Sequential injection system for phospholipase A(2) activity evaluation: Studies on liposomes using an environment-sensitive fluorescent probe

• Type: Article in International Scientific Journal
• Date: 2009

Authors

Andre R T S Araujo (Author) Other; Diana Gaspar (Author) Other; Marlene Lucio (Author) FFUP; Salette Reis (Author) FFUP; Lucia L M F S Saraiva (Author) FFUP; Jose L F C Lima (Author) FFUP

Journal

Title: Talanta

Vol. 79 No. 4

Pages: 1125-1129

ISSN: 0039-9140

Publisher: Elsevier

Indexing

ISI Web of Knowledge - 3 Citations

Scopus - 4 Citations

Pubmed / Medline

Scientific classification

FOS: Natural sciences > Chemical sciences

CORDIS: Health sciences

Other information

Authenticus ID: P-003-FSJ

DOI: 10.1016/j.talanta.2009.03.029

Resumo (PT): This work reports the development of an automatic methodology based on the use of 1-anilinonaphthalene-8-sulfonate (ANS) as an interfacial fluorescent probe for detecting the hydrophobic environment shift around the probe, caused by the hydrolytic action of PLA2 on the liposomes. The implementation of this reaction in a sequential injection analysis (SIA) system along with the use of the mixing chambers permitted the evaluation of PLA2 activity and assessment of the inhibitory effect of the non-steroidal anti-inflammatory drugs (NSAIDs) on PLA2 activity. Several studies were performed with the aim of establishing the appropriate flow system configuration: the liposome substrate; PLA2 and ANS optimum concentrations and incubation times before and after the enzyme addition. Based on these studies, the optimum reaction conditions were selected. It was shown that PLA2 is effectively inhibited by the NSAIDs tested (meloxicam, tolmetin and ibuprofen) and by the α-lipoic acid, used as a positive control. Results obtained from the flow system are in agreement with those provided by the comparison batch procedures. The proposed methodology is in fact more efficient and rapid than the comparison batch experiments, enabling the exact timing of fluidic manipulations and precise control of the reaction conditions. <br> <br> Keywords: SIA; Fluorescence; ANS; Liposomes; Phospholipase A2; Anti-inflammatory drugs <br> <a target="_blank" href="http://www.sciencedirect.com/science?_ob=ArticleURL&_udi=B6THP-4VXDTRW-4&_user=2460038&_coverDate=09%2F15%2F2009&_rdoc=28&_fmt=high&_orig=browse&_srch=doc-info(%23toc%235288%232009%23999209995%231318055%23FLA%23display%23Volume)&_cdi=5288&_sort=d&_docanchor=&_ct=37&_acct=C000057398&_version=1&_urlVersion=0&_userid=2460038&md5=33d424711f5f707dfb4e6dcac7281fb0 "> Texto integral</a> <br> <br>

Abstract (EN): This work reports the development of an automatic methodology based on the use of 1-anilinonaphtlhalene-8-sulfonate (ANS) as an interfacial fluorescent probe for detecting the hydrophobic environment shift around the probe, caused by the hydrolytic action of PLA(2) on the liposomes. The implementation of this reaction in a sequential injection analysis (SIA) system along with the use of the mixing chambers permitted the evaluation of PLA(2) activity and assessment of the inhibitory effect of the non-steroidal anti-inflammatory drugs (NSAIDs) on PLA(2) activity. Several studies were performed with the aim of establishing the appropriate flowsystem configuration: the liposome substrate; PLA(2) and ANS optimum concentrations and incubation times before and after the enzyme addition. Based on these studies, the optimum reaction conditions were selected. It was shown that PLA(2) is effectively inhibited by the NSAIDs tested (meloxicam, tolmetin and ibuprofen) and by the alpha-lipoic acid, used as a positive control. Results obtained from the flow system are in agreement with those provided by the comparison batch procedures. The proposed methodology is in fact more efficient and rapid than the comparison batch experiments, enabling the exact timing of fluidic manipulations and precise control of the reaction conditions.

Language: English

Type (Professor's evaluation): Scientific

No. of pages: 5