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1.
A fast method was designed for the simultaneous determination of amphetamine (A), methamphetamine (MA), PMA, MDA, MDMA, MDEA and MBDB in urine. The drugs were analysed by LC (ESI)-MS/MS, after a simple liquid-liquid extraction in the presence of the deuterated analogues. Reverse phase separation on an Atlantis dC18 Intelligent Speed column was achieved in less than 4 min under gradient conditions, and the total run time was 8 min. The method was fully validated, including linearity (1-1000 ng/mL for A, MDMA, MDEA and MBDB; 2-1000 ng/mL for MDA and PMA; 1-200 ng/mL for MA; r2>0.99 for all compounds), recovery (>80%), within-day and between-day precision and accuracy (CV and MRE<12.7% for intermediate level and ULOQ, and <17.2% for LLOQ), limit of detection (0.2 ng/mL for MDMA, MDEA and MBDB; 0.5 ng/mL for A, MA and PMA; 1 ng/mL for MDA) and quantitation (1 ng/mL for A, MA, MDMA, MDEA and MBDB; 2 ng/mL for MDA and PMA) and relative ion intensities. No matrix effect was observed. The procedure proved to be sensitive, specific and rapid, and was applied to real forensic cases.  相似文献   

2.
This paper describes the analytical methodology for the determination of MDMA, MDA, MDEA and MBDB in oral fluid. After a liquid–liquid extraction, the analysis was carried out by high performance liquid chromatography (HPLC), with fluorescence detection. The detector wavelength was fixed at 285 nm for excitation and 320 nm for emission. The mobile phase, a mixture of phosphate buffer (pH = 5) and acetonitrile (75:25), and the column, Kromasil 100 C8 5 μm 250 mm × 4.6 mm, allowed good separation of the compounds in an isocratic mode in only 10 min. The method was validated and showed good limits of detection (2 ng/mL) and quantitation (10 ng/mL) for all the amphetamine derivatives. No interfering substances were detected. A stability study of these compounds in oral fluid stored at three different temperatures (−18, 4 and 20 °C) over 10 weeks was conducted, showing a time-dependent degradation of the four compounds.  相似文献   

3.
The in vitro production of GHB was observed in freshly collected, untreated whole blood samples using glass BD-Vacutainers and polypropylene S-monovettes. GHB concentrations were determined daily over a period of one week and after 3, 6 and 9 weeks again. Furthermore, the GHB concentration in 40 untreated random whole blood samples stored at 4°C for a longer period of time (10 samples 12 month, 10 samples 24 month and 20 samples 36 month) was also determined. For comparison, the in vitro production of GHB in freshly collected and prepared serum samples was observed. GHB serum concentrations were determined three times over a period of one week and once again after six weeks. Sample preparation was performed by means of methanolic extraction following the precipitation of whole blood and serum samples. A methanolic standard calibration was done in a low range of 0.005-0.1 μg/mL (LOD: 0.004, LLOQ: 0.013). For quantification a spiked blood bank serum with a determined GHB concentration of 0.09 μg/mL was used. Corrected calibrations in the range of 0.09-5.09 μg/mL were used (LOD: 0.08 μg/mL, LLOQ: 0.30 μg/mL), recovery: 91.3% (high level: 4.09 μg/mL) 50.5% (low level: 0.19 μg/mL). RESULTS: Relevant elevation of GHB was observed in all whole blood samples stored in liquid form (4°C or room temperature). In two of the 40 whole blood samples stored over a longer period of time at 4°C, GHB concentrations in the range of 13 μg/mL were even determined. These findings constitute grounds for caution. Even a GHB cut-off level of 5 μg/mL cannot be considered as "absolutely positive" proof of a case of exogenous administration, at least in untreated liquid blood samples in long time storage. However, no significant elevations of GHB were otherwise observed in any of the serum samples independently of storage temperature nor in the whole blood samples that were frozen for storage. CONCLUSIONS: The results suggest that the cut-off for exogenous GHB of 5 μg/mL could be lowered significantly, with the consequence of winning valuable time for the potential victim, but only if serum is collected for GHB determination or if the whole blood sample is frozen immediately after collection and the procedure well documented.  相似文献   

4.
The prevalence and age distribution of 3,4-methylenedioxymethamphetamine (MDMA) and 3,4-methylenedioxyamphetamine (MDA) in hair samples by gas chromatography/mass spectrometry (GC/MS) were studied. The recoveries obtained from hair were 97% and 99% for MDMA and MDA, respectively. The inter- and intra-assay precision and accuracy were determined. Out of 791 hair samples, 44 (5.6 %) contained MDMA and/or MDA. Out of these 44 subjects, urinalyses from 35 were negative for both MDMA and MDA, while only 9 were positive. We also evaluated concentrations of MDMA and MDA, and the metabolite-to-parent drug ratios. This study showed that the abuse of MDMA or MDA was found principally among young adults and male abusers. We found the epidemiology of ecstasy users in Korea between March 2002 and April 2003.  相似文献   

5.
A rapid, accurate, precise, reproducible, economical, and environmentally gentle method using capillary electrophoresis (CE) is presented for the routine analysis of methamphetamine, amphetamine, MDA, MDMA, MDEA, and cocaine in seized drugs. The methodology uses a 32 cm by 50 microm capillary (length to detector 23.5 cm) with a commercially available buffer kit and diode array UV detection. Dynamic coating of the capillary surface is accomplished by flushing with base for 1 min, a proprietary polycation for 1 min, and then a proprietary polyanion for 2 min. This approach provides a relatively high and stable electroosmotic flow (EOF), even at low pHs. The background electrolyte (BGE) contains 75 mM phosphate buffer (pH 2.5) with the same polyanion as above. Using this methodology, amphetamine, methamphetamine, MDA, MDMA, MDEA, and an internal standard (n-butylamphetamine) are baseline resolved in less than 5 min. The run-to-run migration time %RSDs and peak area %RSDs are typically <0.3% and <2.1%, respectively. The day-to-day and capillary-to-capillary migration time %RSDs are <1.5% and <2.1%, respectively. The %RSDs of the relative migration times compared with the internal standard on a day-to-day and capillary-to-capillary basis are <0.2% and <0.06%, respectively. The linear dynamic range using peak areas range from 0.003 to 0.10 mg/mL. The correlation coefficients are >0.9998, with all calibration curves passing at or near the origin. Similar data are obtained for cocaine and its internal standard henyltoloxamine. None of the compounds usually encountered in illicit samples interfere with the target compound (e.g., methamphetamine and cocaine) or the internal standard. Quantitative results for synthetic mixtures and seized exhibits are in good agreement with actual values, and also with results obtained from other techniques. The relatively high EOF for the dynamically coated capillary system allows for the screening of basic, acidic, and neutral adulterants in drug seizures; identification is facilitated by the use of automated UV library searches.  相似文献   

6.
A newly synthesized designer drug, para-methoxyethylamphetamine (PMEA) was unexpectedly detected in the postmortem specimens of fatality involving drug intoxication in 2005, Japan. For unequivocal identification, the isomeric discrimination of PMEA and its positional-isomers was performed by GC/MS with the trifluoroacetylation. In order to prove the intake of PMEA, the characteristic metabolites of PMEA were also identified by GC/MS analysis of the urine specimen with trifluoroacetylation. As a result, para-methoxyamphetamine, para-hydroxyethylamphetamine (POHEA) and para-hydroxyamphetamine were identified as the major metabolites of PMEA. For the quantitative analyses of PMEA and its three metabolites in body fluids, an automated column-switching LC/MS procedure was developed, and applied to the postmortem blood and urine specimens. In this fatal case, blood concentration of PMEA was estimated to be 12.2 microg/mL and this level seemed extremely high in comparison with lethal blood-levels of its analogues, representing acute-intoxication of the victim. Based on the quantitative results, PMEA was found to be extensively metabolized to POHEA via O-demethylation, partly followed by its conjugation.  相似文献   

7.
The use of amphetamine and 'ecstasy' (MDMA) has increased exponentially in many European countries since the late nineties, leading to a rapid growth in the number of clinical and forensic analyses. Therefore, a rapid screening procedure for these substances in biological specimens has become an important part of routine toxicological analysis in forensic laboratories. The objective of this study was to evaluate the Cozart amphetamine enzyme-linked immunosorbent assay (ELISA) for the screening of plasma samples and oral fluid samples (collected with the Intercept device). Authentic plasma samples from drivers (n=360) were screened, using an 1:5-fold dilution. True positive, true negative, false positive and false negative results were determined relative to the in-house routine GC-MS analysis. Samples consisted of 144 amphetamine-only positives, 141MDMA/MDA-only positives, and 74 negatives when using the limit of quantitation as the cut-off level for confirmation (10 ng/mL). Using these results, receiver operating characteristic (ROC) curves were generated and optimal cut-off values for the screening assay were calculated. Analysis showed that the ELISA is able to predict the presence of either amphetamine or *MDMA/MDA (*MDMA as its metabolite MDA) in plasma samples with 98.3% sensitivity and 100% specificity at a cut-off value of 66.5 ng/mL d-amphetamine equivalents. A similar analysis was conducted on 216 oral fluid specimens collected from a controlled double blind study. Subjects received placebo or a high (100 mg) or low (75 mg) dose of MDMA. Oral fluid samples were collected at 1.5 and 5.5h after administration. Combined results of the analysis of the high and low dose oral fluid samples indicated a screening cut-off of 51 ng/mL d-amphetamine equivalents with both a sensitivity and specificity of 98.6% (using a LC-MS/MS confirmation cut-off of 10 ng/mL). In conclusion, these data indicate that the Cozart AMP EIA plates constitute a fast and accurate screening technique for the identification of amphetamine and MDMA/MDA positive plasma samples and oral fluid specimens (collected with Intercept. It should be emphasized that method validation should be performed for each type of biological matrix.  相似文献   

8.
目的研究固相微萃取(SPME)用于尿中苯丙胺(AMP)、甲基苯丙胺(MET)、3,4-亚甲二氧基苯丙胺(MDA)和3,4-亚甲二氧基甲基苯丙胺(MDMA)的提取。方法样品调节至碱性和用盐饱和后用顶空SPME,内标为MET-d5。萃取纤维为100μm聚二甲基硅氧烷(PDMS)。用气质联用选择离子检测(GC/MS/SIM)。结果0.2μg/ml加标尿样,AMP、MET、MDA和MDMA的富集倍数分别为22,60,13和47。检出限(S/N=3)为0.4~9.5ng/ml。线性范围为0.05~1μg/ml。0.2、0.5和1.0μg/ml加标尿样,相对回收率77.9%~112.4%,变异系数2.7%~18.0%(n=5)。用该方法分析5个案件样品,和常规液液萃取结果接近。结论顶空SPME法用于尿中AMP、MET、MDA和MDMA等化合物的分析,无需有机溶剂,富集效率高,提取-富集-进样一体化,简单方便实用。  相似文献   

9.
A study was performed to acquire urine, serum and oral fluid samples in cases of suspected driving under the influence of drugs of abuse. Oral fluid was collected using a novel sampling/testing device (Dr?ger DrugTest System). The aim of the study was to evaluate oral fluid and urine as a predictor of blood samples positive for drugs and impairment symptoms. Analysis for cannabinoids, amphetamine and its derivatives, opiates and cocaine was performed in urine using the Mahsan Kombi/DOA4-test, in serum using immunoassay and gas chromatography-mass spectrometry (GC-MS) confirmation and in oral fluid by GC-MS. Police and medical officer observations of impairment symptoms were rated and evaluated using a threshold value for the classification of driving inability. Accuracy in correlating drug detection in oral fluid and serum were >90% for all substances and also >90% in urine and serum except for THC (71.0%). Of the cases with oral fluid positive for any drug 97.1% of corresponding serum samples were also positive for at least one drug; of drug-positive urine samples this were only 82.4%. In 119 of 146 cases, impairment symptoms above threshold were observed (81.5%). Of the cases with drugs detected in serum, 19.1% appeared not impaired which were the same with drug-positive oral fluid while more persons with drug-positive urine samples appeared uninfluenced (32.7%). The data demonstrate that oral fluid is superior to urine in correlating with serum analytical data and impairment symptoms of drivers under the influence of drugs of abuse.  相似文献   

10.
Four multi-elementary metal and metalloid quantification methods using inductively coupled plasma mass spectrometry (ICP-MS) were developed and validated in human whole blood, plasma, urine and hair by means of a single preparation procedure for each sample. The ICP-MS measurements were performed using a Thermo Elemental X7CCT series and PlasmaLab software without a dynamic reaction cell. With this procedure 27-32 elements can be simultaneously quantified in biological matrices: Li, Be, B, Al, V, Cr, Mn, Co, Ni, Cu, Zn, Ga, Ge, As, Se, Rb, Sr, Mo, Pd, Ag, Cd, Sn, Sb, Te, Ba, W, Pt, Hg, Tl, Pb, Bi, U. Whole blood, plasma and urine samples (0.4 ml each) were diluted with purified water, acid, triton X100 and butanol. Rhodium was used as internal standard. The urine sample results were corrected for enzymatic creatinine determination. Twenty-five milligrams hair samples were acid mineralized after a decontamination procedure and diluted as previously described for biological fluids. To be validated, each element had to show linearity with a correlation coefficient higher than 0.99. The intra-assay and inter-assay inaccuracy, measured as the variation coefficient, were below 5 and 10% respectively. Global performance was assessed by a quality control program. Our laboratory is a registered participant of the Institut National de Santé Publique du Québec (Sainte-Foy, Canada) inter-laboratory comparison program for whole blood, urine, and beard hair of non-occupationally exposed individuals spiked with selected elements. In our study multi-element metal and metalloid analysis was assessed for 27 elements in whole blood, 27 elements in plasma, 30 elements in urine and 32 elements in hair, from 0 to 25, or 250 to 1000 ng/ml, depending on the element. Quantification limits ranged from 0.002 ng/ml (U) to 8.1 ng/ml (Al) for whole blood, from 0.002 ng/ml (U) to 7.7 ng/ml (Al) for plasma, from 0.001 ng/ml (U) to 2.2 ng/ml (Se) for urine, and from 0.2 pg/mg (Tl) to 0.5 ng/mg (B) for hair. Normal values were determined in whole blood (n=100), plasma (n=100), urine (n=100), and hair (n=45) of healthy volunteers, leading to approximately 10,000 analyses. All results are presented and discussed. Clinical toxicology and forensic toxicology applications are also reported. ICP-MS has made significant advances in the field of clinical biology, particularly in toxicological analysis. This is due to the use of extremely effective equipment that permits better clinical and forensic toxicological analysis of metal and metalloid status of each individual patient.  相似文献   

11.
The Diagnostic Products Corporation Coat-A-Count radioimmunoassay kit for LSD in urine has been evaluated for use in forensic toxicology with a variety of sample types. The cut-offs (defined as the mean response of blank samples plus three standard deviation) for LSD in serum, haemolysed whole blood, urine and stomach contents were 0.06, 0.050-0.055, 0.18 and 0.18 ng/ml, respectively. Preliminary extraction of LSD from the samples is not usually necessary. The precision of the analysis and the recoveries from spiked samples were satisfactory. The cross-reactivities of 2-oxo-LSD, lysergic acid methyl propylamide, lysergic acid monoethylamide and nor-LSD were estimated to be 11,6,2 and 1% respectively relative to LSD (100%).  相似文献   

12.
The ability of five commercially available enzyme-linked immunosorbent assay (ELISA) benzodiazepines to detect clonazepam and 7-aminoclonazepam in blood and urine was investigated. To determine the cross-reactivity of various ELISA assays, drug free blood and urine were fortified with clonazepam and 7-aminoflunitrazepam at concentrations of 1, 2.5, 5, 10, and 25microg/dl. The cross-reactivity, with respect to oxazepam, for clonazepam was 16, 37, 80, 93, and 109% with Immunalysis, Diagnostix, Neogen, OraSure, and Cozart, respectively; for 7-aminoclonazepam, none of the five ELISA assays showed any cross-reactivity above 10%.  相似文献   

13.
GC法检测血液和尿液中甲基苯丙胺和咖啡因   总被引:1,自引:1,他引:0  
目的建立同时测定血、尿中甲基苯丙胺和咖啡因含量的方法。方法应用GC/NPD技术,以4-苯基丁胺为内标,直接碱化,用氯仿提取,三氟乙酸酐衍生化,8CB熔融石英毛细管柱(30m×0.25mm×0.25μm)分析。结果生物样品中甲基苯丙胺与咖啡因在0.012—7.5μg/mL浓度范围内线性关系良好,检测限(S/N=3)依次为1.2ng/mL,0.6ng/mL(血);1.6ng/mL,0.8ng/mL(尿)。苯丙胺在0.017—10.0μg/mL浓度范围内线性关系良好,检测限为1.6mg/mL(血),3.2ng/mL(尿)。所有样本回收率均大于85%。结论本方法准确、灵敏,适用于血、尿中甲基苯丙胺及其代谢物苯丙胺的三氟乙酸酐衍生化物和咖啡因的同时检测,为判定滥用毒品种类、追查毒品来源以及研究生物体内甲基苯丙胺和咖啡因的交互影响提供了检测手段。  相似文献   

14.
It has recently been reported that purity of illicit tablets of ecstasy (MDMA) is now high. Our objective was to confirm whether hair of drug users, who request only ecstasy from their supplier, contains MDMA in the absence of other drugs. GC-MS analysis of scalp hair segments disclosed the presence of MDMA in 19 of 21 subjects and amphetamine/methamphetamine in eight subjects. Surprisingly, seven subjects had hair levels of the MDMA metabolite, MDA, equal to or greater than those of MDMA, suggesting use of MDA in addition to that of MDMA. These amphetamine derivatives might be included by clandestine laboratories to enhance effects of the drug cocktail or because of a perception that MDA synthesis might be simpler than that of MDMA. Drug users and investigators examining possible brain neurotoxic effects of MDMA need to consider that "ecstasy" tablets can contain MDA and methamphetamine despite no demand for the drugs.  相似文献   

15.
多虑平SPE-HPLC分析方法的建立及其应用   总被引:2,自引:0,他引:2  
目的 建立尿样和全血中多虑平的固相萃取 高效液相色谱 (SPE HPLC)分析方法。方法 以多沙普仑为内标 ,1ml尿样或 0 5ml全血用Oasis小柱固相萃取后进Lichrospher 10 0RP 18e ( 2 5 0mm× 4mm ,5 μm)分析柱进行分析 ,2 3 0、 2 5 0nm同时进行检测。结果 尿样和全血中的检测限均 2ng/ml,线性相关系数r≥ 0 9992 ,天内和天间精密度均小于 6 75 % ,绝对回收率大于 85 % ,内源性物质不干扰测定。结论 本法快速、简便、准确 ,可用于实际案例的检测。  相似文献   

16.
A rapid and sensitive method using LC-MS/MS triple stage quadrupole for the determination of traces of amphetamine (AP), methamphetamine (MA), 3,4-methylenedioxyamphetamine (MDA), 3,4-methylenedioxymethamphetamine (MDMA, "ecstasy"), 3,4-methylenedioxyethamphetamine (MDEA), and N-methyl-1-(3,4-methylenedioxyphenyl)-2-butanamine (MBDB) in hair, blood and urine has been developed and validated. Chromatography was carried out on an Uptisphere ODB C(18) 5 microm, 2.1 mm x 150 mm column (Interchim, France) with a gradient of acetonitrile and formate 2 mM pH 3.0 buffer. Urine and blood were extracted with Toxitube A (Varian, France). Segmented scalp hair was treated by incubation 15 min at 80 degrees C in NaOH 1M before liquid-liquid extraction with hexane/ethyl acetate (2/1, v/v). The limits of quantification (LOQ) in blood and urine were at 0.1 ng/mL for all analytes. In hair, LOQ was <5 pg/mg for MA, MDMA, MDEA and MBDB, at 14.7 pg/mg for AP and 15.7 pg/mg for MDA. Calibration curves were linear in the range 0.1-50 ng/mL in blood and urine; in the range 5-500 pg/mg for MA, MDMA, MDEA and MBDB, and 20-500 pg/mg for AP and MDA. Inter-day precisions were <13% for all analytes in all matrices. Accuracy was <20% in blood and urine at 1 and 50 ng/mL and <10% in hair at 20 and 250 pg/mg. This method was applied to the determination of MDMA in a forensic case of single administration of ecstasy to a 16-year-old female without her knowledge during a party. She suffered from hyperactivity, sweating and agitation. A first sample of urine was collected a few hours after (T+12h) and tested positive to amphetamines by immunoassay by a clinical laboratory. Blood and urine were sampled for forensic purposes at day 8 (D+8) and scalp hair at day 60 (D+60). No MDMA was detected in blood, but urine and hair were tested positive, respectively at 0.42 ng/mL and at 22 pg/mg in hair only in the segment corresponding to the period of the offence, while no MDA was detectable. This method allows the detection of MDMA up to 8 days in urine after single intake.  相似文献   

17.
Six groups of common drugs of abuse (cannabinoids, benzoylecgonine, opiates, barbiturates, benzodiazepines and amphetamines) were determined in whole blood after acetone precipitation, using enzyme multiplied immunoassay (EMIT dau) and fluorescence polarisation immunoassay (FPIA--Abbott TDx and ADx) methods. Both methods, designed primarily for urine, allowed the determination of all above mentioned class of drugs but amphetamine. Only 1 ml of a pre- or postmortem blood sample was needed. The sensitivity of cannabinoids determination was higher by FPIA. The FPIA method gave more precise results, particularly in the case of autopsy blood. The method was applied for drug screening in autopsy and police blood samples. The results (both positive and negative) were in agreement with those obtained with chromatographic methods.  相似文献   

18.
The stability of 46 drugs in postmortem femoral blood stored for one year at -20 degrees C was investigated. The drugs included benzodiazepines, antidepressants, analgetics and hypnotics. For seven drugs we found a significant change in the concentration between the first and second analysis. Five substances; ethanol, desmethylmianserin, 7-amino-nitrazepam, THC and zopiclone showed a decrease in the concentration whereas the concentrations of two substances; ketobemidone and thioridazine increased. However, the changes observed were not of such an order that it would affect the interpretation in normal forensic casework. We also investigated the possible influence of potassium fluoride on the concentrations of the 46 drugs in vitreous humor after storage for one year. For two substances, ethanol and zopiclone, there were significantly lower concentrations in the samples without potassium fluoride. Furthermore, we also studied the correlation between the concentrations in femoral blood and vitreous humor. For 23 substances there was a significant difference between the concentrations in the vitreous humor and femoral blood. Significant correlations between the concentrations in these two specimens were found for 23 substances, indicating that vitreous humor can be an alternative specimen when blood samples are not available, provided that such correlation exists for the particular substance. Statistical analysis also revealed a correlation between the degree of protein binding of the different drugs and percentage of vitreous/femoral blood concentrations.  相似文献   

19.
20.
Blood and urine samples are collected when the Norwegian police apprehend a person suspected of driving under the influence of drugs other than alcohol. Impairment is judged from the findings in blood. In our routine samples, urine is analysed if morphine is detected in blood to differentiate between ingestion of heroin, morphine or codeine and also in cases where the amount of blood is too low to perform both screening and quantification analysis. In several cases, the collection of urine might be time consuming and challenging. The aim of this study was to investigate if drugs detected in blood were found in oral fluid and if interpretation of opiate findings in oral fluid is as conclusive as in urine. Blood, urine and oral fluid samples were collected from 100 drivers suspected of drugged driving. Oral fluid and blood were screened using LC-MS/MS methods and urine by immunological methods. Positive findings in blood and urine were confirmed with chromatographic methods. The analytical method for oral fluid included 25 of the most commonly abused drugs in Norway and some metabolites. The analysis showed a good correlation between the findings in urine and oral fluid for amphetamines, cocaine/benzoylecgonine, methadone, opiates, zopiclone and benzodiazepines including the 7-amino-benzodiazepines. Cocaine and the heroin marker 6-monoacetylmorphine (6-MAM) were more frequently detected in oral fluid than in urine. Drug concentrations above the cut-off values were found in both samples of oral fluid and urine in 15 of 22 cases positive for morphine, in 18 of 20 cases positive for codeine and in 19 of 26 cases positive for 6-MAM. The use of cannabis was confirmed by detecting THC in oral fluid and THC-COOH in urine. In 34 of 46 cases the use of cannabis was confirmed both in oral fluid and urine. The use of cannabis was confirmed by a positive finding in only urine in 11 cases and in only oral fluid in one case. All the drug groups detected in blood were also found in oral fluid. Since all relevant drugs detected in blood were possible to find in oral fluid and the interpretation of the opiate findings in oral fluid was more conclusive than in urine, oral fluid might replace urine in driving under the influence cases. The fast and easy sampling is time saving and less intrusive for the drivers.  相似文献   

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