Porous Hydrogel-Mediated One-Step Selection of Mannoprotein-Targeted Aptamers for Early Diagnosis of Invasive Saccharomyces cerevisiae Infections.

Invasive fungal infections, particularly those caused by Saccharomyces cerevisiae, have emerged as a significant public health threat. Accurate and timely recognition of S. cerevisiae is essential for effective diagnosis and treatment. This study introduces a micro- and nanoscale-enabled diagnostic strategy that integrates porous hydrogel-mediated one-step aptamer selection, nanostructured magnetic capture, and CRISPR-based assay for sensitive S. cerevisiae detection. First, a diffusion-binding screening method in porous PEG hydrogels was developed to select high affinity aptamers that can recognize the mannoprotein from S. cerevisiae cell walls. Then, the selected aptamers were conjugated to magnetic beads (MBs) and further enhanced by rolling circle amplification (RCA), forming high-density nanostructured complexes (Apt-RCA@MBs) capable of capturing fungal yeast cells with >90% efficiency. Finally, coupling this nanostructured capture interface with a one-pot isothermal CRISPR-RPA quantification (OICRQ) assay enabled rapid and sensitive detection of S. cerevisiae in complex clinical samples and food samples, including blood, urine, saliva, wine, and grape juice. This work demonstrates how rational hydrogel microenvironment design and nanostructure-assisted molecular recognition can enhance bioanalytical performance, providing a versatile platform for fungal pathogen detection with potential applications in clinical diagnostics and food safety.