南京市某鸭血收购摊1份可疑样品成份应急检测

目的查明某鸭血收购摊1份可疑样品的主要成份。方法采用化学法、等离子发射光谱法和离子色谱法等技术手段对样品进行初筛,先后采用排除法、对照法及溶液中阴阳离子平衡理论进行推断,采用反相高效液相色谱法和离子色谱法进行定量检测。结果与国标检测方法进行比对,3种试验手段所测得的柠檬酸钠结果一致。溶液中柠檬酸钠的含量能够合理解释等离子发射光谱和离子色谱法测定溶液中钠元素、氯化物及硫酸根的含量。结论可疑样品为含有柠檬酸钠的溶液,并含有一定量有害的化学元素砷和铅等,对人体健康存在一定风险。     

原子吸收光谱仪以非原子化法测定醋酸氯己定

近年来 ,应用原子吸收光谱仪进行分子吸收测定 (即不须将样品原子化 )的研究工作有较大的进展 ,已在理论和技术上得到了证实。醋酸氯己定 ,是消毒防腐药 ,已报道的分析方法有紫外分光光度法、非水滴定法、气相色谱法、高效液相色谱法等[1 ,2 ] 。利用本法测定醋酸氯己定简便快捷 ,干扰少 ,所用试剂少。1　实验方法1 1　仪器原子吸收光谱仪 (日本岛津ＡＡ - 6 70 ) :在原子吸收光谱仪ＡＡ - 6 70上用锰空心阴极灯 2 79 5ｎｍ共振线 ,灯电流 5ｍＡ ,狭缝 0 4ｎｍ ,将自制比色杯架装在火焰燃烧器上 ,调节其位置 ,使光束通过吸收池中间位置。紫…     

Methylene Blue分光光度法与高效液相色谱法测定食品中糖精钠含量的比较研究

目的探讨和比较Methylene Blue分光光度法和高效液相色谱法测定食品中糖精钠含量的可靠性。方法 Methyl-ene Blue分光光度法以糖精钠磺酰基团与亚甲蓝和乙酸铜定量生成的蓝色络合物为定性指标,在656nm处进行比色测其吸光度。高效液相色谱法以:Luna5u-C18柱(250nm×4.6nm,10μm)为分析柱,以甲醇+1.54g/L醋酸铵溶液=15+85为流动相,流速1.0mL/min,检测波长为230nm。结果 Methylene Blue分光光度法,糖精钠在0~350μg/mL范围内线性关系良好(r=0.9976),最低检出限为0.006g/mL,加标回收率为99.651%~101.957%,变异系数为0.150%~0.660%。高效液相色谱法,糖精钠浓度为1~200μg/mL时,峰面积与浓度呈良好的线性关系(r=0.9997),最低检出限为0.004g/mL,加标回收率为99.908%~101.007%,变异系数为0.050%~0.430%。配对t检验统计结果表明Methylene Blue分光光度法和高效液相色谱法检测样品中糖精钠的含量差异无统计学意义。结论 Methylene Blue分光光度法和高效液相色谱法均能达到较好的准确度和精密度,可根据各自的实际条件选用不同的测定方法 。     

快速比色法检测花粉中总黄酮

花粉中总黄酮含量检测 ,对评价其功能作用具有一定的指导意义。黄酮类化合物的检测方法主要有高效液相色谱法和分光光度法 ,高效液相色谱法因仪器价格昂贵 ,不及分光光度法应用广泛。分光光度法利用黄酮类化合物与铝盐络合物在碱性溶液中显红色 ,而进行比色 ,样品前处理采用索氏提取 ,需 4～ 7ｈ ,很费时。利用黄酮类化合物的铝盐络合物本身具有的黄色进行比色 ,标准品的含量在 0～ 10 0 μｇ范围内 ,线性关系良好。本方法灵敏便快捷 ,用于实际样品的检测 ,取得满意的结果。本方法检出限为 2 5 μｇ。1　实验部分1 1　仪器　ＵＶ -12 0型紫…     

乙酰丙酮法测定腐竹中甲醛

甲醛的测定方法有高效液相色谱法、气相色谱法、分光光度法、示波极谱法等，我国至今没有制定国家的标准检测方法。卫生部推荐方法“乙酰丙酮分光光度法测定食品中甲醛次硫酸氢钠”尚存在不少问题。作者在应用该法对腐竹进行批量检测过程中总结了一些经验，尤其是对样品的前处理及样品的实验操作步骤进行了改进，同时对检测结果进行了比较，并作了初步分析探讨，现报告如下。     

生物材料中铅快速检测方法的研究进展

实验室常使用原子吸收分光光度法、原子吸收光谱法、原子荧光光谱法、气相色谱法、高效液相色谱法、生物传感器法等测定生物材料中铅的含量,这些方法大多操作烦琐、检测周期长,也有的方法操作条件不稳定、对实验要求高,难以满足应急检测工作的需求。快速检测方法具有操作简便、快速、仪器便于携带的特点,适合突发事件中疑似铅中毒人员的初筛检测及污染现场的应急处理。本文对生物样品中铅的快速检测方法的研究进展进行综述。     

食品中镁和钙检测方法的改进

目的建立同时检测食品中镁和钙的火焰原子吸收分光光度法。方法将样品湿消化后,以氯化镧溶液为释放剂,用火焰原子吸收分光光度法测定样品中镁和钙的含量。结果用改良后的方法检测标准物质,结果均在标准值范围内。方法精密度镁的RSD为2.40%,钙的RSD为2.54%。结论用氯化镧溶液代替氧化镧溶液作为释放剂,用火焰原子吸收分光光度法可同时测定食品中的镁和钙,方法简便准确,重复性好。     

用反相高效液相色谱法测定食品中苯甲酸、山梨酸和糖精钠

食品中防腐剂和甜味剂的测定方法有紫外分光光度法、气相色谱法及薄层色谱法等。国标检测方法有高效液相色谱法等。但国标法中,测定苯甲酸、山梨酸和糖精钠的高效液相色谱法中样品处理仅涉及汽水、果汁和配制酒类,而对于其他样品的处理方法没有提及。为建立一种快速测定食品中苯甲酸、山梨酸、     

高效液相色谱法测定工作场所空气中对苯二甲酸

目的建立高效液相色谱法测定工作场所空气中对苯二甲酸(PTA)的方法。方法按照《工作场所空气中毒物检测方法的研究规范》要求,对采样、精密度、回收率及样品的保存进行了系统的研究。用玻璃纤维滤纸对空气中气溶胶状态的PTA采样,1 g/L氢氧化钾溶液洗脱、高效液相色谱分离DAD检测。结果方法在1~10 mg/L及10~100 mg/L的浓度范围内均有良好的线性关系,相关系数分别为r=0.999 63及0.999 97,平均相对标准偏差小于5%(n=6),平均回收率为93.7%~98.8%,方法最低检出浓度为0.02 mg/L(S/N=3,进样量10μl),空气中的PTA的检出浓度为0.003 mg/m3(以采样体积75 L计算),为国家卫生标准的0.000 2倍。结论所建立的方法各项指标均符合有关要求,且优于紫外分光光度法,可以满足工作场所空气中PTA的时间加权平均浓度和短时间接触浓度的检测。     

非发酵性豆制品中脱氢乙酸的高效液相色谱测定法

目的通过实验摸索,建立高效液相色谱测定非发酵性豆制品中脱氢乙酸含量的方法。方法采用反向高效液相色谱法,以乙腈-0.02 mol/L磷酸二氢钾溶液等度洗脱,二极管阵列检测器检测。结果脱氢乙酸在1~50μg/ml浓度范围内线性良好,样品加标回收率为84.9%~102.6%,方法相对标准偏差(RSD)5%,方法最低定量限为0.002 g/kg。结论该方法前处理简单,检测灵敏度高,重现性好,适用于非发酵性豆制品中脱氢乙酸的检测。     

反滴定法测定静脉血样采集容器中抗凝剂组分EDTAK2含量

开发一种测定静脉血样采集容器中抗凝剂组分EDTAK2含量的化学分析方法,以替代仪器分析原子吸收分光光度计或渗透压仪。采用络合滴定的反滴定法,即以铬黑T做指示剂用氧化锌标准溶液滴定采血管中EDTAK2的含量,回收率可达到99%以上。     

高效液相色谱同时测定食品中5种添加剂

[目的]建立高效液相色谱(HPLC)同时测定食品中安赛蜜、糖精钠、苯甲酸、山梨酸和阿斯巴甜的方法。[方法]样品经去蛋白、脱色、超声提取、过滤膜等预处理,采用HPLC二极管分段多波长同时测定。[结果]方法线性良好,相关系数为0.9995~0.9999,回收率为90.70%~98.20%,相对标准偏差为0.41%~2.40%。[结论]方法准确可靠、简便快速、易于掌握、便于推广。     

面粉、面制品中过氧化苯甲酰的测定及还原剂的选择

目的在推荐方法的基础上改进并建立高效液相色谱法测定面粉及面制品中过氧化苯甲酰的方法。方法以乙腈-0.01mol/L醋酸铵溶液为流动相,优化色谱分离条件,选择合适的还原剂碘化钾溶液浓度,并以碘化钾溶液的还原能力做对照,比较五种实验室常用还原剂对过氧化苯甲酰的还原效率及色谱分离情况。结果在选择的分离条件下,以10%碘化钾做还原剂,方法的线性范围为0.01mg～0.15mg,最低检出量为0.8ng,相关系数大于0.9996,平均加标回收率介于92.4%～105.3%之间,相对标准偏差为2.3%～4.3%。10%亚硫酸氢钠、10%硫代硫酸钠、10%亚铁氰化钾均可作为转化反应的还原剂。结论所建立的方法灵敏度高,分离效果好。实验室人员可根据情况选择适当的还原剂。     

Simultaneous determination of urinary creatinine and metabolites of toluene,xylene, styrene,ethylbenzene and phenol by automated high performance liquid chromatography

Summary An attempt was made to establish a method for the direct determination of urinary concentrations of creatinine, hippuric acid, methylhippuric acid and mandelic acid by automated high performance liquid chromatography (HPLC). Urine was diluted with distilled water or mobile phase, then the mixture was centrifuged and the supernatant was injected into HPLC. A stainless-steel column packed with octadecyl silanized silicate was used, and the mobile phase was a solution of [20 mM potassium phosphate monobasic containing 3 mM sodium 1-decanesulfonate]/acetonitorile (85/15). Another HPLC method for the determination of urinary concentration of phenol, metabolites of benzene and/or phenol is also described. Phenyl sulfate and phenyl glucuronide in urine were hydrolyzed enzymatically into phenol. The hydrolyzed mixture was injected into HPLC with the ODS column. The mobile phase was a solution of [20 mM potassium phosphate monobasic containing 1 mM sodium 1-decanesulfonate]/acetonitorile (85/15). The ratio of hippuric acid (HA) concentration to creatinine concentration determined by the urine of students after physical exercise was similar to that before exercise. Moreover, the coefficient of correlation found between the toluene concentration in a workshop and the HA concentration in workers' urine, corrected for creatinine, was higher than that obtained between the toluene concentration and the uncorrected HA concentration. For assays on stored urine samples, urine was spotted on filter paper, dried and kept several weeks, and then MA, HA, o-MHA, m-MHA and creatinine in the filter paper were eluted with 50% methanol and their concentrations determined by HPLC.     

高效液相色谱测定食品中环己基氨基磺酸钠的提取方法研究

目的通过对多类食品中环己基氨基磺酸钠(甜蜜素)测定的样品前处理技术和测定方法的研究,建立简便、快速、适用的食品中甜蜜素的高效液相色谱测定方法。方法选用30%乙醇提取样品中的甜蜜素。提取液中的甜蜜素与次氯酸钠反应生成N,N-二氯环己胺,经正己烷提取,用高效液相色谱测定。结果食品中甜蜜素在0～2.00 mg/ml范围内,浓度与峰面积呈直线相关关系;方法最低检出量为0.02μg;最低检出浓度为0.005 0 g/kg。对浓度为0.097～5.6g/kg的样品连续测定6次,RSD为1.1%～6.0%;加标量为0.20～2.0 g/kg的样品,回收率为85%～106%。结论该方法简便、快速、精密、准确,适用于食品中甜蜜素含量的测定。     

Sodium and potassium excretion in a sample of normotensive and hypertensive persons in eastern Finland.

A 24-hour urine collection was carried out during a cardiovascular survey in eastern Finland. The study population comprised 148 hypertensive subjects in a random sample of the middle-aged population and 86 normotensive controls. The mean sodium excretion was 197 mmol/24h in both normotensive and hypertensive men, 179 mmol/24h in normotensive women, and 174 mmol/24h in hypertensive women. There were no significant differences in potassium excretion rate or in sodium: potassium molar ratio between the normotensive and the hypertensive among either men or women. There was no statistically significant correlation between blood pressure level and sodium or potassium excretion or sodium: potassium molar ratio. One in four of the subjects reported that they usually added salt to their food before tasting it. The results of this study show that the average level of salt intake in a Finnish population is high, and so is the sodium: potassium molar ratio. Although there was no correlation between sodium excretion and blood pressure levels, it is known that in this population the average blood pressure level is high and cardiovascular disease extremely frequent.     

Relation between urinary beta-aminoisobutyric acid excretion and concentration of lead in the blood of workers occupationally exposed to lead.

Urinary beta-aminoisobutyric acid (ABA) concentration was determined by fluorometric high performance liquid chromatography in 22 workers occupationally exposed to lead. The urinary excretion of ABA was increased with increasing exposure to lead. The excretion of urinary ABA had a significant correlation with concentration of lead in blood (Pb-B) (r = 0.581), similar to the correlation of Pb-B with urinary delta-aminolaevulinic acid (ALA) concentration (r = 0.563). The determination of urinary ABA concentration in workers exposed to lead, therefore, may offer a new approach for evaluating the health effect of lead.     

A solid sorbent air sampling and analytical procedure for methyl-, dimethyl-, ethyl-, and diethylamine

A sampling and analytical procedure for methyl-, dimethyl-, ethyl-, and diethylamine was developed in order to avoid problems typically encountered in the sampling and analysis of low molecular weight aliphatic amines. Samples are collected with adsorbent tubes containing Amberlite XAD-7 resin coated with the derivatizing reagent, NBD chloride (7-chloro-4-nitrobenzo-2-oxa-1,3-diazole). Analysis is performed by high performance liquid chromatography with the use of a fluorescence and/or UV/visible detector. All four amines can be monitored simultaneously, and neither collection nor storage is affected by humidity. Samples are stable at room temperature for at least two weeks. The methodology has been tested for each of the four amines at sample loadings equivalent to air concentration ranges of 0.5 to 30 ppm for a sample volume of 10 liters. The method shows promise for determining other airborne primary and secondary low molecular weight aliphatic amines.     

颅脑外伤后血浆渗透压变化分析的临床现状

[目的]探讨颅脑外伤后患者血浆渗透压水平变化的临床意义。[方法]回顾性分析某院神经外科2007年10月～2010年10月期间收治的125例颅脑外伤患者的临床资料,根据入院格拉斯哥评分将患者分为3组,分别测定患者血浆渗透压、血钠、血糖及血尿素氮,比较3组患者血浆渗透压水平,并对血浆渗透压与血钠、血糖及血尿素氮进行线性回归分析,患者出院时按GOS进行疗效判定,分析血浆渗透压与疾病预后的关系。[结果]患者颅脑外伤病情越严重,血浆渗透压越高,且血浆渗透压水平与血钠、血糖、血尿素氮呈正性相关,住院期间死亡、重残及植物生存状态患者的血浆渗透压水平显著高于治愈及中残患者,差异均有统计学意义(P﹤0.05)。[结论]颅脑外伤患者血浆渗透压水平可作为反映疾病严重程度的客观指标,监测其变化可作为患者病情变化和判断预后的可靠指标,临床上可通过纠正或改善患者血浆渗透压改善患者预后。     

氨基酸分析仪法测定胶原类硬脑膜补片中羟脯氨酸含量

目的:建立一种用氨基酸分析仪测定胶原类硬脑膜补片中羟脯氨酸(Hypro)含量的测定方法。方法:样品采用6mol.L-1盐酸水解处理22h后,用氨基酸分析仪,采用离子交换色谱茚三酮柱后衍生后对羟脯氨酸进行分析,以外标法测定含量。流动相:pH=3.3的柠檬酸钠缓冲液-0.2mol.l-1氢氧化钠溶液梯度洗脱,检测波长为440 nm,流速0.4 ml.min-1。结果:羟脯氨酸在浓度3.06~612μg.mL-1范围内呈良好的线性关系(r=1.0),RSD=0.13%(n=6),加样回收率(n=6)为98.05%(RSD=1.4%)。结论:该方法测定羟脯氨酸操作简便、快速、准确,具有良好的重复性和稳定性,且不受其他氨基酸干扰,可用于胶原类硬脑膜补片产品中羟脯氨酸含量的检测和质量控制。