A biocompatible and recyclable ionic liquid platform for long-term and high temperature plant RNA stabilization

RNA is a fundamental biomolecule essential to life with diverse and expanding functional roles. The inherent instability and high susceptibility of RNA to degradation during sampling, handling, and storage limit the reliability of RNA-based analyses. Elevated temperature conditions accelerate degradation and compromise RNA quality for downstream applications. Ionic liquids (ILs) have shown significant promise in stabilizing short-chain and commercially-available RNA. There is a critical need for stabilization platforms that protect more complex and heterogenous RNA systems, such as total plant RNA across a broad range of temperature conditions, while maintaining biocompatibility and enabling recyclability.

In this study, choline-based aqueous IL solutions were evaluated to develop a biocompatible and reusable platform for stabilization of total plant RNA. Among the different ILs tested, 20% (w/v) choline glutamate emerged as the most effective stabilization medium which hindered RNA degradation during short-term handling at higher temperature and extended storage at 40 °C and ambient temperature. Immediate stabilization preserved RNA integrity at levels statistically comparable to RNA controls. Upon heating, control RNA degraded at 70 °C and higher, whereas RNA stored in choline glutamate IL retained higher integrity even at 80-90 °C, indicating significant suppression of thermal degradation. Long-term studies demonstrated higher RNA integrity for at least 72 h at 40 °C and delayed degradation by several weeks at room temperature. The IL was recycled and reused for at least five cycles without compromising RNA integrity or purity, representing a significant advancement in green analytical chemistry.

This work introduces an IL-based platform specifically designed for stabilizing complex, heterogeneous total plant RNA. By identifying choline glutamate as an effective medium, this study advances the field toward a practical, scalable preservation strategy that operates across a wide temperature range and supports long-term storage, including conditions relevant to field sampling and transport. The integration of solvent recyclability while maintaining RNA integrity further enables closed loop, low waste workflows applicable to complex biological samples.