Abstract: The present embodiments relate to the multi-scale engineering of silk biopolymer-interlayer sensors for co-monitoring of nutrients. By manipulating various nano- to meso-structural properties of such biosensors, obtained are sensors with programmable sensitivity and selectivity to salts, sugars, and oils/fats. Notably, this approach requires no specialized nanomaterials or delicate biomolecules. Programmable biosensors are further formatted for wireless readout, and characteristics of these passive, wireless nutrient monitors are studied in-vitro. It is anticipated that such sensors can be utilized in emerging dictary tools for applications across food tracking and human health. In addition, it is expected that such strategies in structural engineering of sensors can be adaptable to existing or emerging selective or partially-selective sensors.

Abstract: A sensor device includes an inner hydrogel layer, a first planar metallic structure adjacent to a first surface of the inner hydrogel layer, and a second planar metallic structure adjacent to a second surface of the inner hydrogel layer opposite to the first surface. A sensor device further includes an encasing layer at least partially enclosing at least one of the inner hydrogel layer, the first planar metallic structure, and the second planar metallic structure. A method for use of the sensor device includes receiving at least one environmental stimulus, modifying a capacitance of a hydrogel in response to the received environmental stimulus, and generating an electrical stimulus response based on the modified capacitance. The method further includes modifying the capacitance of the hydrogel by modifying a resonant frequency of the hydrogel.