Determination of diethylenetriamine in workplace air by HPLC based on adsorption on alkaline silica gel tubes and derivatization-desorption

Objective To establish a method for the determination of diethylenetriamine (DETA) in workplace air by alkaline silica gel tube adsorption-derivatization desorption-high performance liquid chromatography (HPLC), and to evaluate its application efficacy.

Methods Drawing on existing HPLC detection technologies, alkaline silica gel tubes were utilized for both long-term and short-term sampling, followed by subsequent analysis. The method was systematically characterized in terms of its linear range, precision, accuracy, desorption efficiency, stability, and anti-interference performance.

Results The method exhibited a linear concentration range of 0.19-30 μg/mL with a linear correlation coefficient (r)>0.999, indicating excellent linearity. Under the conditions of a sampling volume of 7.5 L and a desorption solution volume of 2 mL, the limit of detection (LOD) was 0.015 mg/m³, and the limit of quantification (LOQ) was 0.051 mg/m³. The average desorption efficiency ranged from 92.1% to 98.5%, with a relative standard deviation (RSD) of 2.81%-5.03%. Spike recovery rates were 91.66%-102.67%, and the samples showed stability for at least 15 days at room temperature. For experimental atmospheres prepared at 0.5× and 2× the permissible concentration-time weighted average (PC-TWA), the sampling efficiency was 91.9%-100.0%.

Conclusion The developed method of alkaline silica gel tube adsorption-derivatization desorption-HPLC for DETA in workplace air demonstrates high responsiveness, good precision, and short analysis time. It enables standardized operation from sampling to analysis, yielding accurate and reliable results, and is thus suitable for the determination of DETA in workplace air and large-scale occupational health monitoring.