Optimized erucic acid-based extract as a natural probe for viscosity detection of liquid safety

As the main substate participating during the liquid metamorphism processes, the abnormal micro-environmental viscosity is closely associated with the occurrence and development of objective circumstance degradation. Thus, it is of great importance to establish the convenient detection method toward viscosity monitoring. This work is focused on extracting one kind of erucic acid-based molecular probe (EAd) for sensing viscosity fluctuations in liquids. The electron donor phenolic hydroxyl group and acceptor carboxyl have established in this molecular structure via a coincidental pathway. Twisted intramolecular charge transfer (TICT) was formed, and the rotatable conjugate structure was utilized as the recognition site. Due to the restriction of rotatable parts, higher emission fluorescent signal can be found in the high-viscosity micro-environment. And a large Stokes shift (83.3 nm in glycerol), narrower energy band, high selectivity (x = 0.56), adaptability, sensitivity, and good photo-stability, the applications of signal releasing in the complex liquid system can be achieved. Moreover, this natural probe EAd can identify the thickening efficiency in a non-invasively mode, in particular, viscosity fluctuations have been screened and spoiled samples can be distinguished by analyzing signal intensities. We hope that natural scaffold will provide a new reference toward liquid quality and safety inspection.