A simple microthermal desorption device

Area of Science:

• Analytical Chemistry
• Chromatography

Background:

• Traditional thermal desorption methods can be complex and require specialized equipment.
• Analyzing small samples, such as inks on paper, presents unique challenges in sample preparation and introduction.

Purpose of the Study:

• To present a simplified and cost-effective method for thermal desorption of small samples.
• To adapt existing solid phase microextraction (SPME) hardware for thermal desorption analysis.

Main Methods:

• Utilized a solid phase microextraction (SPME) holder with the fiber removed to contain small samples.
• Introduced samples directly into the gas chromatograph injector via the SPME holder needle.
• Performed thermal desorption at the injector temperature, without solvents or cryogenic cooling.

Main Results:

• Successfully analyzed ink samples on paper using the modified SPME holder.
• Determined an optimal desorption temperature of 200°C for ink samples, with minimal matrix interference.
• Demonstrated the method's compatibility with gas chromatography-flame ionization detection and gas chromatography-mass spectrometry.

Conclusions:

• The adapted SPME holder provides a cheap and efficient alternative for thermal desorption analysis of small samples.
• This method is suitable for laboratories lacking commercial thermal desorption devices.
• Applicable for analyzing various ink types on paper and potentially other small sample matrices.