Glucose‐Sensing Photonic Nanochain Probes with Color Change in Seconds

Abstract

Glucose‐sensing photonic crystals are promising for the significant advance of continuous glucose monitoring systems due to the naked‐eye colorimetric readouts and noninvasive detection of diabetes, but the long response time hampers their practical applications. Here, for the first time probes of photonic nanochains (PNCs) are demonstrated that are capable of continuously and reversibly sensing glucose concentration ([glucose]) variation within seconds by color change without power consumption, much faster by 2–3 orders of magnitude than previous ones. They are comprised of 1D equidistant arrays of magnetic nanoparticles enveloped by tens‐of‐nanometer‐thick phenylboronic acid‐functionalized hydrogels, and fabricated by developing selective concentration polymerization of monomers in binary microheterogeneous solvents of dimethyl sulfoxide (DMSO) and H2O. In this process, both 3‐acrylamido phenylboronic acid (AAPBA) and N‐2‐hydroxyethyl acrylamide (HEAAm) are preferentially dissolved in the small volume of free DMSO concentrated in the vicinity of poly vinylpyrrolidone coated Fe3O4 colloidal nanoparticles (Fe3O4@PVP), yielding Fe3O4@PVP@poly(AAPBA‐co‐HEAAm) PNCs after UV irradiation under magnetic field. The PNCs in phosphate buffered solution have a wavelength‐shift range up to 130 nm when [glucose] changes from 0 to 20 × 10−3 m. The results can facilitate real‐time glucose monitoring and provide an alternative to produce functional organic–inorganic nanostructures.

Bio-inspired color-changing and self-healing hybrid hydrogels for wearable sensors and adaptive camouflage

“…[25][26][27][28] Wearable sensors that are formed based on the freely designed polymeric structures of the conductive polymers are highly desirable compared with conventional wearable sensors that are not resistant to stretching. [29][30][31][32][33] To solve the problems regarding the widespread and sustainable application of wearable sensors, self-healing hydrogels with excellent ionic conductivity are an irreplaceable candidate. [34][35][36][37][38] Flexible hydrogels exhibiting high ionic conductivity are one of the irreplaceable candidates for wearable sensing materials, as compared with conventional wearable sensing materials that are not tensile resistant.…”

Toward High Sensitivity: Perspective on Colorimetric Photonic Crystal Sensors

“…The advances in newly developed synthetic polymers − and natural products (e.g., cellulose, − chitin nanocrystals, and proteins , ) as structural color materials offer colorimetric PC sensors with facilely tunable responsiveness and extending properties (e.g., self-healing , and adhesive , properties). On the other hand, the fabrication strategies of PCs such as magnetic assembly, − polymers assembly by solvent treatment, , microfluidics, spray coating, printing, − etc., provide opportunities for preparing sensors with diverse materials and structures as well as low-cost and large-scale manufacturing. Colorimetric PC sensors have been further applied for multidisciplinary investigations, such as microneedle patches, organ-on-a-chip and tissue engineering, − soft actuators and robots, , solar cells, smart windows, etc., and will significantly facilitate the development of various devices with self-reporting properties.…”

High-Precision Colorimetric Sensing by Dynamic Tracking of Solvent Diffusion in Hollow-Sphere Photonic Crystals

“…Materials based on photonic crystals (PCs) are highly attractive for this purpose because their optical properties are determined by their nanoscale periodic arrangement and dielectric environment, which change in response to many physical and chemical external stimuli. In addition to sensing [ 1 – 8 ], they are also useful for a broad range of applications, including printing [ 9 – 13 ], anticounterfeiting [ 14 – 16 ], display units [ 17 – 20 ], photocatalysis [ 21 – 23 ], and solar energy harvesting [ 24 , 25 ]. In particular, they have been extensively explored as active components in sensors by offering simple optical and visual means to determine physicochemical parameters of various analytes [ 26 , 27 ].…”