With the rise in public health awareness and the increasing demand for environmental protection, the biotoxicity assessment of chemical substances has become a multidisciplinary research hotspot and has necessitated the development of multiresponsive, user-friendly sensing materials and methods for the identification of various analytes. This study formulated a novel sensing strategy based on the Hofmeister effect, which modulated the network structure and multimodal physicochemical properties of cellulose nanofiber/gelatin hydrogels through ion-specific interactions. A multiparameter responsive sensitivity coefficient (CPR) analysis model was also developed. This model enabled the qualitative and quantitative analysis of various anions and cations by evaluating the electrical, mechanical, and physical responses of the hydrogel, thereby overcoming the limitations of single-parameter sensing. Experimental results demonstrated that the compressive strength of the hydrogel increased 3.92-fold through the salting-out effect of Na 2 SO 4 , yielding an electrical conductivity of up to 2.89 S/m in a composite ion environment. More importantly, by combining the CPR model with linear discriminant analysis, high-precision identification of nine single ions and six composite ions was successfully achieved. In simulated sweat detection, the sensor achieved a 100% identification accuracy for three physiological states: healthy, dehydrated, and postexercise. This technology is applicable to various fields, including environmental monitoring, medical and health services, and sports management optimization.
Chen et al. (Thu,) studied this question.