Direct determination of volatile analytes from solid samples by UV-ion mobility spectrometry.

Area of Science:

• Analytical Chemistry
• Spectrometry

Background:

• Accurate determination of volatile analytes in solid matrices is crucial for quality control and safety.
• Existing methods for volatile compound analysis can be complex and time-consuming.

Purpose of the Study:

• To develop and validate a simple, reliable, and inexpensive sample introduction system (SIS) for volatile analyte determination in solid samples.
• To couple the SIS with ion mobility spectrometry (IMS) for direct analysis.
• To assess the performance of the SIS-IMS method for quantifying specific volatile amines and ammonia.

Main Methods:

• A novel sample introduction system (SIS) was designed for direct introduction of solid samples (e.g., fish) into an ion mobility spectrometry (IMS) setup.
• Volatile analytes were released from the sample by heating (75°C for 5 min) after NaOH addition.
• Analytes permeated through a membrane into a nitrogen stream and were subsequently analyzed by UV-IMS.
• Method validation included linearity, repeatability, reproducibility, and analyte recovery studies.

Main Results:

• The SIS-IMS method demonstrated linearity over a concentration range of 5-225 µg mL⁻¹.
• High repeatability (RSD < 4%) and reproducibility (RSD < 9%) were achieved.
• Acceptable analyte recoveries (111 ± 17%) were obtained for spiked fish samples.
• The system successfully determined volatile analytes including trimethylamine, dimethylamine, and ammonia.

Conclusions:

• The developed SIS-IMS method is a rapid, cost-effective, and efficient approach for the qualitative and quantitative analysis of volatile compounds in solid samples.
• The system requires minimal sample pretreatment, making it suitable for routine analysis.
• Ion mobility spectrometry shows significant potential for direct analysis of volatile analytes in complex matrices.