Colorimetric Photonic Tongue for Metal Ions Screening

Abstract

Metal ions screening in body fluid is vital for human health monitoring. Here, inspired by the physiological taste sensing functions of tongue, we reported novel colorimetric photonic tongue for multiple metal ions screening by using spherical structural color hydrogel particles (SCHPs) as sensory units. As the SCHPs were with acrylic acid (AA)-based skeleton, the sensory units could respond by showing color variation to metal ions unspecifically, in a way similar with the receptors in the taste buds. Thus, through analyzing the sensory information of all units, a colorimetric “fingerprint” for each metal ion could be obtained and stored in a database. Based on this, we have constructed a portable, reusable and biocompatible device by integrating the SCHP arrays into a test strip microchip for real-time metal ions monitoring, through which the target ions could be distinguished by multivariate data analysis for pattern recognition. These features indicated that the proposed photonic tongue is valuable for screening metal ions of biological samples in clinical diseases diagnosis.

Keywords: bio-inspired, colorimetric tongue, structural color, ion sensor, microfluidics