Method and system for desorption electrospray ionization

An ionization and desorption technology, applied in the field of analytes in ionized sample materials, can solve problems such as problems that have not been overcome

Inactive Publication Date: 2007-11-14
PURDUE RES FOUND INC
View PDF0 Cites 60 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

[0010] Despite recent advances in the ionization of materials for mass spectrometry, there are still a number of issues that have not been overcome on the path to wider commercial use of these techniques

Method used

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
View more

Image

Smart Image Click on the blue labels to locate them in the text.
Viewing Examples
Smart Image
  • Method and system for desorption electrospray ionization
  • Method and system for desorption electrospray ionization
  • Method and system for desorption electrospray ionization

Examples

Experimental program
Comparison scheme
Effect test

Embodiment 1

[0060] The promise of the DESI device and method for forensic and public safety applications such as detection of explosives and chemical agents on environmental (uncontrolled) surfaces is illustrated here by two experiments. In one experiment the explosive RDX was desorbed from the surface of an insulating tanned leather (pig) to give 1 ng / mm 2 Negative ion DESI spectrum of RDX (Fig. 3(a)), using acetonitrile (CAN) / methanol (MeOH) / trifluoroacetic acid (TFA) 1:1:0.1% as solvent. The presence of this explosive in the spectrum was confirmed by tandem MS (inset).

Embodiment 2

[0062] In a second experiment, nitrile gloves were exposed to dimethyl methylphosphonate vapor (DMMP is a chemical weapons irritant) for less than a second, then washed and dried, giving a mass spectrum, shown in Figure 3(b), Clearly shows the presence of traces of DMMP. The positive ion DESI spectrum of DMMP was obtained using acetonitrile (ACN) / methanol (MeOH) / trifluoroacetic acid (TFA) 1:1:0.1% as solvent. Examples 1 and 2 also demonstrate that the DESI-active spray includes species that can react with the sample in such a way that a measurable ionic species of the reaction product is formed and desorbed.

Embodiment 3

[0064] Hemlock (Conium maculatum) seeds were dissected and placed in the apparatus in Figure 1 under ambient conditions. Methanol / water was used to generate a DESI-active spray that was sprayed onto the seeds, and the desorbed ions were transferred to an ion trapping mass spectrometer. Figure 4(a) shows the resulting positive DESI ion spectrum. The signal at m / z 126 corresponds to protonated γ-coniceine (molecular weight 125), an alkaloid present in plants. The DESI-active spray and rod-shaped ion collection lines used to move ionized and desorbed species to the mass spectrometer were scanned across a length of hemlock stem. Figure 4(b) shows the intensity distribution at m / z 126 across the entire stem cross-section. The DESI-active spray was also scanned across a portion of the tomato skin, and the resulting ionized species were collected and introduced to the ion-trapping MS through metal ion transport tubes. The resulting spectrum is shown in Figure 4(c).

[0065] Quant...

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to view more

PUM

No PUM Login to view more

Abstract

A new method and system for desorption ionization is described and applied to the ionization of various compounds, including peptides and proteins present on metal, polymer, and mineral surfaces. Desorption electrospray ionization (DESI) is carried out by directing charged droplets and / or ions of a liquid onto the surface to be analyzed. The impact of the charged particles on the surface produces gaseous ions of material originally present on the surface. The resulting mass spectra are similar to normal ESI mass spectra in that they show mainly singly or multiply charged molecular ions of the analytes. The DESI phenomenon was observed both in the case of conductive and insulator surfaces and for compounds ranging from nonpolar small molecules such as lycopene, the alkaloid coniceine, and small drugs through polar compounds such as peptides and proteins. Changes in the solution that is sprayed can be used to selectively ionize particular compounds, including those in biological matrices. In vivo analysis is demonstrated.

Description

[0001] related application [0002] This application claims Provisional Application No. 60 / 558352 filed March 30, 2004; Provisional Application No. 60 / 611934 filed September 21, 2004; Provisional Application No. 60 / 612100 filed September 22, 2004 ; Provisional Application No. 60 / 627526, filed November 12, 2004; Provisional Application No. 60 / 630365, filed November 23, 2004; and Provisional Application No. 60 / 643650, filed January 9, 2005 priority. field of invention [0003] The present invention relates generally to the field of ionizing analytes in sample materials, and more particularly, to ionizing analytes in sample materials under ambient or controlled conditions at atmospheric pressure, identifying ionized analytes by chemical analysis, and , if desired, imaging the source of the ionized analyte. Background technique [0004] The development of desorption ionization techniques may have provided the first breakthrough in the mass spectrometric analysis of fragile non...

Claims

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to view more

Application Information

Patent Timeline
no application Login to view more
Patent Type & Authority Applications(China)
IPC IPC(8): H01J27/00
Inventor Z·塔卡特斯B·戈洛干J·M·维塞曼R·G·库克斯
Owner PURDUE RES FOUND INC
Who we serve
  • R&D Engineer
  • R&D Manager
  • IP Professional
Why Eureka
  • Industry Leading Data Capabilities
  • Powerful AI technology
  • Patent DNA Extraction
Social media
Try Eureka
PatSnap group products