Despite the potential indicating role of tyrosinase (TYR) in cutaneous melanoma, how to capture the real changes of TYR in suspicious skin remains a major challenge. Unlike the traditional human serum test, this study reports a sensing platform that incorporates a wearable microneedle (MN) patch and trimetallic Au@Ag-Pt nanoparticles (NPs) for surface-enhanced Raman scattering (SERS) and colorimetric dual-mode detecting TYR in human skin toward potential melanoma screening. In the presence of TYR, catechol immobilized on MN is preferentially oxidized to benzoquinone, which competitively impedes the interaction of MN and Au@Ag-Pt NPs, triggering the SERS-colorimetric signal reciprocal switch.
View Article and Find Full Text PDFA new lateral flow immunoassay strip (LFIA) combining sensitive detection and identification of multiple bacteria remains a huge challenge. In this study, we first developed multifunctional urchin-shaped Au-Ag@Pt nanoparticles (UAA@P NPs) with a unique combination of colorimetric-SERS-photothermal-catalytic (CM/SERS/PT/CL) properties and integrated them with LFIA for multiplexed detection and specific discrimination of pathogenic bacteria in blood samples. Unlike the conventional LFIA that relied on antibody (Ab), this novel LFIA introduced 4-mercaptophenylboronic acid (4-MPBA) as an ideal Ab replacer that was functionalized on UAA@P NPs (UAA@P/M NPs) with outstanding binding and enrichment capacities toward bacteria.
View Article and Find Full Text PDFUltra-sensitive detection of cancer-related biomarkers in serum is of great significance for early diagnosis, treatment, prognosis, and staging of cancer. In this work, we proposed a surface-enhanced Raman scattering and fluorescence (SERS/FL) dual-mode biosensor for hepatocellular carcinoma (HCC)-related miRNA (miR-224) detection using the composition of well-arranged Au nanoarrays (Au NAs) substrate coupled with the target-catalyzed hairpin assembly (CHA) strategy. The hot spots densely and uniformly distributed on the Au array offers considerably enhanced and reproducible SERS signals, along with their wide and open surface to facilitate miR-224 adsorption.
View Article and Find Full Text PDFUltra-sensitive detection of pathogenic bacteria is of great significance in the early stage of bacterial infections and treatment. In this work, we report a novel strategy using multifunctional Au nano-bridged nanogap nanoparticles (Au NNPs)-based sandwich nanocomposites, that made of Concanavalin A-conjugated FeO@SiO NPs (ConA-FeO@SiO NPs)/bacteria/aptamer-modified Au NNPs (apt-Au NNPs), for bacteria discrimination and quantitative detection by surface-enhanced Raman scattering (SERS) and inductively coupled plasma mass spectrometry (ICP-MS), and subsequently photothermal antibacterial assay. The sandwich nanocomposite consists of ConA-FeO@SiO NPs to magnetically enrich and photothermal killing bacteria, and dual-signal tags of apt-Au NNPs for both SERS sensing and ICP-MS quantification.
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