Transformation of Photoluminescence Spectra at the Liposomal Encapsulation of Quantum Dots

Abstract

Semiconductor quantum dots (QDs) have been extensively used for biomedical applications as efficient biomarkers and biosensors. The liposome encapsulation presents an alternative method for quantum dots labeling to facilitate intracellular delivery of the QDs systems. The semiconductor CdSe/ZnS core/shell quantum dots of two different emission wavelengths (530 and 640nm) were encapsulated in liposomes prepared using a new " chemically green " method: by sonication and freezing-unfreezing procedure and without organic solvents application. The QDs-liposomes hybrids were studied by photoluminescence (PL) spectroscopy before and after quantum dots encapsulation. The liposomes encapsulation of both sizes of quantum dots changes of photoluminescence spectra up to higher emission energies. The advantages of CdSe/ZnS core/shell QDs encapsulation on " green " liposomes may be promising in biomedical applications as efficient biomarkers with water dispersability. At the same time, the energy change of QDs emission due to liposome encapsulation may be interesting for biosensoring applications.