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A smart contact lens can be used as an excellent interface between the human body and an electronic device for wearable healthcare applications. Despite wide investigations of smart contact lenses for diagnostic applications, there has been no report on electrically controlled drug delivery in combination with real-time biometric analysis. Here, we developed smart contact lenses for both continuous glucose monitoring and treatment of diabetic retinopathy. The smart contact lens device, built on a biocompatible polymer, contains ultrathin, flexible electrical circuits and a microcontroller chip for real-time electrochemical biosensing, on-demand controlled drug delivery, wireless power management, and data communication. In diabetic rabbit models, we could measure tear glucose levels to be validated by the conventional invasive blood glucose tests and trigger drugs to be released from reservoirs for treating diabetic retinopathy. Together, we successfully demonstrated the feasibility of smart contact lenses for noninvasive and continuous diabetic diagnosis and diabetic retinopathy therapy.

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Machines have greatly contributed to the human civilization, enabling tasks beyond our capacities for improved quality of life. Recently, the progress in nanotechnology has triggered to build a miniaturized machine of nanoscale. In this context, synthetic nanomotors have gained considerable interest because of their great promise for diverse applications. Currently, the movement control of these nanomotors has been widely investigated using various stimuli. Here, we demonstrate near-infrared (NIR) light controlled on/off motion of stomatocyte nanomotors powered by the conversion of hydrogen peroxide. The nanomotors encapsulating naphthalocyanine (NC) are aggregated or separated (collective motion) with or without near-IR light illumination, resulting in the well-controlled movement. Remarkably, the nanomotors can move directionally toward hydrogen peroxide released from cancer cells and photothermally ablate the cancer cells. Taken together, our stomatocyte nanomotor systems can be effectively harnessed for autonomous photothermal cancer therapy.

Smart contact lenses for continuous glucose monitoring (CGM) have great potential for huge clinical impact. To date, their development has been limited by challenges in accurate detection of glucose without hysteresis for tear glucose monitoring to track the blood glucose levels. Here, long‐term robust CGM in diabetic rabbits is demonstrated by using bimetallic nanocatalysts immobilized in nanoporous hydrogels in smart contact lenses. After redox reaction of glucose oxidase, the nanocatalysts facilitate rapid decomposition of hydrogen peroxide and nanoparticle‐mediated charge transfer with drastically improved diffusion via rapid swelling of nanoporous hydrogels. The ocular glucose sensors result in high sensitivity, fast response time, low detection limit, low hysteresis, and rapid sensor warming‐up time. In diabetic rabbits, smart contact lens can detect tear glucose levels consistent with blood glucose levels measured by a glucometer and a CGM device, reflecting rapid concentration changes without hysteresis. The CGM in a human demonstrates the feasibility of smart contact lenses for further clinical applications.

Obesity is associated with the risk of developing several severe diseases, such as metabolic disorder, diabetes, and heart diseases. Despite wide investigation and trials, a noninvasive obesity therapy is still an important medical unmet need, targeting the abnormal adipose tissue. Here, we developed hyaluronate–hollow gold nanosphere–adipocyte-targeting peptide (HA–HAuNS–ATP) conjugates for the photothermal ablation of adipose tissues. The HA–HAuNS–ATP conjugate could be noninvasively delivered into the skin and effectively target to adipocytes in the subcutaneous. With near-infrared laser illumination, HA–HAuNS–ATP conjugate enabled highly effective photothermal ablation of adipose tissues in C57BL/6 obesity mice. The photoacoustic imaging confirmed the successful transdermal delivery and the photothermal lipolysis of HA–HAuNS–ATP conjugate. Taken together, the transdermal HA–HAuNS–ATP conjugate might have a great potential for noninvasive photothermal lipolysis.

Diabetic retinopathy is currently treated by highly invasive repeated therapeutic injections and surgical interventions without complete vision recovery. Here, a noninvasive smart wireless far red/near‐infrared (NIR) light emitting contact lens developed successfully for the repeated treatment of diabetic retinopathy with significantly improved compliance. A far red/NIR light emitting diode (LED) is connected with an application‐specific integrated circuit chip, wireless power, and communication systems on a PET film, which is embedded in a silicone elastomer contact lens by thermal crosslinking. After in vitro characterization, it is confirmed that the retinal vascular hyper‐permeability induced by diabetic retinopathy in rabbits is reduced to a statistically significant level by simply repeated wearing of smart far red/NIR LED contact lens for 8 weeks with 120 µW light irradiation for 15 min thrice a week. Histological analysis exhibits the safety and feasibility of LED contact lenses for treating diabetic retinopathy. This platform technology for smart LED contact lens would be harnessed for various biomedical photonic applications.

Noninvasive real-time biosensors to measure glucose levels in the body fluids have been widely investigated for continuous glucose monitoring of diabetic patients. However, they suffered from low sensitivity and reproducibility due to the instability of nanomaterials used for glucose biosensors. Here, we developed a hyaluronate−gold nanoparticle/glucose oxidase (HA− AuNP/GOx) complex and an ultralow-power application-specific integrated circuit chip for noninvasive and robust wireless patchtype glucose sensors. The HA−AuNP/GOx complex was prepared by the facile conjugation of thiolated HA to AuNPs and the following physical binding of GOx. The wireless glucose sensor exhibited slow water evaporation (0.11 μL/min), fast response (5 s), high sensitivity (12.37 μA•dL/mg•cm 2 ) and selectivity, a low detection limit (0.5 mg/dL), and highly stable enzymatic activity (∼14 days). We successfully demonstrated the strong correlation between glucose concentrations measured by a commercially available blood glucometer and the wireless patch-type glucose sensor. Taken together, we could confirm the feasibility of the wireless patch-type robust glucose sensor for noninvasive and continuous diabetic diagnosis.