Genotoxicity modulation of 1-Nitropyrene by multiwalled carbon nanotubes

Author(s)

Jaqueline Gonçalves Honório

• Document type: Master's Dissertation
• Press: Limeira, SP.
• Institution: Universidade Estadual de Campinas (UNICAMP). Faculdade de Tecnologia
• Defense date: 2012-04-27

Examining board members

Gisela de Aragão Umbuzeiro; Silvia Regina Batistuzzo de Medeiros; Diego Stafani Teodoro Martinez

• Advisor: Gisela de Aragão Umbuzeiro; Vitor Rafael Coluci

Abstract

Nanomaterials, such as multi-wall carbon nanotubes (MWCNT) have been shown potential to remediate soil or water polluted with organic compounds because of their high specific-surface area, which can enhance the ability of the CNT to adsorb organics. Although treatment of MWCNT with nitric acid can increase the water solubility of MWCNT by introducing oxygenated groups such as carboxylic acids onto the surface, it may have the unintended consequence of decreasing the ability of MWCNT to interact with organic molecules. To investigate this possibility, we evaluated the ability of acid-treated MWCNT to absorb a common environmental pollutant, 1- nitropyrene (1-NP), which is a highly mutagenic and carcinogenic nitro-polycyclic aromatic hydrocarbon. Different doses of well-characterized MWCNTs were tested with different doses of 1-NP, and the detection of the non-adsorbed 1-NP was assessed by the Salmonella mutagenicity assay in strain TA98, which is highly sensitive to 1-NP. Thus, only free 1-NP not bound to the MWCNT was able to enter the bacteria and induce mutagenesis. We found an inverse association between the amount of oxidation by nitric-acid treatment of the MWCNT and the amount of mutagenicity of the reaction mixture. Our data suggest that acid treatment of MWCNT may, in fact, reduce the ability of MWCNT to bind organic pollutants, reducing their effectiveness for remediation (AU)

• FAPESP's process: 10/02803-5 - Modulation of the eco/genotoxicity of nitroaminobenzene dyes by multi walled carbon nanotubes
• Grantee: Jaqueline Gonçalves Honório
• Support Opportunities: Scholarships in Brazil - Master