Ostman Pekka, Luosujärvi Laura, Haapala Markus, Grigoras Kestas, Ketola Raimo A, Kotiaho Tapio, Franssila Sami, Kostiainen Risto
Department of Pharmaceutical Chemistry, Faculty of Pharmacy, P.O. Box 56, FIN-00014 University of Helsinki, Finland.
Anal Chem. 2006 May 1;78(9):3027-31. doi: 10.1021/ac052260a.
An atmospheric pressure chemical ionization (APCI) microchip is presented for combining a gas chromatograph (GC) to a mass spectrometer (MS). The chip includes capillary insertion channel, stopper, vaporizer channel, nozzle and nebulizer gas inlet fabricated on the silicon wafer, and a platinum heater sputtered on a glass wafer. These two wafers are joined by anodic bonding creating a two-dimensional version of an APCI microchip. The sample from GC is directed via heated transfer line capillary to the vaporizer channel of the APCI chip. The etched nozzle forms narrow sample plume, which is ionized by an external corona discharge needle, and the ions are analyzed by a mass spectrometer. The GC-microchip APCI-MS combination provides an efficient method for qualitative and quantitative analysis. The spectra produced by microchip APCI show intensive protonated molecule and some fragmentation products as in classical chemical ionization for structure elucidation. In quantitative analysis the GC-microchip APCI-MS showed good linearity (r(2) = 0.9989) and repeatability (relative standard deviation 4.4%). The limits of detection with signal-to-noise ratio of three were between 0.5 and 2 micromol/L with MS mode using selected ion monitoring and 0.05 micromol/L with MS/MS using multiple reaction monitoring.
本文介绍了一种用于将气相色谱仪（GC）与质谱仪（MS）联用的大气压化学电离（APCI）微芯片。该芯片包括在硅片上制造的毛细管插入通道、塞子、汽化器通道、喷嘴和雾化气入口，以及溅射在玻璃片上的铂加热器。这两个晶片通过阳极键合连接在一起，形成了二维的APCI微芯片。来自GC的样品通过加热的传输线毛细管导入到APCI芯片的汽化器通道中。蚀刻的喷嘴形成狭窄的样品羽流，该羽流由外部电晕放电针电离，离子由质谱仪进行分析。GC-微芯片APCI-MS联用提供了一种高效的定性和定量分析方法。微芯片APCI产生的光谱显示出强烈的质子化分子和一些碎片产物，如同经典化学电离用于结构解析一样。在定量分析中，GC-微芯片APCI-MS显示出良好的线性（r(2)=0.9989）和重复性（相对标准偏差为4.4%）。在选定离子监测的MS模式下，信噪比为3时的检测限在0.5至2微摩尔/升之间，在多反应监测的MS/MS模式下为0.05微摩尔/升。
