Background: Gamma-glutamyltransferase is recognised as a biomarker to assess the harms associated with alcohol misuse. The objective ways to measure GGT in areas lacking central lab facilities are desirable. This stud...Background: Gamma-glutamyltransferase is recognised as a biomarker to assess the harms associated with alcohol misuse. The objective ways to measure GGT in areas lacking central lab facilities are desirable. This study aims to measure GGT from dried serum spots and its storage from dried serum spots. Method: The study was approved by the institutional ethical committee. One hundred and eighty (180) patients were included in the study. Their blood samples were collected. The serum samples were spotted onto filter paper (Whatman 903) dried and stored at 4°C. The GGT levels were measured on the day of collection and at various time periods to assess the effect of storage. All the analysis was performed on SPSS version 21. Result: The GGT levels measured from fresh serum GGT levels mean (SD) 286.5 (539.4) correlated well with their respective dried serum levels 287.18 (538.2) (P = 0.80). The mean recovery of GGT from dried serum was observed to be 103.3%. A sub-sample (n = 12) was stored at 4°C. The dried serum spots were found to be stable at the end of four weeks using repeated measure analysis of variance (ANOVA) (P = 0.39). Conclusion: This method has the potential to be used for epidemiological or field based studies to assess harms associated with alcohol use.展开更多
建立了一步式QuEChERS自动提取和净化技术结合气相色谱-串联质谱同时测定风干牦牛肉中15种N-亚硝胺的分析方法。样品水化后,经乙腈提取,加入4.0 g MgSO_(4)和1.0 g NaCl除水,经十八烷基硅烷(C_(18))和N-丙基乙二胺(PSA)填料净化,采用DB-...建立了一步式QuEChERS自动提取和净化技术结合气相色谱-串联质谱同时测定风干牦牛肉中15种N-亚硝胺的分析方法。样品水化后,经乙腈提取,加入4.0 g MgSO_(4)和1.0 g NaCl除水,经十八烷基硅烷(C_(18))和N-丙基乙二胺(PSA)填料净化,采用DB-HeavyWAX色谱柱(30 m×0.25 mm×0.25μm)分离15种N-亚硝胺,在多重反应监测(MRM)模式下进行测定,外标法定量。结果表明,15种N-亚硝胺分离性能良好,在0.1~200μg/L范围内线性关系良好,相关系数(r^(2))≥0.999 0;检出限(LOD)为0.05~0.20μg/kg,定量限(LOQ)为0.10~0.50μg/kg;在1倍、2倍和10倍LOQ 3个添加水平下的平均回收率分别为79.4%~102.1%、80.6%~109.5%、83.0%~110.6%,相对标准偏差(RSD)为0.8%~16.0%。应用建立的方法检测2种不同加工工艺的市售样品,其中7种N-亚硝胺类化合物(N-亚硝基二甲胺、N-亚硝基二异丁胺、N-亚硝基二正丁胺、N-亚硝基甲基苯胺、N-亚硝基乙基苯胺、N-亚硝基吡咯烷、N-亚硝基二苯胺)均有不同程度检出,平均含量为0.08~20.18μg/kg,且熟制风干牦牛肉中N-亚硝胺的检出率和平均含量均高于传统生制风干牦牛肉。该方法实现了前处理的自动化,相较于其他传统方法,操作简单,实验效率高,人为影响因素小,检测灵敏度高,适用于风干牦牛肉中15种N-亚硝胺的快速测定,为研究肉制品中N-亚硝胺的测定提供了方法支持。展开更多
文摘Background: Gamma-glutamyltransferase is recognised as a biomarker to assess the harms associated with alcohol misuse. The objective ways to measure GGT in areas lacking central lab facilities are desirable. This study aims to measure GGT from dried serum spots and its storage from dried serum spots. Method: The study was approved by the institutional ethical committee. One hundred and eighty (180) patients were included in the study. Their blood samples were collected. The serum samples were spotted onto filter paper (Whatman 903) dried and stored at 4°C. The GGT levels were measured on the day of collection and at various time periods to assess the effect of storage. All the analysis was performed on SPSS version 21. Result: The GGT levels measured from fresh serum GGT levels mean (SD) 286.5 (539.4) correlated well with their respective dried serum levels 287.18 (538.2) (P = 0.80). The mean recovery of GGT from dried serum was observed to be 103.3%. A sub-sample (n = 12) was stored at 4°C. The dried serum spots were found to be stable at the end of four weeks using repeated measure analysis of variance (ANOVA) (P = 0.39). Conclusion: This method has the potential to be used for epidemiological or field based studies to assess harms associated with alcohol use.
文摘建立了一步式QuEChERS自动提取和净化技术结合气相色谱-串联质谱同时测定风干牦牛肉中15种N-亚硝胺的分析方法。样品水化后,经乙腈提取,加入4.0 g MgSO_(4)和1.0 g NaCl除水,经十八烷基硅烷(C_(18))和N-丙基乙二胺(PSA)填料净化,采用DB-HeavyWAX色谱柱(30 m×0.25 mm×0.25μm)分离15种N-亚硝胺,在多重反应监测(MRM)模式下进行测定,外标法定量。结果表明,15种N-亚硝胺分离性能良好,在0.1~200μg/L范围内线性关系良好,相关系数(r^(2))≥0.999 0;检出限(LOD)为0.05~0.20μg/kg,定量限(LOQ)为0.10~0.50μg/kg;在1倍、2倍和10倍LOQ 3个添加水平下的平均回收率分别为79.4%~102.1%、80.6%~109.5%、83.0%~110.6%,相对标准偏差(RSD)为0.8%~16.0%。应用建立的方法检测2种不同加工工艺的市售样品,其中7种N-亚硝胺类化合物(N-亚硝基二甲胺、N-亚硝基二异丁胺、N-亚硝基二正丁胺、N-亚硝基甲基苯胺、N-亚硝基乙基苯胺、N-亚硝基吡咯烷、N-亚硝基二苯胺)均有不同程度检出,平均含量为0.08~20.18μg/kg,且熟制风干牦牛肉中N-亚硝胺的检出率和平均含量均高于传统生制风干牦牛肉。该方法实现了前处理的自动化,相较于其他传统方法,操作简单,实验效率高,人为影响因素小,检测灵敏度高,适用于风干牦牛肉中15种N-亚硝胺的快速测定,为研究肉制品中N-亚硝胺的测定提供了方法支持。