A new approach for trace analysis of guanidine compounds in surface water with resorcinarene-based ion chromatography columns

Abstract

Trace levels of pharmaceuticals have been detected in surface water and may pose a health risk to humans and other organisms. New chromatographic materials will help identify and quantify these contaminants. We introduce a new ion chromatographic (IC) material designed to separate cationic pharmaceuticals and report its ability to separate a group of guanidine compounds. Guanidine moieties are strongly basic and protonated under acid conditions, and therefore can potentially be separated on the newly designed stationary phase and detected by ion exchange chromatography. The new column packing material is based on glutamic acids bonded to resorcinarene moieties that in turn are bound to divinylbenzene macroporous resin. Detection limits in the range of 5-30 μg L(-1) were achieved using integrated pulsed amperometric detection (IPAD) for guanidine (G), methylguanidine (MG), 1,1-dimethylbiguanide (DMG), agmatine (AGM), guanidinobenzoic acid (GBA) and cimetidine (CIM). Suppressed conductivity (CD) and UV-vis detection resulted in limits of detection similar to IPAD, in the range of 2-66 μg L(-1), but were not able to detect all of the analytes. Three water sources, river, lake, and marsh, were analyzed and despite matrix effects, sensitivity for guanidine compounds was in the 100 μg L(-1) range and apparent recoveries were 80-96%. The peak area precision was 0.01-2.89% for IPAD, CD and UV-vis detection.

Separation of perfluoroalkyl substances by ion chromatography with a resorcinarene stationary phase

“…The column was prepared by a similar procedure to previously reported columns [34]. To prepare the column, 0.14 g of RUE was dissolved in 25 ml THF and polystyrene packing resin (1.60 g) was added to the solution and mixed well.…”

Multifaceted Supramolecular Interactions from C‐Methylresorcin[4]arene Lead to an Enhancement in In Vitro Antibacterial Activity of Gatifloxacin

“…Resorcinarenes, closely related to the largely exploited calixarenes, represent a unique class of polyphenol macrocycles, which have potential use in supramolecular chemistry, catalysis, and separation science . An acid‐catalyzed condensation reaction between resorcinol and aldehyde gives a cyclic oligomer of C‐alkylresorcin[4]arene.…”

Guanidine Biosensors Enable Comparison of Cellular Turn-on Kinetics of Riboswitch-Based Biosensor and Reporter

“…However, the pathways toward guanidine accumulation and utilization in bacteria are still largely unknown. Beyond its biological importance, guanidine and its close derivatives are found as environmental pollutants or evidence of explosives. , As a contaminant, guanidine has been detected through spectroscopic methods such as UV and HPLC but these only work for in vitro samples. , Therefore, the development of a guanidine biosensor that can work both in the cell-free and cellular context will be significant for both environmental and biological applications.…”