MALDI-TOF and MALDI-FTICR imaging mass spectrometry of methamphetamine incorporated into hair

✍ Scribed by Akihiro Miki; Munehiro Katagi; Tooru Kamata; Kei Zaitsu; Michiaki Tatsuno; Toyofumi Nakanishi; Hitoshi Tsuchihashi; Takayuki Takubo; Koichi Suzuki

• Publisher: John Wiley and Sons
• Year: 2011
• Tongue: English
• Weight: 281 KB
• Volume: 46
• Category: Article
• ISSN: 1076-5174
• DOI: 10.1002/jms.1908

✦ Synopsis

Abstract

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’. Copyright © 2011 John Wiley & Sons, Ltd.