Large-scale concordance study for 16 autosomal STRs analyzed with PowerPlex ESI17 and NGM SElect

This study aimed at identifying the frequency of kit-dependent discordances and genetic specialties in STR DNA typing, which is particularly important for the interpretation of DNA profiles as well as national and international database searches. We analyzed a total of 27′510 buccal swabs with the PowerPlex ESI 17 and NGM SElect amplification kits and documented discordances and other anomalies. We found kit-dependent full dropouts to be the most frequent events, most of which were associated with the NGM SElect kit. The total kit-dependent discordance rate determined in this study amounts to 0.74%. With this dataset, we also provide dropout rates, which can be used to estimate silent allele frequencies for 16 common STR loci amplified with the PowerPlex ESI17 and NGM SElect amplification kits.     

电喷雾和大气压化学法对大麻酚类物质离子化的比较

目的比较电喷雾电离(ESI)和大气压化学电离(APCI)两种模式对大麻酚类物质的离子化效果。方法采用UFLC-(ESI/APCI)MS分析方法,分别考察使用ESI和APCI时雾化电压、雾化气流量、干燥气流量、加热块温度、解离管温度等参数变化对大麻酚类物质的影响规律,确定最优条件参数组合,并比较ESI和APCI对大麻酚类物质的离子化效果。结果对于0.5μg/mL大麻二酚、大麻酚和四氢大麻酚标准品,ESI峰高分别为215 006、143 051、216 944,信噪比41.74、49.88、42.12,峰面积日内标准偏差(RSD)<3.96%;APCI峰高分别为140 238、226 505、247 753,信噪比78.37、131.03、138.46,峰面积日内标准偏差(RSD)<11.98%。结论检测大麻样品时,ESI为首选,基质复杂时可以使用APCI作为ESI的补充手段。     

Rapid Quantitative Analysis of Multiple Explosive Compound Classes on a Single Instrument via Flow‐Injection Analysis Tandem Mass Spectrometry

A flow‐injection analysis tandem mass spectrometry (FIA MSMS) method was developed for rapid quantitative analysis of 10 different inorganic and organic explosives. Performance is optimized by tailoring the ionization method (APCI/ESI), de‐clustering potentials, and collision energies for each specific analyte. In doing so, a single instrument can be used to detect urea nitrate, potassium chlorate, 2,4,6‐trinitrotoluene, 2,4,6‐trinitrophenylmethylnitramine, triacetone triperoxide, hexamethylene triperoxide diamine, pentaerythritol tetranitrate, 1,3,5‐trinitroperhydro‐1,3,5‐triazine, nitroglycerin, and octohy‐dro‐1,3,5,7‐tetranitro‐1,3,5,7‐tetrazocine with sensitivities all in the picogram per milliliter range. In conclusion, FIA APCI/ESI MSMS is a fast (<1 min/sample), sensitive (~pg/mL LOQ), and precise (intraday RSD < 10%) method for trace explosive detection that can play an important role in criminal and attributional forensics, counterterrorism, and environmental protection areas, and has the potential to augment or replace several of the existing explosive detection methods.     

生物质谱技术在法医遗传学中的应用展望

随着基质辅助激光解吸电离质谱 (MALDI MS)和电喷雾离子化质谱 (ESI MS)两种技术的迅速发展 ,生物质谱技术已经成为生命科学研究中的重要工具。由于直接检测分子的质量 ,质谱技术同其他方法相比更加准确。生物质谱技术在核酸序列分析中具有快速性、微量化、和高通量的特点。利用MALDI TOF MS技术可以分析降解检材的SNP遗传标记 ,这在法医学中将有着重要的意义。本文对生物质谱技术的原理、进展、面临的困难以及在法医遗传学中的应用前景作了评述