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Submitted by Vivian Rosa Storti (vivian.storti@unesp.br) on 2019-08-23T15:03:10Z No. of bitstreams: 1 fraceto_lf_preprint_soro_ecodesignedpaper.pdf: 1703375 bytes, checksum: 0750647a29c04919959a376041b2d4d3 (MD5) Approved for entry into archive by Luana Priscila Costa (luana@reitoria.unesp.br) on 2019-08-23T17:53:29Z (GMT) No. of bitstreams: 1 fraceto_lf_preprint_soro_ecodesignedpaper.pdf: 1703375 bytes, checksum: 0750647a29c04919959a376041b2d4d3 (MD5) Made available in DSpace on 2019-08-23T17:53:29Z (GMT). No. of bitstreams: 1 fraceto_lf_preprint_soro_ecodesignedpaper.pdf: 1703375 bytes, checksum: 0750647a29c04919959a376041b2d4d3 (MD5) Previous issue date: 2019-07 Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) In this study we reported the development of a paper-based algal biosensor for the optical detection of nanoencapsulated-atrazine, a forefront nanoformulated herbicide with a high effective postemergence herbicidal activity. In particular, the unicellular green photosynthetic algae Chlamydomonas reinhardtii was immobilised on a paper substrate soaked with an agar thin film and placed in a glass optical measurement cell, obtaining a totally environmental-friendly device. Nanoencapsulated-atrazine was detected by following the variable fluorescence (1-VJ) parameter, which decreased inversely proportional to the herbicide concentrations, in a range between 0.5 and 200 nM, indicating a linear relationship in the measured dose-response curves and a detection limit of 4 pM. Interference studies resulted in a very slight interference in presence of 0.5 ppm copper and 10 ppb arsenic at safety limits, as well as a slight matrix effect and a satisfactory recovery value of 96 ± 5 % for 75 nM nanoencapsulated-atrazine in tap water. Stability studies were also performed obtaining a good storage stability up to 3 weeks. Results demonstrated the suitability of the proposed paper-based optical biosensor as a valid support in smart agriculture for on site, environmentally friendly, cost effective and sensitive nanoencapsulated-atrazine analysis Preprint Institute of Crystallography, National Research Council, Department of Chemical Sciences and Materials Technologies Department of Chemical Science and Technologies, Università di Roma Tor Vergata São Paulo State University (UNESP), Institute of Science and Technology of Sorocaba, Laboratory of Environmental Nanotechnology FAPESP: 2017/21004-5

Dichloromethane extracts of four diverse hazardous wastes (coke plant, herbicide manufacturing, pulp and paper, and oil refining) were evaluated for mutagenicity in strains TA98 and TA100 of Salmonella. These extracts also were tested for biological activity in short-term mammalian cell assays, including mutagenicity in L5178Y/TK +/- mouse lymphoma cells, chromosomal aberrations and sister chromatid exchanges in Chinese hamster ovary (CHO) cells, morphological transformation in BALB/c-3T3 cells, and teratogenic potential in mouse limb bud cells. The mammalian cell assays were performed using limited protocols that consisted of a preliminary testing of the extracts for cytotoxicity in CHO cells in order to estimate the appropriate dose range for the other assays. These assays were then performed once with only a few doses of extract; all but the mouse limb bud assay were performed in the presence of metabolic activation. Although all four of the wastes were presumptively positive for either mutation or cytogenetic effects, none of the wastes transformed BALB/c-3T3 cells. Further studies are needed to establish which mammalian cell assays, if any, might be useful complements to the Salmonella assay for the purpose of screening hazardous wastes.