.
Rapid and precise identification of toxic substances is necessary for urgent diagnosis and treatment of poisoning cases and for establishing the cause of death in postmortem examinations. However, identification of compounds in biological samples using gas chromatography and liquid chromatography coupled with mass spectrometry entails time-consuming and labor-intensive sample preparations. In this study, we examined a simple preparation and highly sensitive analysis of drugs in biological samples such as urine, plasma, and organs using thin-layer chromatography coupled with matrix-assisted laser desorption/ionization mass spectrometry (TLC/MALDI/MS). When the urine containing 3,4-methylenedioxymethamphetamine (MDMA) without sample dilution was spotted on a thin-layer chromatography (TLC) plate and was analyzed by TLC/MALDI/MS, the detection limit of the MDMA spot was 0.05 ng/spot. The value was the same as that in aqueous solution spotted on a stainless steel plate. All the 11 psychotropic compounds tested (MDMA, 4-hydroxy-3-methoxymethamphetamine, 3,4-methylenedioxyamphetamine, methamphetamine, p-hydroxymethamphetamine, amphetamine, ketamine, caffeine, chlorpromazine, triazolam, and morphine) on a TLC plate were detected at levels of 0.05 − 5 ng, and the type (layer thickness and fluorescence) of TLC plate did not affect detection sensitivity. In addition, when rat liver homogenate obtained after MDMA administration (10 mg/kg) was spotted on a TLC plate, MDMA and its main metabolites were identified using TLC/MALDI/MS, and the spots on a TLC plate were visualized by MALDI/imaging MS. The total analytical time from spotting of intact biological samples to the output of analytical results was within 30 min. TLC/MALDI/MS enabled rapid, simple, and highly sensitive analysis of drugs from intact biological samples and crude extracts. Accordingly, this method could be applied to rapid drug screening and precise identification of toxic substances in poisoning cases and postmortem examinations.  相似文献   

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