title: Assessment of ionic liquids' toxicity through the inhibition of acylase I activity on a microflow system.
abstract: Acylase I (ACY I) plays a role in the detoxication and bioactivation of xenobiotics as well in other physiological functions. In this context, an automated ACY I assay for the evaluation of ionic liquids' (ILs) toxicity was developed. The assay was implemented in a sequential injection analysis (SIA) system and was applied to eight commercially available ILs. The SIA methodology was based on the deacetylation of N-acetyl-l-methionine with production of l-methionine, which was determined using fluorescamine. ACY I inhibition in the presence of ILs was monitored by the decrease of fluorescence intensity. The obtained results confirmed the influence of ILs' structural elements on its toxicity and revealed that pyridinium and phosphonium cations, longer alkyl side chains and tetrafluoroborate anion displayed higher toxic effect on enzyme activity. The developed methodology proved to be robust and exhibited good repeatability (RSD < 1.3%, n = 10), leading also to a reduction of reagents consumption and effluents production. Thus, it is expected that the proposed assay can be used as a novel tool for ILs' toxicity screening.
authors.affiliation: LAQV, REQUIMTE, Departamento de Ciências Químicas, Faculdade de Farmácia, Universidade do Porto, Rua Jorge Viterbo Ferreira, 228, 4050-313 Porto, Portugal.
authors.forename: Ana M O
authors.initials: AMO
authors.lastname: Azevedo
authors.affiliation: LAQV, REQUIMTE, Departamento de Ciências Químicas, Faculdade de Farmácia, Universidade do Porto, Rua Jorge Viterbo Ferreira, 228, 4050-313 Porto, Portugal; Escola Superior de Saúde, Instituto Politécnico da Guarda, Avenida Rainha D. Amélia, S/N, 6300-749 Guarda, Portugal.
authors.forename: Sarah A P
authors.initials: SAP
authors.lastname: Pereira
authors.affiliation: LAQV, REQUIMTE, Departamento de Ciências Químicas, Faculdade de Farmácia, Universidade do Porto, Rua Jorge Viterbo Ferreira, 228, 4050-313 Porto, Portugal.
authors.forename: Marieta L C
authors.initials: MLC
authors.lastname: Passos
authors.affiliation: LAQV, REQUIMTE, Departamento de Ciências Químicas, Faculdade de Farmácia, Universidade do Porto, Rua Jorge Viterbo Ferreira, 228, 4050-313 Porto, Portugal.
authors.forename: Susana P F
authors.initials: SPF
authors.lastname: Costa
authors.affiliation: LAQV, REQUIMTE, Departamento de Ciências Químicas, Faculdade de Farmácia, Universidade do Porto, Rua Jorge Viterbo Ferreira, 228, 4050-313 Porto, Portugal; A3D - Association for Drug Discovery and Development, Aveiro, Portugal.
authors.forename: Paula C A G
authors.initials: PCAG
authors.lastname: Pinto
authors.affiliation: LAQV, REQUIMTE, Departamento de Ciências Químicas, Faculdade de Farmácia, Universidade do Porto, Rua Jorge Viterbo Ferreira, 228, 4050-313 Porto, Portugal; Unidade de Investigação para o Desenvolvimento do Interior, Instituto Politécnico da Guarda, Avenida Dr. Francisco de Sá Carneiro, 50, 6300-559 Guarda, Portugal.
authors.forename: André R T S
authors.initials: ARTS
authors.lastname: Araujo
authors.affiliation: LAQV, REQUIMTE, Departamento de Ciências Químicas, Faculdade de Farmácia, Universidade do Porto, Rua Jorge Viterbo Ferreira, 228, 4050-313 Porto, Portugal. Electronic address: lsaraiva@ff.up.pt.
authors.forename: M Lúcia M F S
authors.initials: MLMFS
authors.lastname: Saraiva
mesh_terms: D000581:Amidohydrolases / Q000378:metabolism*; D000838:Anions / Q000737:chemistry; D001681:Biological Assay / Q000379:methods*; D002412:Cations / Q000737:chemistry; D052578:Ionic Liquids / Q000737:chemistry / Q000633:toxicity*; D008715:Methionine / Q000031:analogs & derivatives / Q000378:metabolism
chemical_list: D000838:Anions; D002412:Cations; D052578:Ionic Liquids; C006379:N-acetylmethionine; D008715:Methionine; D000581:Amidohydrolases; C019672:aminoacylase I
keywords: Acylase I; Automated; Ionic liquids; SIA; Toxicity