Tie Li

Intraocular pressure (IOP) is amenable to direct regulation and a critical indicator for numerous ocular disorders. Continuous, long-term IOP monitoring provides indispensable clinical data, supporting early diagnosis, risk stratification, and personalized treatment. This review comprehensively summarizes the working principles, key performance metrics, and clinical progress of wearable and implantable IOP sensors. The text elucidates the structural integration of wireless power supplies, signal transmission, and artificial intelligence within wireless IOP monitoring systems. Furthermore, manufacturing and optimization strategies are highlighted, and the considerable advantages of nanomaterials and micro/nanostructures are comprehensively summarized, emphasizing their crucial role in current IOP monitoring devices. Additionally, the diverse applications of IOP sensors in disease diagnosis and therapeutic management are discussed, underscoring their potential for personalized and precision medicine, alongside the challenges remaining in their clinical translation. Finally, current bottlenecks and limitations are addressed, outlining potential solutions, future trends, and potential breakthroughs in next-generation IOP monitoring.

Silicon (Si)-based or even silicon carbide (SiC)-based heat flux sensors often experience material degradation or structural failure due to stress at temperatures above 1200 °C. This paper presents the design and fabrication of an advanced transient high-temperature heat flux sensor, by micromachining an air cylindrical thermal insulation-chamber from a sandwich-structure of silicon carbide-on-insulator (SiCOI) over the silicon substrate. The temperature of the sensor at high heat flux is significantly reduced by utilizing the thermal conductivity of SiCOI material, which is much better than that of SOI material. The proposed structure significantly reduces stress under high-temperature conditions, enabling reliable operation in extreme environments. The sensor is mounted on a ceramic baseplate instead of transistor outline (TO) packaging for high-temperature testing and exhibits exceptional performance over conventional designs, achieving a maximum operating temperature of 1400 °C and stable operation under a heat flux of 3.45 MW/m² without the need for water cooling. It offers a rapid response time of 0.9 ms and high sensitivity of 42 μV·m²/kW. These remarkable features make it a highly competitive solution for detecting heat flux in high-temperature environments.

Expiratory CO₂ concentrations can directly reflect human physiological conditions, and their detection is highly important in the treatment and rehabilitation of critically ill patients. Existing respiratory gas analyzers suffer from large sizes and high power consumption due to the limitations of the internal CO₂ sensors, which prevent them from being wearable to track active people. The internal and external interference and sensitivity limitations must be overcome to realize wearable respiratory monitoring applications for CO₂ sensors. In this work, an ultra-compact CO₂ sensor was developed by integrating a microelectromechanical system emitter and thermopile detectors with an optical gas chamber; the power consumption of the light source and ambient temperature of the thermally sensitive devices were reduced by heat transfer control; the time to reach stabilization of the sensor was shortened; the humidity resistance of the sensor was improved by a dual-channel design; the light loss of the sensor was compensated by improving the optical coupling efficiency, which was combined with the amplitude trimming network to equivalently improve the sensitivity of the sensor. The minimum size of the developed sensor was 12 mm × 6 mm × 4 mm, and the reading error was 2 sensor developed using this strategy has great potential for wearable respiratory monitoring applications.

The silicon nanowire field-effect transistor (SiNW FET) has been developed for over two decades as an ultrasensitive, label-free biosensor for biodetection. However, inconsistencies in manufacturing and surface functionalization at the nanoscale have led to poor sensor-to-sensor consistency in performance. Despite extensive efforts to address this issue through process improvements and calibration methods, the outcomes have not been satisfactory. Herein, based on the strong correlation between the saturation response of SiNW FET biosensors and both their feature size and surface functionalization, we propose a calibration strategy that combines the sensing principles of SiNW FET with the Langmuir-Freundlich model. By normalizing the response of the SiNW FET biosensors (ΔI/I₀) with their saturation response (ΔI/I₀)_max, this strategy fundamentally overcomes the issues mentioned above. It has enabled label-free detection of nucleic acids, proteins, and exosomes within 5 min, achieving detection limits as low as attomoles and demonstrating a significant reduction in the coefficient of variation. Notably, the nucleic acid test results exhibit a strong correlation with the ultraviolet-visible (UV-vis) spectrophotometer measurements, with a correlation coefficient reaching 0.933. The proposed saturation response calibration strategy exhibits good universality and practicability in biological detection applications, providing theoretical and experimental support for the transition of mass-manufactured nanosensors from theoretical research to practical application.

We employed RbI additive, constructed heterojunction, and used TOPO post-treatment for suppressing non-radiative recombination of MA-free WBG perovskite. The device showed a record PCE of 23.35%, a high V _OC of 1.3 V and the impressive stability.

Dementia is a brain disease which results in irreversible and progressive loss of cognition and motor activity. Despite global efforts, there is no simple and reliable diagnosis or treatment option. Current diagnosis involves indirect testing of commonly inaccessible biofluids and low-resolution brain imaging. We have developed a portable, wireless readout-based Graphene field-effect transistor (GFET) biosensor platform that can detect viruses, proteins, and small molecules with single-molecule sensitivity and specificity. We report the detection of three important amyloids, namely, Amyloid beta (Aβ), Tau (τ), and α-Synuclein (αS) using DNA aptamer nanoprobes. These amyloids were isolated, purified, and characterized from the autopsied brain tissues of Alzheimer’s Disease (AD) and Parkinson’s Disease (PD) patients. The limit of detection (LoD) of the sensor is 10 fM, 1–10 pM, 10–100 fM for Aβ, τ, and αS, respectively. Synthetic as well as autopsied brain-derived amyloids showed a statistically significant sensor response with respect to derived thresholds, confirming the ability to define diseased vs. nondiseased states. The detection of each amyloid was specific to their aptamers; Aβ, τ, and αS peptides when tested, respectively, with aptamers nonspecific to them showed statistically insignificant cross-reactivity. Thus, the aptamer-based GFET biosensor has high sensitivity and precision across a range of epidemiologically significant AD and PD variants. This portable diagnostic system would allow at-home and POC testing for neurodegenerative diseases globally.