Biporous silica nanostructure-induced nanovortex in a microfluidic channel for nucleic acid enrichment, isolation, and, PCR-free detection

Abstract Efficient pathogen enrichment and nucleic acid (NA) isolation are critical for accurate and sensitive diagnosis of infectious diseases, especially those with low pathogen levels. Our study introduces a biporous silica nanofilms-embedded sample preparation chip (BSNFs-chip) for pathogen and NA enrichment/isolation. The BSNFs-chip features unique biporous nanostructures comprising large and small pore layers. Computational simulations confirm that these nanostructures enhance the surface area and promote the formation of nanovortex, resulting in improved capture efficiency. Notably, the BSNFs-chip demonstrates a 100-fold lower limit of detection (LOD) compared to conventional methods used for NA detection. Clinical validations using patient samples corroborate the superior sensitivity of the BSNFs-chip when combined with the luminescence resonance energy transfer (LRET) assay. The enhanced sample preparation efficiency of the BSNFs-chip, along with the facile and straightforward synthesis of the biporous nanostructures, offers a promising solution for polymer chain reaction (PCR)-free detection of NAs.