将电喷雾解吸电离质谱(DESI-MS)用于临床尿样的分析,优化了电喷雾溶剂流速、电喷雾电压和喷雾锥距离等重要参数.采用普通滤纸作为样品载体,在不需要样品预处理的前提下同时快速测定了临床尿样中的钾、钠、尿素、尿酸、丙酮酸和肌苷等多...将电喷雾解吸电离质谱(DESI-MS)用于临床尿样的分析,优化了电喷雾溶剂流速、电喷雾电压和喷雾锥距离等重要参数.采用普通滤纸作为样品载体,在不需要样品预处理的前提下同时快速测定了临床尿样中的钾、钠、尿素、尿酸、丙酮酸和肌苷等多种成分,并对各种成分的主要离子进行了串联质谱鉴定.DESI-MS在进行多组分同时测定时不需要进行样品预处理,缩短了测定时间,单个样品的分析时间不到1 m in.同时,采用内标法对所测定组分进行了半定量分析.展开更多
A direct determination method for the atrazine residue on the vegetable was developed by using desorption electrospray ionization mass spectrometry (DESI MS) without any sample pretreatment.Acetonitrile-water (1:1,v/v...A direct determination method for the atrazine residue on the vegetable was developed by using desorption electrospray ionization mass spectrometry (DESI MS) without any sample pretreatment.Acetonitrile-water (1:1,v/v),which contained 0.1% formic acid,was used as the spray solvent.The working conditions,such as ESI gas inlet pressure,ESI flow rate,ESI spray voltage,spray-to-sample distance,spray-to-cone-hole distance and the collision induced dissociation (CID) voltage for MS/MS,were optimized for both DESI and esquires 6 000 mass spectrometer.The linear range of atrazine on cabbage leaves was 25.25-2 525 pg/mm2,the R2 was 0.991 6,and the relative standard deviations were between 3.37% and 26.17%.The LOD of atrazine calculated by S/N=3 was 2.50 pg/mm2.展开更多
文摘目的:通过解吸电喷雾电离质谱成像(desorption electrospray ionization-mass spectrometry imaging,DESI-MSI)研究口腔鳞状细胞癌(oral squamous cell carcinomas,OSCC)的潜在生物标志物和可能的代谢途径。方法:本研究纳入的10例OSCC病例均为在江苏大学附属医院口腔颌面外科就诊住院且接受手术治疗的原发病例。收集组织样本用于DESI-MSI检测,进一步采用多元及单变量统计分析筛选差异代谢物,然后用受试者工作特征曲线(receiver operating characteristic curve,ROC曲线)分析差异代谢物的诊断能力。最后,进行京都基因和基因组百科全书(Kyoto Encyclopedia of Genes and Genomes,KEGG)代谢通路分析确定相关的代谢通路。结果:OSCC肿瘤组织与正常组织共鉴定出144种差异代谢物,大多数为脂肪酸。ROC曲线分析发现这144种代谢物曲线下的面积(area under the curve,AUC)值均大于0.7。KEGG代谢通路分析发现,与OSCC发生相关的通路为不饱和脂肪酸的生物合成以及脂肪酸的生物合成。结论:基于DESI-MSI筛选了具有诊断价值的差异代谢物,发现OSCC组织存在不饱和脂肪酸的生物合成以及脂肪酸的生物合成代谢紊乱,可能与OSCC的发生发展密切相关。
文摘将电喷雾解吸电离质谱(DESI-MS)用于临床尿样的分析,优化了电喷雾溶剂流速、电喷雾电压和喷雾锥距离等重要参数.采用普通滤纸作为样品载体,在不需要样品预处理的前提下同时快速测定了临床尿样中的钾、钠、尿素、尿酸、丙酮酸和肌苷等多种成分,并对各种成分的主要离子进行了串联质谱鉴定.DESI-MS在进行多组分同时测定时不需要进行样品预处理,缩短了测定时间,单个样品的分析时间不到1 m in.同时,采用内标法对所测定组分进行了半定量分析.
文摘A direct determination method for the atrazine residue on the vegetable was developed by using desorption electrospray ionization mass spectrometry (DESI MS) without any sample pretreatment.Acetonitrile-water (1:1,v/v),which contained 0.1% formic acid,was used as the spray solvent.The working conditions,such as ESI gas inlet pressure,ESI flow rate,ESI spray voltage,spray-to-sample distance,spray-to-cone-hole distance and the collision induced dissociation (CID) voltage for MS/MS,were optimized for both DESI and esquires 6 000 mass spectrometer.The linear range of atrazine on cabbage leaves was 25.25-2 525 pg/mm2,the R2 was 0.991 6,and the relative standard deviations were between 3.37% and 26.17%.The LOD of atrazine calculated by S/N=3 was 2.50 pg/mm2.
