GC／MS分析鱼塘水中的五氯酚

目的介绍GC/MS分析鱼塘水中五氯酚的方法。方法将约500ml鱼塘水调至pH=3,用约50ml苯萃取、无水硫酸钠干燥过滤、浓缩至约0.2ml,然后再利用GC/MS联用仪分析。结果用该方法检验出四氯苯酚和五氯苯酚。结论这种方法可用来对鱼塘投毒案件中的水样进行五氯酚的检验。     

五氯酚钠外敷中毒死亡一例报告

五氯酚钠中毒死亡,在法医学检验中比较少见,尤其是外敷中毒死亡更为罕见.现将我院检验五氯酚钠外敷中毒死亡的病例报告如下. 一、病历摘要: 钱某,男32岁,农民,一九八九年七月四日下午八时,吃完晚饭,洗完澡.觉得自己左下肢奇氧(牛皮癣),便向邻居要了五氯酚钠粉末约100g(邻居用于灭蚂蟥),拿回后将二分之一的五氯酚     

微流体分流器用于鱼塘水中灭扫利和五氯酚GC／MS分析

灭扫利通用名为甲氰菊酯，英文名Fenpropathrin，分子量349．43，分子式C22H23NO3。属于拟除虫菊酯类农药。五氯酚钠盐为无色针状结晶物，水溶液呈碱性，是灭生性触杀型除草剂，对人和家畜有一定毒性，但对鱼虾毒性更大，水中含0．1～0．2mg／L即可导致鱼虾死亡。灭扫利和五氯酚在市面上容易得到，致使鱼塘中投毒的案件时有发生。检案中常采用GC／MS技术进行检验，本文在检验中使用一种三路微流体分流器，可使方法更加简便。     

鱼塘水中五氯酚钠的提取及检验探讨

鱼中毒后从鱼塘水中检测毒剂成分比较困难,据调查佛山地区的鱼中毒案件,绝大部分都是五氯酚钠(对鱼毒性极大)所致.为此,笔者专门对此进行了探讨,并连续检测出几宗鱼中毒案件,介绍如下.1 材料和方法1.1 五氯酚乙醇标准液的配制:取五氯酚钠原粉适量加水50ml,搅拌至完全溶解(若有沉淀即过滤,去除滤渣),滴加盐酸直到不再析出自色沉淀,过滤,去除滤液,滤渣反复用蒸馏水洗涤至中性,真空干燥.取干燥粉末0.1g加至10ml容量瓶中,加无水乙醇到刻度.1.2检材提取:提取鱼塘水中的检材,应在死鱼最多的部位提取,或者水不流动的部位提取,并检查鱼塘中及其周围是否有可疑包装物.取检材500ml,放人1000ml梨形分液漏斗中,加盐酸调至酸性(pH=1),剧烈振荡后,加乙醚100ml,充分振摇萃取,静置分层后,将水层转入另一个盛有100ml乙醚的梨形分液漏斗     

用五氟苄基溴对五氯酚进行衍生化的方法

目的五氟苄基溴(PFBBr)衍生化试剂对五氯酚进行衍生化研究。方法运用GC/MS、GC/ECD印证分析衍生化产物。结果改变了五氯酚的挥发性,提高检测灵敏度,在本文控制的实验条件下,五氯酚-PFBBr衍生物的检测限可达1pg。结论为检测微量五氯酚提供了一种有效手段。     

1300Ⅱ型树脂富集提取水中痕量五氯酚钠的研究

<正> 五氯酚钠是含氯酚类农药,对鱼、人和其他动物有毒,常发生水中污染和投毒等案件。长期以来对水中微量五氯酚钠和其他有毒成份的提取常采用有机溶剂萃取的方法,但因其操作繁琐、费时、浪费溶剂和提取率低等因素,有人曾用活性炭富集提取有机毒物,效果较理想。树脂作为富集分离的重要手段已为人们所熟悉,     

尿中五氯酚和2.4-二氯-6-硝基苯酚气相色谱分析

目的建立利用气相色谱分析检测尿中五氯酚和2,4-二氯-6-硝基苯酚的方法。方法取空白尿液添加五氯酚和2.4-二氯-6-硝基苯酚标准品及内标2.4-二氯苯酚,经乙酸酐衍生化后,采用气相色谱法进行检测,并对提取方法、衍生化条件等进行考察。结果经气相色谱分析,尿中五氯酚和2.4-二氯-6-硝基苯酚可得到有效分离,无杂质干扰且峰形较好。在pH值为2条件下,以环己烷作为萃取溶剂为最佳萃取条件。衍生化优选条件为使用10灿乙酸酐并加入10μL无水吡啶,60℃反应30min。结论采用气相色谱法检测尿中五氯酚和2.4-二氯-6-硝基苯酚,方法简单、结果准确,可在实际办案中应用。     

GC/MS和GC法定性定量分析可卡因

目的建立用于可卡因案件检验鉴定的GC和GC/MS定性、定量分析方法。方法通过选择和优化,建立GC、GC/MS法检验可卡因的最佳分析条件;用分别含0.6mg/ml地西泮为内标的0.10、0.20、0.40、0.60、0.80、1.00、1.20mg/ml可卡因标准品乙醇液,考察线性范围和方法检测限。结果分析方法线性方程:GC/FID,Y=1.055X-0.0021,R2=0.9999,GC/NPD,Y=0.556X-0.0016,R2=0.9996;可卡因检测限:GC/FID法10ng,GC/NPD法2ng;分别以所建GC/FID、GC/NPD分析方法和内标法对案件中缴获的可卡因毒品进行定量分析,结果为72%±2.3%,且两方法定量重现性良好。结论本文所建方法可以用于可卡因涉毒案件的检验鉴定。     

固液萃取——导数紫外光谱法测定血中氯敌鼠

氯敌鼠是国内近几年使用的杀鼠剂之一,化学结构属茚满二酮类。在司法鉴定实践中,时有因误吸。投毒氯敌鼠引起的中毒案件发生,而国内对氯敌鼠中毒检验的研究甚少。本文运用固液提取技术和导数紫外光谱技术,对生物检材中氯敌鼠的测定进行了实验研究。结果表明:方法简便、快速、可靠。     

鱼塘水中六氯苯水解产物的检测

<正> 六氯苯(hexachlorobenzene,HCB),也称多氯苯,是一种常见的除草剂。鱼类对六氯苯的毒性比较敏感,常见于鱼塘水中毒鱼案中。本文作者采用固相萃取技术(SPE),分离富集鱼塘水中六氯苯的代谢产物——五氯苯酚,选用GC/MS技术进行分析,检出鱼塘水中的五氯苯酚。使用SPE技术分析检材中的五氯苯酚,具有快速、方便、省溶剂等优点,是一种具有潜力的实用的检验方法。     

The appropriate use of subpopulation corrections for differences in endogamous communities

The bioluminescence response of two genetically modified (lux-marked) bacteria to potentially toxic compounds (PTCs) in stomach contents was monitored using an in vitro assay. Cells of Escherichia coli HB101 and Salmonella typhimurium both carrying the lux light producing gene on a plasmid (pUDC607) were added to stomach contents containing various concentrations of organic and inorganic compounds. There was some variability in the response of the two biosensors, but both were sensitive to the herbicides glyphosate, 2,4-dichlorophenoxyacetic acid (2,4-D), 2,4,5-trichlorophenoxyacetic acid (2,4,5-T); pentachlorophenol (PCP), and inorganic poisons arsenic and mercury at a concentration range likely to be found in stomach contents samples submitted for toxicological analysis. This study demonstrates that biosensor bioassays could be a useful preliminary screening tool in forensic toxicology and that such a toxicological screening should include more than one test organism to maximise the number of PTC's detected. The probability of false positive results from samples containing compounds that may interfere with the assay such as over-the-counter (OTC) drugs and caffeine in tea and coffee was also investigated. Of the substances tested only coffee has the potential to cause false positive results.     

Comparison of results for quantitative determination of morphine by radioimmunoassay, enzyme immunoassay, and spectrofluorometry.

The quantitative results (accuracy and precision) for determination of opiates by radioimmunoassay (RIA), enzyme immunoassay (EMIT), and spectrofluorometry on split samples are compared. A variety of physiological samples were studied, including random urine from a methadone maintenance clinic and postmortem urine, blood, bile, brain, and lung tissue from heroin-induced or heroin-related deaths. The opiate concentrations detected by the two immunoassay methods were in good agreement with each other in the absence of interfering substances which are believed to react with the antimorphine antibodies. The immunoassay results were in agreement within the relative standard deviation with the fluorometry results in 55% of the urine samples and 80% of the blood samples. The immunological methods are superior to fluorometry for quantitation of morphine in urine samples due to quenching interferences in fluorometry from urine. They were comparable to fluorometry for quantitation of morphine in blood samples.     

Research status and prospects of DNA test on difficult specimens

This paper reviews the advances of DNA detection on three types of difficult biological specimens including degraded samples, trace evidences and mixed samples. The source of different samples, processing methods and announcements were analyzed. New methods such as mitochondrial test system, changing the original experimental conditions, low-volume PCR amplification and new technologies such as whole genome amplification techniques, laser capture micro-dissection, and mini-STR technology in recent years are introduced.     

Rapid determination of carboxyhemoglobin in blood by Oximeter

Different methods to determine carboxyhemoglobin (COHb) in blood are described in the literature. In our laboratory three methods to analyze COHb in post-mortem blood samples were compared: the spectrophotometric method of Maehly, a gas chromatographic method with a thermal conductivity detector (GC-TCD) and the Oximeter. Several COHb containing blood samples of deceased persons were analyzed. Results of all three methods were comparable for low concentrations (ca. 10% COHb) as well as for high concentrations (ca. 80% COHb) regardless of the viscosity of the blood samples. The advantages of the Oximeter when compared to Maehly's method and GC-TCD are extreme short time of analysis (<1min), very small blood volume required (<0.1ml) and easy handling. In our opinion application of the Oximeter is not limited to analyses of blood samples from living persons (e.g. in clinical toxicology); it can as well be used for the determination of COHb in post-mortem blood samples. Hence it is a useful and time saving tool in forensic toxicology.     

Dating the writing age of black roller and gel inks by gas chromatography and UV-vis spectrophotometer

The relative and absolute age of roller and gel ink entries determined by gas chromatography (GC) and UV-vis methods are presented in this paper. The relative age of ink entries is concluded by the comparison of solvent amount between questioned and known dated entries. Absolute age of ink entries is estimated through the changing ratio of solvent components between heated and unheated samples without known samples for comparison. The methods are accurate and reliable.     

Forensic Applicability of Femur Subtrochanteric Shape to Ancestry Assessment in Thai and White American Males

Ancestry assessment from the postcranial skeleton presents a significant challenge to forensic anthropologists. However, metric dimensions of the femur subtrochanteric region are believed to distinguish between individuals of Asian and non‐Asian descent. This study tests the discriminatory power of subtrochanteric shape using modern samples of 128 Thai and 77 White American males. Results indicate that the samples' platymeric index distributions are significantly different (p ≤ 0.001), with the Thai platymeric index range generally lower and the White American range generally higher. While the application of ancestry assessment methods developed from Native American subtrochanteric data results in low correct classification rates for the Thai sample (50.8–57.8%), adapting these methods to the current samples leads to better classification. The Thai data may be more useful in forensic analysis than previously published subtrochanteric data derived from Native American samples. Adapting methods to include appropriate geographic and contemporaneous populations increases the accuracy of femur subtrochanteric ancestry methods.     

Classification of black powder toners on the basis of integrated analytical information provided by Fourier transform infrared spectrometry and X-ray fluorescence spectrometry

Differentiating between black powder toners used in laser printers and copiers can be challenging for forensic examiners. One hundred and sixty-two samples from 82 different types of cartridges produced by 21 manufacturers that are currently available on the Polish market were studied using Fourier transform infrared spectrometry (FT-IR) and energy-dispersive X-ray fluorescence spectrometry (XRF). The spectra obtained by these two methods were classified into 14 groups and 28 groups using FT-IR and XRF, respectively. These classifications served as a basis for the development of an analytical scheme for differentiating black powder toners. This scheme can be used with any two methods that supply different information about an examined sample. The research will show that if two samples are similar in polymer composition (e.g., FT-IR spectra), additional quantitative elemental composition from XRF analyses may provide more discrimination. It was possible to differentiate 82.5% pairs of examined samples using only FT-IR, 90.8% pairs of examined samples using only XRF, and 95.8% pairs of examined samples using these two methods. Obtained spectra and all the available information could be used to create/build a database. The results obtained confirm the multiplicity and compatibility of toners. Additionally, it was stated that not all the samples were original (OEM).