Proteins orchestrate nearly all cellular processes and serve as key biomarkers and therapeutic targets. Conventional detection bioassays are confined in centralized laboratories, dependent on bulky instruments or labeling workflows. Currently, they are limited to merely read out the concentration of proteins, leaving molecular details such as layer thickness and orientation inaccessible, which are critical for functional assessment. Here, we present a Mie-resonant nanosensor that transduces biomolecular binding events into vivid colorimetric changes through high-order quadrupole modes in the visible spectrum, unprecedently extending colorimetric sensing to the biomolecular scale. Coherent quadrupole interference enhances backward scattering enabling optical readout of protein layers as thin as 1.8 nm along with recognizing protein orientation, termed as the visualized Mie-resonance sensing (VIMS). Both quality control of antibody functionalization and quantitative detection of antigens can be achieved via VIMS, demonstrating a 0.4 pg/mL detection limit of cardiac troponin T (cTnT) within 20 minutes. Integrated with a smartphone-compatible point-of-care platform, the assay reliably diagnoses acute myocardial infarction (AUC > 0.95) from serum, saliva and urine (N=220), and identifies elevated baseline cTnT in high-stress populations. This work bridges nanophotonic field confinement with biomolecular structural resolution, enabling label-free, portable, and quantitative molecular-scale optical sensing for decentralized precision diagnostics.

Tacrolimus (FK506) is a potent immunosuppressant widely used to prevent rejection following organ transplantation. In this study, we employed a photonic crystal microarray-based competitive assay to measure tacrolimus blood concentrations, facilitating bedside and at-home monitoring for transplant recipients. The photonic crystal microarray technology offers flexibility, cost-effectiveness, and high efficiency. When integrated with a portable fluorescence intensity detector, it enables rapid and quantitative analysis. By fabricating the photonic crystal microarray and leveraging the photonic crystal bandgap enhancement effect to amplify the fluorescence intensity of probe molecules, the detection sensitivity is significantly improved. The photonic crystal microarray demonstrated a remarkable fluorescence enhancement factor of 17.2-fold compared to conventional substrates, significantly improving the sensitivity of tacrolimus detection. The optimized system achieved a detection limit of 0.4 ng·mL⁻¹, enabling rapid and accurate quantification of tacrolimus concentration within 20 min.

The development of three-dimensional (3D) space light angle detection is vital in optical technology for applications such as 3D imaging, computer vision, and augmented reality. Current methods involve advanced sensors and algorithms, including time-of-flight cameras, which need multiple cameras and light sources to improve accuracy. However, it is a great challenge to integrate these complex components into compact devices. Subwavelength semiconductor structures offer optical resonance characteristics, enabling precise light–matter interaction regulation. A 3D star-like photodetector, fabricated using a template assistant printing strategy, demonstrates optical resonances of the subwavelength facade and the shielding effect of spatial arrangement. It achieves light angle detection with the resolution of 10° in vertical space and the resolution of 36° in horizontal space, making it a promising prototype for various applications.

Reaction kinetics of nanoparticles can be controlled by tuning the Peclet number (Pe) as it is an essential parameter in synthesis of multi-sized nanoparticles. Herein, we propose to implement a self-driven multi-dimension microchannels reactor (MMR) for the one droplet synthesis of multi-sized nanoparticles. By carefully controlling the Pe at the gas–liquid interface, the newly formed seed crystals selectively accumulate and grow to a specific size. By the combination of microchannels of different widths and lengths, one droplet reaction in the same apparatus achieves the synchronous synthesis of diverse nanoparticles. MMR enables precise control of nanoparticle diameter at 5 nm precision in the range of 10–110 nm. The use of MMR can be extended to the synthesis of uniform Ag, Au, Pt, and Pd nanoparticles, opening towards the production and engineering of nanostructured materials. This approach gives the chance to regulate the accumulation probability for precise synthesis of nanoparticles with different diameters.