分光光度法同时测定人发中的钙、锌

将多元线性回归分析用于分光光度法同时测定人发中钙、锌元素的含量,讨论了该方法的原理,考察了最佳实验条件,建立了回归方程和线性方程。对6个模拟发样和2个人发样品进行了测定,结果令人满意。     

极谱配合吸附波法同时测定人发锌、铅、铜与评价

本文介绍用极谱配合吸附波方法同时快速测定人发中的锌、铅、铜,并着重研究了人发样品的预处理方法。对青岛市区各不同年龄组健康者与厌食症儿童发样测定的统计分析结果进行了评价。     

微波消解-超声雾化-ICP-AES测定发样中微量元素

研究了微波消解-超声雾化-ICP-AES测定人发样品中12种常量、微量元素的方法。对样品的测定条件进行了优化，并对20例女性拉祜族长寿老人发样进行了测定。与普通老人比较，女性拉祜族长寿老人发样中Mn、Mo、Ge的含量均明显高于普通老人发样中含量，存在显著性差异。     

高频感耦等离子体光谱法测定人发中铁、锰、铬、铜、钛和锌等元素的研究

人发微量元素分析在医学,环境科学,法医学等方面具有极其重要的意义。ICP-AES法具有快速简便,检测极限低,精密度高,干扰少,多元素同时测定等优点,用于人发中微量元素的分析具有突出的优越性,本文研究了ICP-AES摄谱法同时测定发样中铁、锰、铬、铜、釱、锌的最优化条件,拟定了测定方法,取得了满意的结果。实验部分 (一)仪器与试剂 1.ICP装置:GP_(3.5)-D_1型高频发生器。功率3.5KW,频率35MHz,耦合线圈φ6mm紫铜     

分光光度法同时测定人发中的钙,锌

将多元线性回归分析用于分光光度法同时测定人发中钙，锌元素的含量，讨论了该方法的原理，考察了最佳实验条件，建立了回归方程和线性方程。对６人模拟发样和２个人发样品进行了测定，结果令人满意。     

2，3-二氨基萘荧光光度法测定楚雄地区糖尿病患者发硒含量

采用2,3-二氨基萘荧光光度法测定了楚雄地区糖尿病患者发硒含量,选取糖尿病患者50例,健康人群30例进行测定。结果表明,楚雄地区糖尿病患者发样中硒含量总体平均值为（0．3052±0．1263）μg/g,健康人群发样中硒含量总体平均值为（0．3345±0．1512）μg/g,糖尿病患者发样中硒含量明显低于健康人群,差异有统计学意义。     

极谱络合吸附催化波测定人发中微量锗的研究

用Ｇｅ（Ⅳ）－邻苯二酚－溴酸钠极谱络合吸附催化波测定人发中微量锗，并对发样的消化处理方法进行了较详细的研究，测定结果令人满意。     

精神发育迟滞儿童的头发微量元素检测及分析

为测定和分析精神发育迟滞儿童头发微量元素营养状态,选择来自某特殊学校学生（IQ均低于70）210例发样为观察组,采用原子吸收分光光度法测定发样中锌、铁、铜、钙、锰、铅、镁和铬含量.结果表明,本组210例精神发育迟滞儿童的发铅和发镁低于正常对照组,具有统计学意义.发锌稍高于对照组但无统计学意义,其它几种元素含量基本相似.可见特殊学校精神发育迟滞儿童的发铅和发镁比正常儿童低,其意义值得进一步分析.     

溶剂萃取——火焰原子吸收法测定人发中微量钴

钴是人体中必需的微量元素之一.据报道,心血管疾病和白癜风患者与体内长期缺乏微量钴有关.文献〔2」已报道了测定头发中微量钴的吸光光度法和石墨炉原子吸收光谱法.本工作采用硝酸一过氧化氢湿法消化发样,然后用二乙基二硫代氨基甲酸钠(DDTC)络合、MIBK萃取钴,空气-乙炔火焰原子吸收法测定.方法的重现性好、灵敏度高,发样中的共存元素无明显干扰,是测定人发中微量钴较为满意的方法.     

人发的光谱分析进展

评述了用分光光度、荧光（原子荧光）、原子吸收、原子发射光谱方法进行人发中我种元素测定的分析（包括发样采集、洗涤、消化），引用文献９６篇。     

Time-of-flight secondary ion mass spectrometry analysis of hair from archaeological remains

Hair from four individuals excavated from burial sites in Pacatnamu, Peru from the Moche (450-800 AD) and Lambayeque (900-1100 AD) periods was sectioned longitudinally and analysed with time-of-flight secondary ion mass spectrometry (ToF-SIMS). An attempt was made to distinguish biogenic and diagenetic contributions to the elemental concentrations in the hair samples. Significant contamination was observed to have penetrated the hair samples from the burial environment. Results from the analyses indicate that the burial environment plays an important role in the postmortem variation in elemental content of hair samples. Various elements demonstrated an ability to permeate through the hair matrix over time. In addition, NaCl and what are believed to be aluminosilicates and mineral sulphates, were observed to have accumulated on the surface of the samples. Degradation of the samples was also suspected due to the presence of molecular fragments, possibly resulting from oxidation of the keratin proteins. The results should assist in the identification of reliable elemental signals in the analysis of ancient hair samples and promote caution when considering elements that are abundant in the burial environment.     

Simultaneous quantification of morphine and cocaine in hair samples from drug addicts by GC-EI/MS

The development of analytical techniques that enable the use of hair as an alternative matrix for the analysis of drugs of abuse is useful for confirming the exposure in a larger time window (weeks to months, depending on the length of the hair shaft). In the present study a methodology aimed at the simultaneous quantification of cocaine and morphine in human hair was developed and validated. After decontamination, hair samples (20?mg) were incubated with a mixture of methanol/hydrochloric acid (2:1) at 65?°C overnight (~16?h) in order to extract the drugs of the matrix. Purification was performed by solid-phase extraction using mixed-mode extraction cartridges. After derivatization with N-methyl-N-(trimethylsilyl) trifluoroacetamide, blank, standards and samples were analyzed by gas chromatography/electron impact-mass spectrometry (GC-EI/MS). The method proved to be selective, as there were no interferences of endogenous compounds with the same retention time as cocaine, morphine and ethylmorphine (internal standard). The regression analysis for both analytes showed linearity in the range 0.25-10.00?ng/mg with correlation coefficients ranging from 0.9989 to 0.9991. The coefficients of variation oscillated between 0.83 and 14.60%. The limits of detection were 0.01 and 0.02?ng/mg, and the limits of quantification were 0.03 and 0.06?ng/mg for cocaine and morphine, respectively. The proposed GC-EI/MS method provided an accurate and simple assay with adequate precision and recovery for the quantification of cocaine and morphine in hair samples. The proof of applicability was performed in hair samples obtained from drug addicts enrolled in a Regional Detoxification Treatment Center. The importance of hair samples is highlighted, since positives results were obtained when urine immunoassay analyses were negative. Copyright ? 2012 John Wiley & Sons, Ltd.     

Analysis of anabolic steroids in hair by GC/MS/MS

A simple and sensitive gas chromatography/tandem mass spectrometry (GC/MS/MS) method is described for the detection of anabolic steroids, usually found in keratin matrix at very low concentrations. Hair samples from seven athletes who spontaneously reported their abuse of anabolic steroids, and in a single case cocaine, were analyzed for methyltestosterone, nandrolone, boldenone, fluoxymesterolone, cocaine and its metabolite benzoylecgonine. Anabolic steroids were determinate by digestion of hair samples in 1 m NaOH for 15 min at 95 degrees C. After cooling, samples were purificated by solid-phase and liquid-liquid extraction, then anabolic steroids were converted to their trimethylsilyl derivative and finally analyzed by GC/MS/MS. For detection of cocaine and benzoylecgonine, hair samples were extracted with methanol in an ultrasonic bath for 2 h at 56 degrees C then overnight in a thermostatic bath at the same temperature. After the incubation, methanol was evaporated to dryness, and benzoylecgonine was converted to its trimethylsilyl derivative prior of GC/MS/MS analysis. Results obtained are in agreement with the athletes' reports, confirming that hair is a valid biological matrix to establish long-term intake of drugs.     

Sensitive analysis of anti-HIV drugs, efavirenz, lopinavir and ritonavir, in human hair by liquid chromatography coupled with tandem mass spectrometry

A highly sensitive and selective method using liquid chromatography coupled with tandem mass spectrometry (LC/MS/MS) was developed and validated for the measurement of three antiretroviral agents, efavirenz, lopinavir and ritonavir, in human hair. Hair samples from adherent HIV-infected patients on antiretroviral therapies were cut into about 1 mm length segments and drugs were extracted by first shaking the samples with methanol in a 37 degrees C water bath overnight (>14 h), followed by methyl tert-butyl ether/ethyl acetate (1:1) extraction under weak alkaline conditions. The extracted lopinavir and ritonavir were separated by reversed-phase chromatography and detected by tandem mass spectrometry in electrospray positive ionization mode with multiple reaction monitoring (MRM), while efavirenz was monitored in negative ionization MRM mode. This method was validated from 0.01 to 4.0 ng/mg hair for ritonavir and 0.05-20 ng/mg hair for lopinavir and efavirenz by using 2 mg of a human hair sample. The interday and intraday assay precision (coefficients of variation, CV) for spiked quality control (QC) samples at low, medium and high concentrations were within 15% and accuracy ranged from 89% to 110%. Assay reproducibility was also demonstrated by analysis of incurred hair QC samples (CV <14%). No significant matrix ionization suppression was observed. This developed method allowed for the monitoring of these target medications in the hair samples of HIV-infected women on antiretroviral therapy in an observational study using small amounts of hair.     

Analysis of ethyl glucuronide and ethyl sulfate using aqueous normal‐phase chromatography with mass spectrometry

The use of aqueous normal‐phase chromatography is explored as a possible format for the analysis of the forensically significant compounds ethyl glucuronide and ethyl sulfate. Standard solutions of the two compounds are used to verify the retention capabilities of two stationary phases (diamond hydride and undecanoic acid). These results are then compared to data obtained on hair extracts to determine if any matrix effects exist with respect to both retention and peak shape. The undecanoic stationary phase is used for the establishment of calibration curves for quantitative analysis. These curves are utilized to determine the concentration of ethyl glucuronide in several hair samples tested.     

Application of carbon nanotubes modified with a Keggin polyoxometalate as a new sorbent for the hollow‐fiber micro‐solid‐phase extraction of trace naproxen in hair samples with fluorescence spectrophotometry using factorial experimental design

A sensitive technique to determinate naproxen in hair samples was developed using hollow‐fiber micro‐solid‐phase combined with fluorescence spectrophotometry. The incorporation of multi‐walled carbon nanotubes modified with a Keggin polyoxometalate into a silica matrix prepared by the sol–gel method was reported. In this research, the Keggin carbon nanotubes /silica composite was used in the pores and lumen of a hollow fiber as the hollow‐fiber micro‐solid‐phase extraction device. The device was used for the microextraction of the analyte from hair and water samples under the optimized conditions. An orthogonal array experimental design with an OA24 (4⁶) matrix was employed to optimize the conditions. The effect of six factors influencing the extraction efficiency was investigated: pH, salt, volume of donor and desorption phase, extraction and desorption time. The effect of each factor was estimated using individual contributions as response functions in the screening process. Analysis of variance was employed for estimating the main significant factors and their contributions in the extraction. Calibration curve plot displayed linearity over a range of 0.2–10 ng/mL with detection limits of 0.072 and 0.08 ng/mL for hair and aqueous samples, respectively. The relative recoveries in the hair and aqueous matrices ranged from 103–95%. The relative standard deviation for fiber‐to‐fiber repeatability was 3.9%.     

A fast screening MALDI method for the detection of cocaine and its metabolites in hair

Matrix-assisted laser desorption/ionisation (MALDI) mass spectrometry was used for the rapid detection of cocaine, benzoylecgonine and cocaethylene in hair. Different MALDI sample preparation procedures have been tested and the employment of a multi-layer 'graphite-sample-electrosprayed alpha-cyano-4-hydroxycinnamic acid (HCCA)' yielded the best results for standard solutions of the target analytes. The same approach was subsequently applied to hair samples that were known to contain cocaine, benzoylecgonine and cocaethylene, as determined by a classical GC-MS method. It was however necessary to extract hair samples by incubating them in methanol/trifluoroacetic acid for a short time (15 min) at 45 degrees C; 1 microl of the obtained supernatant was deposed on a metal surface treated with graphite, and HCCA was electrosprayed on it. This procedure successfully suppressed matrix peaks and was effective in detecting all the target analytes as their protonated species. The results obtained give further confirmation of the effectiveness of the MALDI for detecting drugs and their metabolites in complex biological matrices. The method can be useful as a fast screening procedure to detect the presence of cocaine and metabolites in hair samples.     

Application of an ETV-ICP system for the determination of elements in human hair

When determining element contents in hair samples without sample digestion it is necessary to analyze large sample volumes in order to minimize problems of inhomogeneity of biological sample materials. Therefore an electrothermal vaporization system (ETV) is used for solid sample introduction into an inductively coupled plasma (ICP) for the determination of matrix and trace elements in hair. This paper concentrates on the instrumental aspects without time consuming sample preparation. The results obtained for optimization tests, ETV operating parameters and ICP operating parameters, are shown and discussed. Standard additions are used for calibration for the determination of Zn, Mg, and Mn in human hair. Studies including reproducibility and detection limits for chosen elements have been carried out on certified reference materials (CRMs). The determination of reproducibility (relative standard deviation (RSD) of n = 10) and detection limits (DLs) of Zn (RSD < 8.5%, DL < 0.8 μ g⁻¹), Mn (RSD < 14.1%, DL < 0.3 μ g⁻¹), and Mg (RSD < 7.4%, DL < 6.6 μ g⁻¹) are satisfactory. The concentration values found show good agreement with the corresponding certified values. Further sample preparation steps, including hair sampling, washing procedure and homogenization for hair, relating to measurements of real hair samples are described.     

Development and validation of an analytical method for the simultaneous determination of cocaine and its main metabolite, benzoylecgonine, in human hair by gas chromatography/mass spectrometry

A new, simple and rapid procedure has been developed and validated for the determination of cocaine and its main metabolite, benzoylecgonine, in human hair samples. After extraction from within the hair matrix by a mixture of methanol/hydrochloric acid (2:1) at 65 degrees C for 3 h, and sample cleanup by mixed-mode solid-phase extraction (SPE), the extracts were analyzed by gas chromatography/mass spectrometry (GC/MS), after derivatization with N-methyl-N-(trimethylsilyl)trifluoroacetamide with 5% chlorotrimethylsilane. Using a sample size of only 20 mg of hair, limits of detection (LODs) and quantitation (LOQs) were, respectively, 20 and 50 pg/mg for cocaine, and 15 and 50 pg/mg for benzoylecgonine, achieving the cut-off values proposed by the Society of Hair Testing for the analysis of these compounds in hair. The method was found to be linear (weighing factor of 1/x) between the LOQ and 20 ng/mg for both compounds, with correlation coefficients ranging from 0.9974 to 0.9996 for cocaine; and from 0.9981 to 0.9994 for benzoylecgonine. Intra- and interday precision and accuracy were in conformity with the criteria normally accepted in bioanalytical method validation. The sample cleanup step presented a mean absolute recovery greater than 90% for both compounds. The developed method may be useful in forensic toxicology laboratories for the analysis of cocaine and benzoylecgonine in hair samples, taking into account its speed (only 3 h are required for the extraction of the analytes from within the matrix, whereas 5 h or even overnight extractions have been reported) and the low limits achieved (using a single quadrupole mass spectrometer, which is available in most laboratories).     

Development of extraction methods for the analysis of perfluorinated compounds in human hair and nail by high performance liquid chromatography tandem mass spectrometry

Perfluorinated compounds (PFCs) are ubiquitous in the environment and are becoming a public health concern. It is desirable to develop sensitive and accurate methods to measure PFCs in non-invasive matrices such as hair and nail for biomonitoring of body burden. Different extraction methods coupled with solid phase extraction were investigated for extraction efficiency. The extracts were separated, identified and quantified by liquid chromatography-tandem mass spectrometry. Extraction with acetonitrile proved to be the most efficient extraction method for human hair sample, while extraction by methanol with alkaline digestion performed best for human nail sample. The matrix recoveries of the optimized methods ranged from 78% to 116% for hair and from 87% to 126% for nail sample. The ranges of the limit of detection (LOD) were 0.026–0.069 ng/g and 0.023–0.094 ng/g for hair and nail, respectively. These methods were validated by evaluating LOD, accuracy and precision and were proven to be useful for measuring paired human hair and nail samples collected from the general population.