Wide visible-range activatable fluorescence ZnSe:Eu3+/Mn2+@ZnS quantum dots: local atomic structure order and application as a nanoprobe for bioimaging

Autor(es)

Khan, Zahid Ullah ^{[1, 2]} ; Uchiyama, Mayara Klimuk ^[1] ; Khan, Latif Ullah ^{[1, 3]} ; Araki, Koiti ^[1] ; Goto, Hiro ^[4] ; Franca Cunha Felinto, Maria Claudia ^[5] ; de Souza, Ana Olivia ^[6] ; de Brito, Hermi Felinto ^[1] ; Gidlund, Magnus ^[2]

Afiliação do(s) autor(es)

^[1] Univ Sao Paulo, Dept Fundamental Chem, Inst Chem, BR-05508000 Sao Paulo, SP - Brazil

^[2] Univ Sao Paulo, Inst Biomed Sci 4, Dept Immunol, BR-05508000 Sao Paulo, SP - Brazil

^[3] Synchrotron Light Expt Sci & Applicat Middle East, POB 7, Allan 19252 - Jordan

^[4] Univ Sao Paulo, Fac Med, BR-05403000 Sao Paulo, SP - Brazil

^[5] Univ Sao Paulo, Inst Nucl Energy & Res, BR-05508000 Sao Paulo, SP - Brazil

^[6] Butantan Inst, Dev & Innovat Lab, BR-05503900 Sao Paulo, SP - Brazil

• Tipo de documento: Artigo Científico
• Fonte: JOURNAL OF MATERIALS CHEMISTRY B; DEC 2021.
• Citações Web of Science: 0

Resumo

The development of QDs-based fluorescent bionanoprobe for cellular imaging fundamentally relies upon the precise knowledge of particle-cell interaction, optical properties of QDs inside and outside of the cell, movement of a particle in and out of the cell, and the fate of particle. We reported engineering and physicochemical characterization of water-dispersible Eu3+/Mn2+ co-doped ZnSe@ZnS core/shell QDs and studied their potential as a bionanoprobe for biomedical applications, evaluating their biocompatibility, fluorescence behaviour by CytoViva dual mode fluorescence imaging, time-dependent uptake, endocytosis and exocytosis in RAW 264.7 macrophages. The oxidation state and local atomic structure of the Eu dopant studied by X-ray absorption fine structure (XAFS) analysis manifested that the Eu3+ ions occupied sites in both ZnSe and ZnS lattices for the core/shell QDs. A novel approach was developed to relieve the excitation constraint of wide bandgap ZnSe by co-incorporation of Eu3+/Mn2+ codopants, enabling the QDs to be excited at a wide UV-visible range. The QDs displayed tunable emission colors by a gradual increase in Eu3+ concentration at a fixed amount of Mn2+, systematically enhancing the Mn2+ emission intensity via energy transfer from the Eu3+ to Mn2+ ion. The ZnSe:Eu3+/Mn2+@ZnS QDs presented high cell viability above 85% and induced no cell activation. The detailed analyses of QDs-treated cells by dual mode fluorescence CytoViva microscopy confirmed the systematic color-tunable fluorescence and its intensity enhances as a function of incubation time. The QDs were internalized by the cells predominantly via macropinocytosis and other lipid raft-mediated endocytic pathways, retaining an efficient amount for 24 h. The unique color tunability and consistent high intensity emission make these QDs useful for developing a multiplex fluorescent bionanoprobe, activatable in wide-visible region. (AU)

• Processo FAPESP: 21/00356-6 - Quantum dots com fluorescência multifuncional como amplificadores para a geração 1O2 e terapia fotodinâmica aprimorada sinérgica
• Beneficiário: Zahid Ullah Khan
• Modalidade de apoio: Bolsas no Brasil - Pós-Doutorado