Europium chelate-loaded liposomes

A tool for the study of binding and integrity of liposomes

Adelina Orellana (Corresponding Author), Marja-Leena Laukkanen, Kari Keinänen

Research output: Contribution to journalArticleScientificpeer-review

12 Citations (Scopus)

Abstract

Using the biotin-streptavidin interaction as a model, we investigated the suitability of lanthanide chelates as encapsulated liposomal labels in liposome-based binding assays. Large unilamellar phospholipid:cholesterol liposomes containing europium-DTPA chelate and biotinylated phosphatidylethanolamine were prepared by detergent dialysis. The resulting Eu-liposomes (⊘120 nm) bound specifically to streptavidin in microtiter wells as measured by time-resolved fluorometric assay (TRF). The intensity of fluorescence released from the bound liposomes was dependent on the concentration of biotin in the liposome membrane, the concentration of europium entrapped in the liposomes, the incubation time and the amount of liposomes used in the assay. The sensitivity of the TRF assay allowed the detection of binding of attomole quantities of liposomes. The streptavidin-immobilised liposomes subjected to porcine pancreatic phospholipase A2 (EC 3.1.1.4) and detergents displayed a dose-dependent release of the encapsulated europium. Lanthanide-chelate-liposomes should prove useful for studies addressing binding and stability of liposomes.
Original languageEnglish
Pages (from-to)29-34
Number of pages6
JournalBiochimica et Biophysica Acta
Volume1284
Issue number1
DOIs
Publication statusPublished - 1996
MoE publication typeA1 Journal article-refereed

Fingerprint

Europium
Liposomes
Assays
Streptavidin
Lanthanoid Series Elements
Biotin
Detergents
Pentetic Acid
Dialysis
Phospholipases A2
Labels
Phospholipids
Swine

Cite this

Orellana, Adelina ; Laukkanen, Marja-Leena ; Keinänen, Kari. / Europium chelate-loaded liposomes : A tool for the study of binding and integrity of liposomes. In: Biochimica et Biophysica Acta. 1996 ; Vol. 1284, No. 1. pp. 29-34.
@article{b507b6b436bb452e8e5bcacbbb6362b1,
title = "Europium chelate-loaded liposomes: A tool for the study of binding and integrity of liposomes",
abstract = "Using the biotin-streptavidin interaction as a model, we investigated the suitability of lanthanide chelates as encapsulated liposomal labels in liposome-based binding assays. Large unilamellar phospholipid:cholesterol liposomes containing europium-DTPA chelate and biotinylated phosphatidylethanolamine were prepared by detergent dialysis. The resulting Eu-liposomes (⊘120 nm) bound specifically to streptavidin in microtiter wells as measured by time-resolved fluorometric assay (TRF). The intensity of fluorescence released from the bound liposomes was dependent on the concentration of biotin in the liposome membrane, the concentration of europium entrapped in the liposomes, the incubation time and the amount of liposomes used in the assay. The sensitivity of the TRF assay allowed the detection of binding of attomole quantities of liposomes. The streptavidin-immobilised liposomes subjected to porcine pancreatic phospholipase A2 (EC 3.1.1.4) and detergents displayed a dose-dependent release of the encapsulated europium. Lanthanide-chelate-liposomes should prove useful for studies addressing binding and stability of liposomes.",
author = "Adelina Orellana and Marja-Leena Laukkanen and Kari Kein{\"a}nen",
note = "Project code: BEL2031",
year = "1996",
doi = "10.1016/0005-2736(96)00104-6",
language = "English",
volume = "1284",
pages = "29--34",
journal = "Biochimica et Biophysica Acta: General Subjects",
issn = "0304-4165",
publisher = "Elsevier",
number = "1",

}

Europium chelate-loaded liposomes : A tool for the study of binding and integrity of liposomes. / Orellana, Adelina (Corresponding Author); Laukkanen, Marja-Leena; Keinänen, Kari.

In: Biochimica et Biophysica Acta, Vol. 1284, No. 1, 1996, p. 29-34.

Research output: Contribution to journalArticleScientificpeer-review

TY - JOUR

T1 - Europium chelate-loaded liposomes

T2 - A tool for the study of binding and integrity of liposomes

AU - Orellana, Adelina

AU - Laukkanen, Marja-Leena

AU - Keinänen, Kari

N1 - Project code: BEL2031

PY - 1996

Y1 - 1996

N2 - Using the biotin-streptavidin interaction as a model, we investigated the suitability of lanthanide chelates as encapsulated liposomal labels in liposome-based binding assays. Large unilamellar phospholipid:cholesterol liposomes containing europium-DTPA chelate and biotinylated phosphatidylethanolamine were prepared by detergent dialysis. The resulting Eu-liposomes (⊘120 nm) bound specifically to streptavidin in microtiter wells as measured by time-resolved fluorometric assay (TRF). The intensity of fluorescence released from the bound liposomes was dependent on the concentration of biotin in the liposome membrane, the concentration of europium entrapped in the liposomes, the incubation time and the amount of liposomes used in the assay. The sensitivity of the TRF assay allowed the detection of binding of attomole quantities of liposomes. The streptavidin-immobilised liposomes subjected to porcine pancreatic phospholipase A2 (EC 3.1.1.4) and detergents displayed a dose-dependent release of the encapsulated europium. Lanthanide-chelate-liposomes should prove useful for studies addressing binding and stability of liposomes.

AB - Using the biotin-streptavidin interaction as a model, we investigated the suitability of lanthanide chelates as encapsulated liposomal labels in liposome-based binding assays. Large unilamellar phospholipid:cholesterol liposomes containing europium-DTPA chelate and biotinylated phosphatidylethanolamine were prepared by detergent dialysis. The resulting Eu-liposomes (⊘120 nm) bound specifically to streptavidin in microtiter wells as measured by time-resolved fluorometric assay (TRF). The intensity of fluorescence released from the bound liposomes was dependent on the concentration of biotin in the liposome membrane, the concentration of europium entrapped in the liposomes, the incubation time and the amount of liposomes used in the assay. The sensitivity of the TRF assay allowed the detection of binding of attomole quantities of liposomes. The streptavidin-immobilised liposomes subjected to porcine pancreatic phospholipase A2 (EC 3.1.1.4) and detergents displayed a dose-dependent release of the encapsulated europium. Lanthanide-chelate-liposomes should prove useful for studies addressing binding and stability of liposomes.

U2 - 10.1016/0005-2736(96)00104-6

DO - 10.1016/0005-2736(96)00104-6

M3 - Article

VL - 1284

SP - 29

EP - 34

JO - Biochimica et Biophysica Acta: General Subjects

JF - Biochimica et Biophysica Acta: General Subjects

SN - 0304-4165

IS - 1

ER -