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Infrared laser ablation sampling coupled with data independent high resolution UPLC-IM-MS/MS for tissue analysis

Infrared laser ablation sampling coupled with data independent high resolution UPLC-IM-MS/MS for tissue analysis
M. E. Pettit, F. Donnarumma, K. K. Murray, & T. Solouki, Analytica Chimica Acta in Press, DOI: 10.1016/j.aca.2018.06.066

Infrared laser ablation sampling coupled with data independent high resolution UPLC-IM-MS/MS for tissue analysis DOI: 10.1016/j.aca.2018.06.066
Infrared laser ablation sampling coupled with data independent high resolution UPLC-IM-MS/MS for tissue analysis

Infrared laser ablation microsampling was used with data-dependent acquisition (DDA) and ion mobility-enhanced data-independent acquisition (HDMSE) for mass spectrometry based bottom-up proteomics analysis of rat brain tissue. Results from HDMSE and DDA analyses of the 12 laser ablation sampled tissue sections showed that HDMSE consistently identified approximately seven times more peptides and four times more proteins than DDA. To evaluate the impact of ultra-performance liquid chromatography (UPLC) peak congestion on HDMSE and DDA analysis, whole tissue digests from rat brain were analyzed at six different UPLC separation times. Analogous to results from laser ablated samples, HDMSE analyses of whole tissue digests yielded about four times more proteins identified than DDA for all six UPLC separation times.

Infrared laser ablation and capture of enzymes with conserved activity

Wang, K., Donnarumma, F., Baldone, M. D., & Murray, K. K. Infrared laser ablation and capture of enzymes with conserved activity. Anal Chim Acta, 1027, 41–46 (2018).

Graphical abstract: Infrared laser ablation and capture of enzymes with conserved activity
Graphical abstract: Infrared laser ablation and capture of enzymes with conserved activity

Abstract

Infrared (IR) laser ablation at 3 μm wavelength was used to extract enzymes from tissue and quantitatively determine their activity. Experiments were conducted with trypsin, which was ablated, captured and then used to digest bovine serum albumin (BSA). BSA digests were evaluated using matrix-assisted laser desorption ionization (MALDI) mass spectrometry (MS) and sequence coverage of 59% was achieved. Quantification was performed using trypsin and catalase standards and rat brain tissue by fluorescence spectroscopy. Both enzymes were reproducibly transferred with an efficiency of 75 ± 8% at laser fluences between 10 and 30 kJ/m2. Trypsin retained 37 ± 2% of its activity and catalase retained 50 ± 7%. The activity of catalase from tissue was tested using three consecutive 50 μm thick rat brain sections. Two 4 mm2 regions were ablated and captured from the cortex and cerebellum regions. The absolute catalase concentration in the two regions was consistent with previously published data, demonstrating transfer of intact enzymes from tissue.

Droplet Capture Tip-enhanced Laser Ablation Sampling for Mass Spectrometry

WP 394
Droplet Capture Tip-enhanced Laser Ablation Sampling for MS
WP 394: Droplet Capture Tip-enhanced Laser Ablation Sampling for Mass Spectrometry
WP 394: Droplet Capture Tip-enhanced Laser Ablation Sampling for Mass Spectrometry
Fan Cao, "Droplet Capture Tip-enhanced Laser Ablation Sampling for Mass Spectrometry", American Society for Mass Spectrometry National Meeting, San Diego, June 3-7, 2018
Fan Cao, “Droplet Capture Tip-enhanced Laser Ablation Sampling for Mass Spectrometry”, American Society for Mass Spectrometry National Meeting, San Diego, June 3-7, 2018

Contact:  Fan Cao 
More Information:  Tip-enhanced Laser Ablation 

Forensic Sampling Using Gas-pulse Displacement and Vacuum Capture

WP278: Forensic Sampling Using Gas-pulse Displacement and Vacuum Capture
WP278: Forensic Sampling Using Gas-pulse Displacement and Vacuum Capture
Jamira Stephenson, "Forensic Sampling Using Gas-pulse Displacement and Vacuum Capture" American Society for Mass Spectrometry National Meeting, San Diego, June 3-7, 2018
Jamira Stephenson, “Forensic Sampling Using Gas-pulse Displacement and Vacuum Capture” American Society for Mass Spectrometry National Meeting, San Diego, June 3-7, 2018
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