Automated surface sampling and imaging systems under ambient conditions

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OAK RIDGE NATIONAL LABORATORYU. S. DEPARTMENT OF ENERGY

Automated surface sampling and imaging systems under ambient conditions

Automated DESI and SSP

Vilmos Kertesz and Gary J. Van Berkel

10/17/2006

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Goal: MS friendly interface for automated surface sampling and imaging systems

Systems: Self-aspirating surface sampling probe (SSP, ORNL patent) Desorption ElectroSpray Ionization (DESI)

Requirements: Implement support for different surface analysis methods:

imaging, line scanning, spot sampling, array sampling Support different MS instruments Provide REAL-TIME data visualization (chemical image of the

surface for multiple m/z, XIC chromatograms) Implement signal optimization automatism

(microjunction/capillary-to-surface distance optimization for SSP/DESI, respectively)

MS-information-rich software interface

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Parts

• MS: sprayer and extended sampling capillary (DESI), self-aspirating probe (SSP)

• computer with MS and HandsFree TLC/MS software installed

• XYZ stage to move the sample

• color cameras, digital camera, capture devices and monitors for visualization and monitoring

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Features• Automated line scanning, imaging, spot and array sampling

• Corresponding X-Y-time-MS spectrum data structure (full scan, SIM, MRM, etc.)

• High-resolution photo showing the analyzed surface stored inside the data file with the X-Y-time-MS spectrum data

• Automated probe(SSP)/capillary(DESI)-to-surface distance control for optimum MS signal

• REAL-TIME MS image for multiple ions (made possible via real-time communication with Analyst and LCQTune)

• REAL-TIME XIC chromatograms for multiple ions

• REAL-TIME MS on screen

• Display/analyze MS of selected, already-analyzed, area WHILE acquiring new data

• Powerful post-processing features (image manipulation, MS analysis, ion maps)

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Main screen – during data acquisition Parameter settings

Image

Camera picture for surface distance control

Actual MS

Average MS of selected area (if any)

XICs

XIC settings

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Post-processing MS image (over the photo of the surface)

Image manipulation (ion, color scheme, interpolation etc.)

Ion map for selecting ions to display their image

XIC of selected ions

Individual MSs of selected area (if any)

Sum MS of selected area (if any)

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Imaging – click on the picture to start movie

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Array sampling – click on the picture to start movie