Deep-ultraviolet laser ablation sampling for proteomic analysis of tissue

Area of Science:

• Biochemistry
• Proteomics
• Laser Technology

Background:

• Spatially resolved proteomic analysis requires precise tissue sampling.
• Traditional methods may cause protein fragmentation or loss during extraction.
• Deep-ultraviolet (DUV) laser ablation offers a potential solution for targeted tissue analysis.

Purpose of the Study:

• To evaluate the efficacy of 193 nm ArF excimer laser ablation for intact protein extraction from tissue sections.
• To determine the efficiency and yield of protein capture using DUV laser ablation.
• To compare DUV laser ablation with infrared laser ablation for proteomic analysis.

Main Methods:

• Localized tissue regions were ablated using a 193 nm ArF excimer laser.
• Captured proteins were analyzed for integrity using MALDI-TOF MS and quantified via Bradford assay.
• Extracted proteins were digested and analyzed by liquid chromatography tandem mass spectrometry (LC-MS/MS).

Main Results:

• DUV laser ablation successfully captured intact bovine serum albumin (BSA) without fragmentation.
• Protein transfer efficiency reached 90% at a laser fluence of 3 kJ/m².
• DUV laser ablation yielded approximately four times more identified proteins and greater protein mass compared to infrared laser ablation.

Conclusions:

• 193 nm ArF excimer laser ablation is an effective method for spatially resolved proteomic analysis.
• This technique preserves protein integrity and significantly improves protein identification yields.
• DUV laser ablation represents a superior approach for deep tissue sampling in proteomics.