Rapid and sensitive detection of Epstein-Barr virus cell-free DNA (EBV cfDNA) is crucial for early diagnosis and monitoring of nasopharyngeal carcinoma (NPC), but accessibility to screening is limited by complicated and costly conventional DNA isolation and purification approaches. Here, a fully integrated ion concentration polarization (ICP)-enriched and nanozyme-catalyzed lateral flow assay (ICP-cLFA) is developed, enabling total analysis of EBV cfDNA in whole blood samples, with DNA isolation, pre-concentration, and amplification performed on a microfluidic chip, consequently providing the signal readout within 75 min. Specifically, ICP preconcentration and amplification steps, together with target recognition catalyzed by a platinum-decorated mesoporous gold nanosphere (MGNS@Pt) nanozyme, result in an ultralow detection limit of 4 aM in standard cfDNA samples and 100 aM in whole blood from NPC-bearing rats.
View Article and Find Full Text PDFConsidering the high risk of heavy metal ions (HMIs) transferring through the food chain and accumulating in milk, a flexible and facile point-of-care testing (POCT) platform is urgently needed for the accurate, sensitive, and highly selective on-site quantification of multiple HMIs in milk. In this work, a cost-effective disk with six screen-printed electrodes (SPEs) was designed for hand-held electrochemical detection. Metal organic frameworks (MOFs) were adopted to amplify and enhance the electrochemical signals of methylene blue (MB).
View Article and Find Full Text PDFExosomes are small extracellular vesicles that can be utilized as noninvasive biomarkers for diagnosis and treatment of cancer and other diseases. This study reports on a strategy involving a hybridized chain reaction-amplified chain coupled with an alkaline phosphatase-induced Ag-shell nanostructure for the ultrasensitive and rapid surface-enhanced Raman scattering immunoassay of exosomes. Exosomes from prostate cancer were captured using prostate-specific membrane antigen aptamer-modified magnetic beads; then, the hybridized chain reaction-amplified chain was released, incorporating a large number of functional moieties with signal amplification effects.
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