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Kanamycin (Kana) is widely used as a veterinary medicine and its abuse causes a serious threat to human health, raising the urgent demand for detection of residual Kana in animalderived food with high specificity and sensitivity. Here, we developed a photoelectrochemical (PEC) biosensor for rapid quantification of Kana, with lead sulfide quantum dots/titanium dioxide nanoparticles (PbS QDs/TiO 2 NPs) as a photosensitive composite, a Kana-specific DNA aptamer as a functional sensor, and ruthenium(III) hexaammine (Ru(NH 3 ) 6 3+ ) as a signal booster. To prepare the PEC aptasensor, TiO 2 NPs, PbS QDs, and polyethyleneimine (PEI) were respectively used to modify the indium tin oxide electrode, and then the amine-terminated aptamer probe was connected to the PEI via glutaraldehyde. Finally, Ru(NH 3 ) 6 3+ was attached on the surface of the aptamer to increase the photocurrent intensity. When Kana binds competitively with Ru(NH 3 ) 6 3+ to the aptamer immobilized on the surface of the aptasensor, Ru(NH 3 ) 6 3+ will be released from the aptamer, resulting in a decrease of the photocurrent signal. This PEC aptasensor exhibits a good linear relationship between the photocurrent shift and the logarithm of Kana concentration within the range of 1.0−300.0 nmol L −1 , and the detection limit is 0.161 nmol L −1 . Importantly, the PEC aptasensor presented good detection selectivity owing to specific interaction with Kana and was successfully implemented to quantify Kana in honey and milk, suggesting that the PEC aptasensor has the potential of rapid detection of residual Kana in animal-derived foods.

The formation of high-nuclear silver(I) clusters remains elusive and their potential applications are still underdeveloped. Herein, we report a unprecedented gigantic Ag148 ([Ag148S26Cl30(C≡CBut)60](SbF6)6) cluster co-templated by Cl- and S2-, which...

The controllable construction of pure inorganic polyoxometalate (POM)­zite materials with well-defined secondary building units (SBUs) is of great challenge. In this work, three distinct POM porous framework compounds 1–3 based on [MoVI 36O112(H2O)16]8–({Mo36}) SBUs with various active growth points and transition-metal Ag linkers, both as countercations and structure directors, were self-assembled from simple salts to ordered porous frameworks (compound 1 is a 3D framework with channels of 20.1 Å in diameter, while compound 2 and compound 3 are 2D frameworks with channels of 29.1 and 26.8 Å in diameter, respectively, and the channels of compound 3 are formed by the fourfold spiral winding of {Mo36} SBUs) by controlling the reaction conditions, providing valuable experience for synthetic chemists to obtain more interesting and functional materials. The {Mo36}-based POM porous framework compounds 1–3 exhibit cell type-specific, dose-dependent, and pH-sensitive anticancer behavior, with the lowest IC50 in A549 lung cancer cells. Further, the monomer precursors AgNO3 and Mo36 SBU, however, are less cytotoxic to A549 cells than compound Ag–{Mo36}, suggesting a synergistic action of hybrid materials. Mechanistic insights into the anticancer activity of compounds 1–3 show that they induce mitochondria-mediated apoptosis and necrosis in A549 cells. Thus, {Mo36}-based POM porous framework materials with silver ions could serve as promising anticancer agents for lung cancer therapy.

Saliva has emerged as a promising noninvasive biofluid for the diagnosis of oral and systemic diseases, including viral infections. During the coronavirus disease 2019 (COVID-19) pandemic, a growing number of studies focused on saliva-based detection of severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2). Taking advantage of the WoS core collection (WoSCC) and CiteSpace, we retrieved 1021 articles related to saliva-based detection of SARS-CoV-2 and conducted a comprehensive bibliometric analysis. We analyzed countries, institutions, authors, cited authors, and cited journals to summarize their contribution and influence and analyzed keywords to explore research hotspots and trends. From 2020 to 2021, research focused on viral transmission via saliva and verification of saliva as a reliable specimen, whereas from 2021 to the present, the focus of research has switched to saliva-based biosensors for SARS-CoV-2 detection. By far, saliva has been verified as a reliable specimen for SARS-CoV-2 detection, although a standardized procedure for saliva sampling and processing is needed. Studies on saliva-based detection of SARS-CoV-2 will promote the development of saliva-based diagnostics and biosensors for viral detection. Collectively, our findings could provide valuable information to help scientists perceive the basic knowledge landscapes on saliva-based detection of SARS-CoV-2, the past and current research hotspots, and future opportunities.