Details

Autor(en) / Beteiligte

• Mozafari, Masoud
• Moztarzadeh, Fathollah
• Seifalian, Alexander M.
• Tayebi, Lobat

Titel

Self-assembly of PbS hollow sphere quantum dots via gas–bubble technique for early cancer diagnosis

Ist Teil von

• Journal of luminescence, 2013-01, Vol.133 (1), p.188-193

Ort / Verlag

Amsterdam: Elsevier B.V

Erscheinungsjahr

2013

Link zum Volltext

Quelle

Elsevier ScienceDirect Journals Complete

Beschreibungen/Notizen

• Quantum dots (QDs) with their unique optical properties have attracted widespread interest in cancer diagnosis and therapy. Due to their ability to absorb and emit light very efficiently, lead sulfide (PbS) hollow spheres with nanometer-to-micrometer dimensions having tailored structural, optical, and surface properties represent an important class of QDs that are potentially useful for early cancer detection. In this study, PbS hollow sphere QDs have been successfully synthesized using a template-free and green method. The formation of hollow structures was explained by a gas–liquid interface aggregation mechanism, in which the formation of SO2 gas bubbles plays a key role. The synthesized samples were characterized by X-ray diffraction (XRD), transmission electron microscopy (TEM), scanning electron microscopy (SEM), energy dispersive X-ray analyzer (EDX), photoluminescence (PL) and Fourier transform infrared spectroscopy (FTIR). The results demonstrate that the PbS hollow spheres possess good optical quality with strong luminescence properties, which indicate their capabilities for the simultaneous detection of multiple cancer biomarkers in blood assays and cancer tissue biopsies. The hollow structures were formed by gas–liquid interface aggregation mechanism, in which the formation of SO2 gas bubbles played a key role. When the SO2 gas bubbles generated in the liquid phase, they created numerous gas–liquid interfaces inside the solution phase. Then, the gas–liquid interfaces served as the nucleation or agglomeration centers for the PbS NCs. In addition, the PbS hollow sphere QDs possess strong optical properties, which indicate their capabilities for cancer diagnosis and therapy. [Display omitted] ► Large quantities of SO2 bubbles produced in the reaction system serve as the aggregation centers. ► After the initial nucleation, monomers would grow into NCs, which have a tendency to aggregate. ► Due to the minimization of interfacial energy, NCs aggregate around the gas–liquid interface. ► High emission intensity suggests immense potential of PbS QDs in early detection of cancer tumors.