On-line separation/analysis of Rhodamine B dye based on a solid-phase extraction high performance liquid chromatography self-designed device.

A special self-designed device based on poly-1-vinyl-3-pentylimidazole hexafluorophosphate (PILs-C) solid-phase extraction and high performance liquid chromatography (HPLC) is proposed as a novel method for the on-line separation and analysis of Rhodamine B (RhB) dye. Single factor experiment design and orthogonal experiment design were used to optimize the experimental parameters, such as pH, the amount of PILs-C, sample volume, flow rate, eluent type, eluent concentration, eluent volume, and the flow rate of eluent. Under the optimized conditions, the linear range was 0.02-2.4 μg mL, with the correlation coefficients ( ) of 0.997. The limit of detection (LOD) and limit of quantification (LOQ) were 0.004 μg mL and 0.02 μg mL, respectively. The extraction capacity was 6.22 mg g, and enrichment ratio was 15. The extraction mechanism and the post-treatment method of PILs-C were also studied. This method was applied to analyze RhB in a wide variety of real samples with satisfactory results.