Room temperature synthesis of nanocomposite thin films with embedded Cs2AgIn0.9Bi0.1Cl6 lead-free double perovskite nanocrystals with long-term water stability, wide range pH tolerance, and high quantum yield.

The synthesis of Cs2AgIn0.9Bi0.1Cl6 nanocrystals was achieved at room temperature under ambient conditions using the ligand-assisted reprecipitation (LARP) method. The synthesized NCs exhibit bright orange emission when excited at 375 nm and have broad photoluminescence (PL) emission spectra with a maximum of 630 nm. A photoluminescence quantum yield (PLQY) of 36% was observed in these NCs without any polymer coatings. Polystyrene (PS), and poly (methyl methacrylate) (PMMA) were used to enhance the water stability and PLQY values up to 64%. Nanocomposite thin films with these polymer encapsulations exhibit good thermal stability up to at least 353 K and high quantum yields. PMMA-coated NCs showed long-term water stability for at least 4 months. The composites remain photostable when in contact with water for at least 120 min under continuous 365 nm UV illumination at 1 mW cm-2. Due to their excellent optical properties, aqueous stability, and wide range pH tolerance, these nanocomposite thin films could be employed for a variety of biological applications.

Combustion-Derived Pollutants Linked with Kidney Disease in Low-Lying Flood-Affected Areas in the Balkans.

Tens of thousands of people in southern Europe suffer from Balkan endemic nephropathy (BEN), and four times as many are at risk. Incidental ingestion of aristolochic acids (AAs), stemming from the ubiquitousAristolochia clematitis(birthwort) weed in the region, leads to DNA adduct-induced toxicity in kidney cells, the primary cause of BEN. Numerous cofactors, including toxic organics and metals, have been investigated, but all have shown small contributions to the overall BEN relative to non-BEN village distribution gradients. Here, we reveal that combustion-derived pollutants from wood and coal burning in Serbia also contaminate arable soil and test as plausible causative factors of BEN. Using a GC-MS screening method, biomass-burning-derived furfural and coal-burning-derived medium-chain alkanes were detected in soil samples from BEN endemic areas levels at up to 63-times and 14-times higher, respectively, than in nonendemic areas. Significantly higher amounts were also detected in colocated wheat grains. Coexposure studies with cultured kidney cells showed that these pollutants enhance DNA adduct formation by AA, - the cause of AA nephrotoxicity and carcinogenicity. With the coincidence of birthwort-derived AAs and the widespread practice of biomass and coal burning for household cooking and heating purposes and agricultural burning in rural low-lying flood-affected areas in the Balkans, these results implicate combustion-derived pollutants in promoting the development of BEN.

Effects of Heavy Metal Co-Exposure on the formation of DNA Adducts from Aristolochic Acid I: Implications for Balkan Endemic Nephropathy Development.

Accumulated evidence has shown that Balkan endemic nephropathy (BEN) is a multifactorial environmental disease, with exposure to aristolochic acids (AA), and the associated DNA adduct formation, as a key causative factor of BEN development. Here, we show that coexposure to arsenic, cadmium, and iron increases the DNA adduct formation of AA in cultured kidney cells, while exhibiting both an exposure concentration and duration dependence. In contrast, coexposure to calcium and copper showed a decreasing DNA adduct formation. Because DNA damage is responsible for both the nephrotoxicity and carcinogenicity of AA, these results shed greater light on the endemic nature of BEN.