Ensuring selectivity using retention time modulation by solvent composition, applied to the analysis of phenol in...

Area of Science:

• Analytical Chemistry
• Environmental Science
• Forensic Chemistry

Background:

• E-liquids contain volatile contaminants and aroma compounds.
• Accurate quantification of phenol in e-liquids is challenging due to matrix complexity.
• Existing methods struggle with selectivity for phenol in complex e-liquid matrices.

Purpose of the Study:

• To develop and validate a gas chromatographic method for determining volatile contaminants and phenol in e-liquids.
• To overcome selectivity issues in phenol detection caused by high concentrations of aroma compounds.
• To establish a reliable method for phenol confirmation in e-liquid samples.

Main Methods:

• Gas chromatography coupled with tandem mass spectrometry (GC-MS/MS) was employed.
• A novel approach involving the addition of 1,2-propanediol to the injection solvent was introduced.
• Method validation included assessment of working range (0.01–0.5 mg/l) and coefficients of variation (2–14%).

Main Results:

• The method demonstrated sufficient selectivity for most volatile contaminants.
• Phenol detection was initially hindered by interfering aroma compounds.
• Addition of 1,2-propanediol effectively shifted phenol's retention time, enabling reliable confirmation without affecting interferents.
• Validated working range: 0.01–0.5 mg/l; variation coefficients: 2–14%.

Conclusions:

• A robust GC-MS/MS method for analyzing volatile contaminants in e-liquids was successfully developed and validated.
• The novel 1,2-propanediol addition technique provides an effective solution for phenol detection in complex e-liquid matrices.
• This approach enhances chromatographic selectivity and offers reliable phenol confirmation without additional instrumentation.