Forensic Science Laboratory, Osaka Prefectural Police Headquarters 1-3-18 Hommachi, Chuo-ward, Osaka 541-0053, Japan.
J Mass Spectrom. 2011 Apr;46(4):411-6. doi: 10.1002/jms.1908.
A new approach is described for imaging mass spectrometry (IMS) of methamphetamine (MA) incorporated into human hair using matrix-assisted laser desorption/ionization (MALDI)-time-of-flight (TOF) and MALDI-Fourier transform ion cyclotron resonance (FTICR). A longitudinal section of a lengthwise manually-cut single human hair shaft from a chronic MA user was directly analyzed by MALDI-TOF-IMS after deposited with α-Cyano-4-hydroxycinnamic acid matrix. A barcode-like image, which was most probably generated with repeated intakes of MA, was for the first time obtained by monitoring MA-specific product ion in the selected reaction monitoring mode. Laser beam scan lengthwise-cut hair shafts gave only poor mass spectra of MA, probably due to the loss of MA and/or the thermal denaturation of hair. The identity of MA detected in hair was further confirmed by MALDI-FTICR mass spectrometry. A combination with ultra-high resolution mass spectrometry by FTICR provided indisputable identification of MA. The MALDI-FTICR-IMS of another hair shaft from the same MA user also provided a barcode-like image by monitoring the protonated molecule of MA with ultra-high resolution. The two barcode-like images exhibited a close resemblance. Thus, MALDI-IMS can offer a new perspective: 'imaging hair analyses for drugs'.
一种新的方法被描述用于成像质谱法（IMS）对甲安非他命（MA）在人类头发中的应用，使用基质辅助激光解吸/电离（MALDI）-飞行时间（TOF）和 MALDI-傅里叶变换离子回旋共振（FTICR）。对一个慢性 MA 用户的人工纵向切割的单个头发轴的纵向部分，在沉积α-氰基-4-羟基肉桂酸基质后，直接通过 MALDI-TOF-IMS 进行分析。通过在选择反应监测模式下监测 MA 特异性产物离子，首次获得了可能是由于反复摄入 MA 而产生的条码样图像。沿激光束扫描的纵向切割的头发轴只能得到 MA 的较差的质谱，这可能是由于 MA 的损失和/或头发的热变性所致。通过 MALDI-FTICR 质谱法进一步证实了头发中检测到的 MA 的身份。FTICR 的超高分辨率质谱与 MALDI-FTICR 的结合提供了 MA 的无可争议的鉴定。来自同一 MA 用户的另一个头发轴的 MALDI-FTICR-IMS 也通过监测 MA 的质子化分子提供了一个条码样图像，具有超高分辨率。两个条码样图像非常相似。因此，MALDI-IMS 可以提供一个新的视角：“成像头发分析毒品”。
