Commercially Available Blue Diode Laser Engraver Operating at 455 nm as an Affordable LD-REIMS Ionization Source

Area of Science:

• Analytical Chemistry
• Spectroscopy
• Biochemistry

Background:

• Lasers are widely used in mass spectrometry for ablation-desorption and ionization.
• Visible light lasers are less common for these applications.
• Lipid profiling is crucial for food analysis and authenticity.

Purpose of the Study:

• To investigate a visible light laser engraver as an ionization source for mass spectrometry.
• To optimize laser settings for analyzing biological tissues.
• To evaluate the potential of this method for food authenticity testing.

Main Methods:

• Utilized a 455 nm visible light laser engraver as an ionization source.
• Analyzed fresh salmon tissue samples, optimizing laser speed (300 mm/min) and power (30-50%).
• Compared spectral profiles and ion formation mechanisms with conventional Rapid Evaporation Ionization Mass Spectrometry (REIMS).

Main Results:

• Generated rich spectral profiles dominated by lipid species (fatty acids, glycerophospholipids).
• Observed spectral similarity to conventional REIMS, with slightly higher in-source fragmentation in the visible laser method.
• Successfully discriminated between Norwegian farmed salmon produced via conventional and organic methods.

Conclusions:

• A visible light laser engraver can serve as an effective ionization source for mass spectrometry-based lipid profiling.
• The method shows promise for food authenticity applications, as demonstrated by salmon sample discrimination.
• Further research can explore broader applications in food analysis and quality control.