The outbreak of SARS-CoV-2 is posing serious global public health problems. Facing the emergence of this pandemic, we established a portable microfluidic immunoassay system for easy-to-use, sensitive, rapid (<15 min), multiple, and on-site detection of IgG/IgM/Antigen of SARS-CoV-2 simultaneously. This integrated method was successfully applied for detecting SARS-CoV-2 IgM and IgG antibodies in clinical human serum as well as SARS-CoV-2 antigen in pharyngeal swabs from 26 patients with COVID-19 infection and 28 uninfected people. The assay demonstrated high sensitivity and specificity, which is promising for the diagnosis and monitoring as well as control of SARS-CoV-2 worldwide.

Due to ultra-high reactivity, direct determination of free radicals, especially hydroxyl radical (•OH) with ultra-short lifetime, by field-effect transistor (FET) sensors remains a challenge, which hampers evaluating the role that free radical plays in physiological and pathological processes. Here, we develop a •OH FET sensor with a graphene channel functionalized by metal ion indicators. At the electrolyte/graphene interface, highly reactive •OH cuts the cysteamine to release the metal ions, resulting in surface charge de-doping and a current response. By this inner-cutting strategy, the •OH is selectively detected with a concentration down to 10 −9 M. Quantitative metal ion doping enables modulation of the device sensitivity and a quasi-quantitative detection of •OH generated in aqueous solution or from living cells. Owing to its high sensitivity, selectivity, real-time label-free response, capability for quasi-quantitative detection and user-friendly portable feature, it is valuable in biological research, human health, environmental monitoring, etc.

Exosomes, known as nanometer‐sized vesicles (30–200 nm), are secreted by many types of cells. Cancer‐derived exosomes have great potential to be biomarkers for early clinical diagnosis and evaluation of cancer therapeutic efficacy. Conventional detection methods are limited to low sensitivity and reproducibility. There are hundreds of papers published with different detection methods in recent years to address these challenges. Therefore, in this review, pioneering researches about various detection strategies are comprehensively summarized and the analytical performance of these tests is evaluated. Furthermore, the exosome molecular composition (protein and nucleic acid) profiling, a single exosome profiling, and their application in clinical cancer diagnosis are reviewed. Finally, the principles and applications of machine learning method in exosomes researches are presented.

As eries of calix [4]pyrrole-based crosslinked polymer networks designed for iodine capture is reported. These materials were prepared by Sonogashira coupling of a,a,a,atetra(4-alkynylphenyl)calix [4]pyrrole with bishalide building blocks with different electronic properties and molecular sizes. Despite their low Brunauer-Emmett-Teller surface areas, iodine vapor adsorption capacities of up to 3.38 gg À1 were seen, af inding ascribed to the presence of al arge number of effective sorption sites including macrocyclic p-rich cavities, aryl units,a nd alkyne groups within the material. One particular system, C[4]P-BTP,was found to be highly effective at iodine capture from water (uptake capacity of 3.24 gg À1 from ac oncentrated aqueous KI/I 2 solution at ambient temperature). Fast capture kinetics (k obs = 7.814 gg À1 min À1 ) were seen. Flow-through adsorption experiments revealed that C[4]P-BTP is able to remove 93.2 %o fi odine from an aqueous source phase at aflow rate of 1mLmin À1 .

Polymer dots (Pdots) have become attractive electrochemiluminescence (ECL) luminophores due to their facile synthesis, easy modification, and stable electrochemical and optical properties. However, their ECL efficiency is not high enough for practical applications. In this work, we proposed an ECL immunosensor based on localized surface plasmon resonance (LSPR) between AuNPs and Pdots for the determination of pancreatic cancer exosomes. Based on the finite-difference time-domain simulations and the band energy of Pdots and AuNPs, we proposed the possible LSPR mechanism. The hot electrons of plasmonic AuNPs were photoexcited to surface plasmon states by ECL emission of Pdots, and then the excited hot electrons were transferred to the conduction band of Pdots, which significantly improved the ECL efficiency of Pdots. The ECL immunosensor displayed a wide calibration range of 1.0 × 10 3 to 1.0 × 10 6 particles/mL with a detection limit of 400 particles/mL. Cancer-related protein profiling revealed high selectivity toward different expressions of exosomal surface proteins from PANC-01, HeLa, MCF-7, and HPDE6-C7 cell lines. The proposed ECL system exhibits a promising prospect for protein biomarker profiling and early cancerrelated diagnosis.

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Cancer-cell-derived exosomes are regarded as noninvasive biomarkers for early cancer diagnosis because of their critical roles in intercellular communication and molecular exchange. A robust aptamer-initiated catalytic hairpin assembly (AICHA) fluorescence assay is proposed for universal, sensitive detection of cancer-derived exosomes. The AICHA was verified with the specific detection of MCF-7 cell-derived exosomes with a wide calibration range of 8.4 particles/μL to 8.4 × 105 particles/μL and a low detection limit (LOD) of 0.5 particles/μL. The universality of the AICHA method was verified for PANC-1 cell-derived exosomes, the LOD of which was determined to be 0.1 particles/μL. The performances in serum samples were detected with a recovery rate range of 95.45–106.2%, which demonstrates its significant potential for protein biomarker analysis and cancer diagnosis.

As eries of calix [4]pyrrole-based crosslinked polymer networks designed for iodine capture is reported. These materials were prepared by Sonogashira coupling of a,a,a,atetra(4-alkynylphenyl)calix [4]pyrrole with bishalide building blocks with different electronic properties and molecular sizes. Despite their low Brunauer-Emmett-Teller surface areas, iodine vapor adsorption capacities of up to 3.38 gg À1 were seen, af inding ascribed to the presence of al arge number of effective sorption sites including macrocyclic p-rich cavities, aryl units,a nd alkyne groups within the material. One particular system, C[4]P-BTP,was found to be highly effective at iodine capture from water (uptake capacity of 3.24 gg À1 from ac oncentrated aqueous KI/I 2 solution at ambient temperature). Fast capture kinetics (k obs = 7.814 gg À1 min À1 ) were seen. Flow-through adsorption experiments revealed that C[4]P-BTP is able to remove 93.2 %o fi odine from an aqueous source phase at aflow rate of 1mLmin À1 .