Quantitative determination of plant hormones and derivatives in biogas slurry using on-line solid phase extraction with high performance liquid chromatography (On-Line SPE HPLC)

Abstract

A novel method using on-line solid phase extraction coupled with high performance liquid chromatography (On-line SPE HPLC) was developed to measure three important plant hormones and two indole derivatives in the biogas slurry. These measured substances include abscisic acid (ABA), gibberellins (GA), indoleacetic acid (IAA), tryptophan (TRP) and skatole (IMD), respectively. This method could continuously perform extraction of ABA, GA, IAA, TRP and IMD from different concentrations of biogas slurry samples without complicated pretreatment avoiding lost, and then the extracts were analyzed by high performance liquid chromatography (HPLC). After optimized the analytical condition, a baseline separation of three plant hormones and two indole derivatives was accomplished within 35 mins. The results showed excellent linearity (R2 values of 0.9930-0.9999) and intra- and inter-day precisions (in the range of 3.8-7.2% and 3.9-7.5%), respectively. The limits of detection and quantification were in the range of 0.16-0.47 μg·mL-1 and 0.53-1.57 μg·mL-1, respectively. The determination performance was satisfactory with the proposed method. The results showed that the developed method was suitable for analysis of trace plant hormones in the biogas slurry.