Nano-scale liposomal container with a «signal system» for substances delivering in living cells

S L Yefimova,A S Lebed,A V Sorokin,Yu V Malyukin,G Ya Guralchuk,N S Kavok,I Yu Kurilchenko

doi:10.7124/bc.000081

Abstract

Aim. The aim of this research is to study the possibility to supply the nano-scale liposomal «container», used for the targeted substance delivery inside the living cells, with a «signal system» to trace the liposome fate in real time. Methods. For this purpose, the methods of fluorescence microscopy, fluorescence spectroscopy and microspectroscopy have been used. Results. The cellular uptake of hydrophobic fluorescent probes DiO and DiI, preloaded in phosphatidylcholine (PC) liposomes, in real time has been studied using fluorescence resonance energy transfer (FRET) from the donor probe DiO to the acceptor one DiI. It has been revealed that after 3 hours incubation of hepatocytes with FRET liposomes, the FRET signal almost disappears, whereas DiO fluorescence becomes very intensive. Conclusions. The loss of FRET signal could be used as a «signal system» to monitor the cell-liposome fusion and delivery of any active compounds to cells.

Highlights

Among the widely studied drug delivery vehicles, liposomal ones are of special interest due to their attractive properties [1,2,3]
We investigate in real time the cellular uptake of hydrophobic fluorescent probes preloaded in phosphatidylcholine (PC) liposomes
Forced concentration of hydrophobic fluorescent probes in liposome lipid bilayers ensures the required distance between the donor dioctadecyloxacarbocyanine perchlorate (DiO) and acceptor DiI to observe fluorescence resonance energy transfer (FRET) (Fig. 2, curve 3)

Summary

Introduction

Among the widely studied drug delivery vehicles, liposomal ones are of special interest due to their attractive properties [1,2,3]. Liposomes can provide targeted delivery of active compounds into sites of. Fluorescent imaging has become an invaluable tool in biomedical researches that can trace the liposome fate in a living cell and help answer many questions including the pathway for cellular internalization of liposomes and incorporated active compounds. For this purpose, a liposome should be supplied with special «signal system» that traces the liposome fate and visualizes the active compound release. Fluorescent probes can play this role [4]

Objectives

Results

Conclusion