Assessing the effects of surfactants on the physical properties of liposome membranes

• Type: Article in International Scientific Journal
• Date: 2007

Authors

Joana Marcelino (Author) Other; Jose L F C Lima (Author) FFUP; Salette Reis (Author) FFUP; Carla Matos (Author) Other

Journal

Title: Chemistry and Physics of Lipids

Vol. 146 No. 2

Pages: 94-103

ISSN: 0009-3084

Publisher: Elsevier

Indexing

ISI Web of Knowledge - 35 Citations

ISI Web of Science

Scopus - 36 Citations

Scientific classification

CORDIS: Health sciences

FOS: Natural sciences > Biological sciences

Other information

Authenticus ID: P-004-ARJ

DOI: 10.1016/j.chemphyslip.2006.12.008

Resumo (PT): Knowledge of the partition process of environmentally significant molecules between biological membranes and their surroundings is of vital importance to explain their activity and toxicity, as well as phenomena like absorption, distribution and metabolism. In this research effort, we have studied membrane interactions of three surfactants: t-octylphenoxypolyethoxyethanol (Triton X-100), cetyltrimethylammonium chloride (CTAC) and dodecylbenzene sulphonate (SDBS). Unilamellar liposomes (LUVs) of egg yolk phosphatidylcholine (EPC) were used as membrane models. The partition coefficient, a fundamental parameter in assessing the behaviour of xenobiotic compounds, was determined for SDBS and Triton X-100 by derivative spectrophotometry and fluorescence quenching. The effect of these surfactants upon the physico-chemical characteristics (fluidity, diameter and surface charge) of the liposome membrane was also determined. Results show that all the three surfactants cause an increase in fluidity of the liposome membrane, although for low surfactant concentrations uncharacteristic membrane rigidity was observed, probably due to a change in lipid packing density. <br> <br> Keywords: Liposomes; Detergent partitioning; Derivative spectrophotometry; Fluorescence quenching; Anisotropy <br> <a target="_blank" href="http://www.sciencedirect.com/science?_ob=ArticleURL&_udi=B6T2N-4MSXT8G-1&_user=2460038&_coverDate=04%2F30%2F2007&_rdoc=4&_fmt=high&_orig=browse&_srch=doc-info(%23toc%234923%232007%23998539997%23645038%23FLA%23display%23Volume)&_cdi=4923&_sort=d&_docanchor=&_ct=7&_acct=C000057398&_version=1&_urlVersion=0&_userid=2460038&md5=b1f3948b8d3dfebf1a4d7d5aaeb9d57d"> Texto integral</a> <br> <br>

Abstract (EN): Knowledge of the partition process of environmentally significant molecules between biological membranes and their surroundings is of vital importance to explain their activity and toxicity, as well as phenomena like absorption, distribution and metabolism. In this research effort, we have studied membrane interactions of three surfactants: t-octylphenoxypolyethoxyethanol (Triton X-100), cetyltrimethylammonium chloride (CTAC) and dodecylbenzene sulphonate (SDBS). Unilamellar liposomes (LUVs) of egg yolk phosphatidylcholine (EPC) were used as membrane models. The partition coefficient, a fundamental parameter in assessing the behaviour of xenobiotic compounds, was determined for SDBS and Triton X-100 by derivative spectrophotornetry and fluorescence quenching. The effect of these surfactants upon the physico-chemical characteristics (fluidity, diameter and surface charge) of the liposome membrane was also determined. Results show that all the three surfactants cause an increase in fluidity of the liposome membrane, although for low surfactant concentrations uncharacteristic membrane rigidity was observed, probably due to a change in lipid packing density.

Language: English

Type (Professor's evaluation): Scientific

No. of pages: 10