Automated evaluation of the effect of ionic liquids on catalase activity

• Type: Article in International Scientific Journal
• Date: 2011

Authors

Paula C A G Pinto (Author) FFUP; Andreia D F Costa (Author) Other; Jose L F C Lima (Author) FFUP; Lucia L M F S Saraiva (Author) FFUP

Journal

Title: Chemosphere

Vol. 82 No. 11

Pages: 1620-1628

ISSN: 0045-6535

Publisher: Elsevier

Indexing

ISI Web of Knowledge - 32 Citations

ISI Web of Science

Scopus - 39 Citations

Pubmed / Medline

Scientific classification

FOS: Natural sciences > Earth and related Environmental sciences

CORDIS: Health sciences

Other information

Authenticus ID: P-002-TJH

DOI: 10.1016/j.chemosphere.2010.11.046

Resumo (PT): An automated assay for the evaluation of the influence of ionic liquids on the activity of catalase was developed. The activity and inhibition assays were implemented in a sequential injection analysis (SIA) system and intended to contribute for the estimation of the toxicity of the tested compounds. The fast developed methodology was based on the oxidation of the non-fluorescent probe amplex red, in the presence of H2O2, to produce resorufin, a strong fluorescent compound. Catalase activity was monitored by the decreased of the fluorescence intensity due to the consumption of H2O2 by the enzyme. The activity assays were performed in strictly aqueous media and in the presence of increasing concentrations of seven commercially available ionic liquids and sodium azide, a strong inhibitor of catalase. IC50 values between 0.15 and 2.77 M were obtained for the tested compounds, revealing distinct inhibitory effects. This allowed us to perform some considerations about the toxicity of the tested cations and anions. The developed SIA methodology showed to be robust and exhibited good repeatability in all the assay conditions. On the other hand, it proved to be in good agreement with the actual concerns of “Green Chemistry” since it involved the consumption of less than 200 μL of reagents and the production of only 1.7 mL of effluent (per cycle) and at the same time reduced the operator exposure resulting in increased environmental and human safety. <br> <br> Keywords: Ionic liquids; Toxicity; Catalase; SIA <br> <a target="_blank" href="http://www.sciencedirect.com/science/article/pii/S0045653510013536 "> Texto integral </a> <br> <br>

Abstract (EN): An automated assay for the evaluation of the influence of ionic liquids on the activity of catalase was developed. The activity and inhibition assays were implemented in a sequential injection analysis (SIA) system and intended to contribute for the estimation of the toxicity of the tested compounds. The fast developed methodology was based on the oxidation of the non-fluorescent probe amplex red, in the presence of H(2)O(2), to produce resorufin, a strong fluorescent compound. Catalase activity was monitored by the decreased of the fluorescence intensity due to the consumption of H(2)O(2) by the enzyme. The activity assays were performed in strictly aqueous media and in the presence of increasing concentrations of seven commercially available ionic liquids and sodium azide, a strong inhibitor of catalase. IC(50) values between 0.15 and 2.77 M were obtained for the tested compounds, revealing distinct inhibitory effects. This allowed us to perform some considerations about the toxicity of the tested cations and anions. The developed SIA methodology showed to be robust and exhibited good repeatability in all the assay conditions. On the other hand, it proved to be in good agreement with the actual concerns of "Green Chemistry" since it involved the consumption of less than 200 mu L of reagents and the production of only 1.7 mL of effluent (per cycle) and at the same time reduced the operator exposure resulting in increased environmental and human safety.

Language: English

Type (Professor's evaluation): Scientific

No. of pages: 9