Desorption electrospray ionization of explosives on surfaces:: Sensitivity and selectivity enhancement by reactive desorption electrospray ionization

被引:284
作者
Cotte-Rodríguez, I [1 ]
Takáts, Z [1 ]
Talaty, N [1 ]
Chen, HW [1 ]
Cooks, RG [1 ]
机构
[1] Purdue Univ, Dept Chem, W Lafayette, IN 47907 USA
关键词
D O I
10.1021/ac050995+
中图分类号
O65 [分析化学];
学科分类号
070302 ; 081704 ;
摘要
Desorption electrospray ionization (DESI), an ambient mass spectrometry technique, is used for trace detection of the explosives trinitrohexahydro-1,3,5-triazine (RDX), octahydro-1,3,5,7-tetranitro-1,3,5,7-tetrazocine (HMX), 2,4,6-trinitrotoluene (TNT), Pentaerythritol tetranitrate (PETN), and their plastic compositions (Composition C-4, Semtex-H, Detasheet) directly from a wide variety of surfaces (metal, plastic, paper, polymer) without sample preparation or pretreatment. Analysis of the explosives is performed under ambient conditions from virtually any surface in very short times (< 5 s) including confirmatory tandem mass spectrometry (MS/MS) experiments, while retaining the sensitivity and specificity that mass spectrometry offers. Increased selectivity is obtained both by MS/MS and by performing additional experiments in which additives are included in the spray solvent. These reactive DESI experiments (reactions accompanying desorption) produce such ions as the chloride and trifluoroacetate adducts of RDX and HMX or the Meisenheimer complex of TNT. Desorption atmospheric pressure chemical ionization, a variant of DESI that uses gas-phase ions generated by atmospheric pressure corona discharges of toluene or other organic compounds, provides evidence for a heterogeneous-phase (gaseous ion/absorbed analyte) charge-transfer mechanism of DESI ionization in the case of explosives. Plastic explosives on surfaces were analyzed directly as fingerprints, without sample preparation, to test DESI as a possible method for in situ detection of explosives-contaminated surfaces. DESI also allowed detection of explosives in complex matrixes, including lubricants, household cleaners, vinegar, and diesel fuel. Absolute limits of detection for the neat explosives were subnanogram in all cases and subpicogram in the case of TNT. The DESI response was linear over 3 orders of magnitude for TNT. Quantification of RDX on paper gave a precision (RSD) of 2.3%. Pure water could be used as the spray solution for DESI, and it showed ionization efficiencies for RDX in the negative ion mode similar to that given by methanol/water. DESI represents a simple and rapid way to detect explosives in situ with high sensitivity and specificity and is especially useful when they are present in complex mixtures or in trace amounts on ordinary environmental surfaces.
引用
收藏
页码:6755 / 6764
页数:10
相关论文
共 56 条
[1]  
[Anonymous], 1993, EXPLOSIVES
[2]  
Asbury GR, 2000, TALANTA, V50, P1291
[3]   COLLISIONS OF FLUOROCARBON IONS AT SOLID-SURFACES - ELECTRONIC EXCITATION, SURFACE-INDUCED DISSOCIATION AND CHEMICAL SPUTTERING [J].
AST, T ;
RIEDERER, DE ;
MILLER, SA ;
MORRIS, M ;
COOKS, RG .
ORGANIC MASS SPECTROMETRY, 1993, 28 (10) :1021-1033
[4]  
BOARD NMA, 2004, OPPORTUNITIES IMPROV
[5]   DESORPTION IONIZATION MASS-SPECTROMETRY [J].
BUSCH, KL .
JOURNAL OF MASS SPECTROMETRY, 1995, 30 (02) :233-240
[6]   Rapid multivariate curve resolution applied to identification of explosives by ion mobility spectrometry [J].
Buxton, TL ;
Harrington, PD .
ANALYTICA CHIMICA ACTA, 2001, 434 (02) :269-282
[7]   CHARACTERIZATION OF EXPLOSIVES BY LIQUID-CHROMATOGRAPHY MASS-SPECTROMETRY AND LIQUID-CHROMATOGRAPHY TANDEM MASS-SPECTROMETRY USING ELECTROSPRAY-IONIZATION AND PARENT-ION SCANNING TECHNIQUES [J].
CASETTA, B ;
GAROFOLO, F .
ORGANIC MASS SPECTROMETRY, 1994, 29 (10) :517-525
[8]   The mechanism for unimolecular decomposition of RDX (1,3,5-trinitro-1,3,5-triazine), an ab initio study [J].
Chakraborty, D ;
Muller, RP ;
Dasgupta, S ;
Goddard, WA .
JOURNAL OF PHYSICAL CHEMISTRY A, 2000, 104 (11) :2261-2272
[9]   Reduction of nitroaromatics to arylnitrenium ions by vinyl halide cations [J].
Chen, H ;
Zheng, XB ;
Yang, PX ;
Cooks, RG .
CHEMICAL COMMUNICATIONS, 2004, (06) :688-689
[10]   Meisenheimer complexes bonded at carbon and at oxygen [J].
Chen, H ;
Chen, HW ;
Cooks, RG .
JOURNAL OF THE AMERICAN SOCIETY FOR MASS SPECTROMETRY, 2004, 15 (07) :998-1004