A K⁺-sensitive photonic crystal hydrogel sensor for efficient visual monitoring of hyperkalemia/hypokalemia

Abstract

Potassium ions (K+) play crucial roles in many biological processes and abnormal K+ levels in the body is usually associated with physiological disorders or diseases and thus developing K+-sensitive sensors/devices...

Multi-stimuli responsive photonic hydrogel based on a novel photonic crystal template containing gold nanorods

“…1–3 Therefore, a series of PC materials with vivid structural colors have been fabricated, which have significant application value in sensors, 4–6 drug delivery, 7–9 actuators, 10–12 printing 13–15 and other fields. 16–18 A hydrogel is a stimulus-responsive material due to its elastic network that can shrink and swell, so it is usually combined with PC to fabricate stimulus-responsive photonic hydrogels, which realize a visual conversion to optical signals by changing structural colors in response to external stimuli, such as light, 19,20 organic compounds and solvents, 21–24 metal ions, 25,26 temperature, 27–29 and pH. 30–32 For example, Zhao et al 33 combined a polymeric hydrogel with an SiO 2 inverse opal structure to prepare an inverse opal hydrogel (IOH) sensor which can respond to pH, temperature and ultraviolet light.…”

Opal photonic crystal double‐network hydrogel for visual detection through structural color and fluorescent responsiveness

“…1,2 Especially, stimuli-responsive hydrogels (e.g., photonic crystal hydrogels [3][4][5] and fluorescent hydrogels [6][7][8] ) are widely used in the field of visual detection, such as sensors for glucose, 9 organic solvents and compounds, [10][11][12] metal ions. [13][14][15] Photonic crystal hydrogels combine the unique structural colors of photonic crystals with the stimuli-responsiveness of hydrogels, because hydrogels can memorize or immobilize the periodic structure of photonic crystals. The volume change of photonic crystal hydrogels can cause the lattice spacing of photonic crystals to change accordingly, which results in a change of structural color of photonic crystal hydrogels.…”