KIT Researchers Identify Molecular Hydration as Key Factor for Removing Glyphosate and AMPA From Water

KIT researchers discover how molecular hydration shells and pH levels influence the removal of glyphosate and AMPA from water using nanofiltration technology.

By: AXL Media

Published: Apr 30, 2026, 9:43 AM EDT

Source: Information for this report was sourced from EurekAlert!

A Scientific Breakthrough in Herbicide Filtration Dynamics

The persistent presence of glyphosate and its primary metabolite, aminomethylphosphonic acid, in the global water cycle has necessitated a shift toward more sophisticated purification technologies. Researchers at the Karlsruhe Institute of Technology, specifically within the Institute for Advanced Membrane Technology, have identified a critical third variable in the effectiveness of nanofiltration. Beyond the established mechanical constraints of molecular size and electrical charge, the team discovered that the hydration shell, a layer of water molecules surrounding the contaminant, dictates how easily these toxins are captured. This development addresses the urgent need for robust treatment systems as agricultural runoff continues to impact biodiversity and human health.

The Persistence of Metabolites in Environmental Systems

The scope of the investigation extended to aminomethylphosphonic acid, commonly referred to as AMPA, which is a byproduct formed as glyphosate breaks down in soil. While glyphosate is the most utilized herbicide globally, AMPA presents a distinct challenge because it shares similar chemical characteristics but possesses a significantly longer environmental lifespan. To tackle these resilient substances, the Karlsruhe team collaborated with international partners from Poland, the Czech Republic, and Germany. According to Professor Andrea Iris Schäfer, the study’s corresponding author, the removal of these pollutants is a complex interaction between the physical pores of the membrane and the liquid environment surrounding each individual molecule.

Technical Mechanics of Advanced Nanofiltration Membranes

Nanofiltration operates as a pressure-driven purification method where membrane pores are measured in just a few nanometers. These systems traditionally function through two primary mechanisms: a physical sieve that blocks larger molecules and an electrical repulsion system that pushes away ions with a similar charge. The recent research adds a layer of sophistication by focusing on how molecules appear to the membrane based on their attached water molecules. These hydration shells effectively increase the perceived size of the glyphosate, influencing whether a molecule can slip through or is successfully retained by the filtration barrier.