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Biosensors & Bioelectronics Jan 2012The reactivity of photodegradation products of benzo(a)pyrene vs. DNA has been assessed using both genomic and oligonucleotide based DNA electrochemical sensors. The...
The reactivity of photodegradation products of benzo(a)pyrene vs. DNA has been assessed using both genomic and oligonucleotide based DNA electrochemical sensors. The kinetic of a photooxidation reaction of benzo(a)pyrene (BaP) carried out in controlled conditions using a 6 W UV lamp peaked at 365 nm has been studied using LC with fluorimetric detection. Degradation of benzo(a)pyrene by both UV and UV/H(2)O(2) exhibited pseudo-first-order reaction kinetics with half-lives ranging from 3.0 to 9.8h depending on the pH and on the amount of H(2)O(2). The oxidation products of benzo(a)pyrene obtained in different conditions were tested on genomic ssDNA electrochemical sensors obtained via immobilisation of salmon testis ss-DNA on graphite screen-printed electrodes. Guanines oxidation signals obtained using chronopotentiometry were used to detect the interaction of the products with DNA. The dose-response curve obtained with benzo(a)pyrene incubated 24 h at pH 4.7 was different from that of the parent compound indicating a different type of interaction with DNA. A DNA hybridisation sensor was also assembled using a thiolated/biotynilated 24-mer oligonucleotide immobilised on a gold screen-printed electrode and avidin-alkaline phosphatase conjugate. A voltammetric detection of naphtol was used to detect the hybridisation reaction. A net inhibition of the hybridisation reaction was observed after incubation with benzo(a)pyrene oxidation products that was attributed to the formation of stable adducts with the guanines of the biotinylated strand. LC-MS-MS studies of the oxidation products confirmed the presence of chemical species potentially forming adducts with DNA. The data reported demonstrate that DNA electrochemical sensors have the potential to be used to monitor remediation processes and to assess the potential toxicity vs. DNA of chemicals forming stable DNA adducts.
Topics: Benzopyrenes; Biosensing Techniques; Conductometry; DNA; Equipment Design; Equipment Failure Analysis; Light; Oligonucleotide Array Sequence Analysis; Reproducibility of Results; Sensitivity and Specificity
PubMed: 22078075
DOI: 10.1016/j.bios.2011.10.030 -
Biochemistry Mar 1980
Topics: 7,8-Dihydro-7,8-dihydroxybenzo(a)pyrene 9,10-oxide; Benzopyrenes; Cell Line; Cell Survival; DNA; Humans; Kinetics; Lung
PubMed: 6768383
DOI: 10.1021/bi00547a008 -
Journal of the American Chemical Society Sep 2001Photolabile 6-nitrobenzo[a]pyrene (6-nitroBaP) released nitric oxide (NO) under visible-light irradiation. The generation of NO and the concomitant formation of the...
Photolabile 6-nitrobenzo[a]pyrene (6-nitroBaP) released nitric oxide (NO) under visible-light irradiation. The generation of NO and the concomitant formation of the 6-oxyBaP radical were confirmed by ESR. BaP quinones were also detected as further oxidized products of the 6-oxyBaP radical. No such photodegradation was observed with other nitrated BaPs, such as 1-nitroBaP and 3-nitroBaP. DNA-strand breakage, caused by photoexcited 6-nitroBaP, was closely related to its NO-releasing activity. MO calculations of nitrated BaP suggest that the perpendicular conformation of the nitro substituent to the aromatic ring is important for the release of NO with light. These findings may be useful for the development of a new type of NO donor.
Topics: Benzopyrenes; DNA; Light; Nitric Oxide; Photochemistry
PubMed: 11535070
DOI: 10.1021/ja0109038 -
Carcinogenesis Sep 1991The synthesis of 4,5-difluorobenzo[a]pyrene, as a fluorinated probe to investigate the involvement of the K-region in the further metabolic activation of benzo[a]pyrene...
The synthesis of 4,5-difluorobenzo[a]pyrene, as a fluorinated probe to investigate the involvement of the K-region in the further metabolic activation of benzo[a]pyrene metabolites, is described. Benzo[a]pyrene-4,5-dione obtained from 2,3-dichloro-5,6-dicyano-1,4-benzoquinone oxidation of cis-4,5-dihydro-4,5-dihydroxybenzo[a]pyrene was fluorinated with dimethylaminosulfur trifluoride to give 4H,5H,4,4,5,5,-tetra-fluorobenzo[a]pyrene. Defluorination using lithium aluminum hydride in tetrahydrofuran gave 4,5,-difluorobenzo[a]pyrene.
Topics: Benzo(a)pyrene; Benzopyrenes
PubMed: 1893523
DOI: 10.1093/carcin/12.9.1647 -
Nature Sep 1946
Topics: Benzopyrenes; Biochemical Phenomena; In Vitro Techniques
PubMed: 20999098
DOI: 10.1038/158417a0 -
Environmental Health Perspectives Sep 1983The risk of lung cancer related to asbestos exposure has been shown to increase disproportionately by cigarette smoking, suggesting a synergistic effect. Differing...
The risk of lung cancer related to asbestos exposure has been shown to increase disproportionately by cigarette smoking, suggesting a synergistic effect. Differing lengths of NIEHS chrysotile with benzopyrene [B(a)P, B(e)P] (organic by-products of combustion) were applied on normal human fibroblasts (cell line CI) to test for cytotoxicity (survival determined by colony-forming efficiency), binding of benzopyrene to DNA, and the production of benzopyrene metabolites. At concentrations of 100 micrograms/mL, NIEHS short chrysotile was more cytotoxic than NIEHS intermediate chrysotile (3% and 17% survival, respectively); B(a)P and B(e)P concentrations up to and including 10 microM were not cytotoxic. Simultaneous application of NIEHS short chrysotile with B(a)P or B(e)P did not decrease survival synergistically. On the contrary, application of B(a)P simultaneously with NIEHS intermediate chrysotile resulted in increased survival over that of intermediate chrysotile alone (25% and 17% survival, respectively). There were low levels of B(a)P bound to DNA in the presence of NIEHS short chrysotile or NIEHS intermediate chrysotile. Measurable levels of B(a)P-DNA adducts were formed both in the absence and in the presence of each size of NIEHS chrysotile. However, there was no strong indication of a perturbation of the level of DNA-B(a)P binding following simultaneous administration of increasing levels of asbestos in addition to 1 microM hydrocarbon. The asbestos had no demonstrable influence on the level of B(a)P metabolism during the 24-hr period following simultaneous exposure of asbestos and hyrdocarbons.(ABSTRACT TRUNCATED AT 250 WORDS)
Topics: Asbestos; Asbestos, Serpentine; Benzo(a)pyrene; Benzopyrenes; Cell Survival; Cells, Cultured; DNA; Drug Interactions; Fibroblasts; Humans; Male
PubMed: 6315368
DOI: 10.1289/ehp.8351257 -
Biochemical Society Transactions Aug 1992
Topics: Animals; Aryl Hydrocarbon Hydroxylases; Benzopyrenes; Biological Transport; Cell Division; Cell Line; Humans; Kinetics; Mice; Microsomes
PubMed: 1426564
DOI: 10.1042/bst020279s -
Nature 1945
Topics: Benzopyrenes; Coal Tar
PubMed: 21006482
DOI: No ID Found -
Die Naturwissenschaften Oct 1974
Topics: Animals; Benzopyrenes; Female; Mice; Neoplasms; Putrescine
PubMed: 4420985
DOI: 10.1007/BF00597218 -
Journal of the National Cancer Institute Sep 1957
Topics: Animals; Benzopyrenes; Carcinogenesis; Neoplasms, Experimental; Smoking
PubMed: 13502721
DOI: 10.1093/jnci/19.3.361