TY  - JOUR
AU  - Milojkov, Dusan V.
AU  - Sokic, Miroslav
AU  - Radosavljevic-Mihajlović, Ana
AU  - Stanic, Vojislav
AU  - Manojlović, Vaso
AU  - Mutavdžić, Dragosav
AU  - Milanović, Marija
PY  - 2021
UR  - http://rimsi.imsi.bg.ac.rs/handle/123456789/1460
AB  - Coupled substitution of fluorapatite (FAP) crystal lattice plays an important role in the engineering of optically active nanomaterials. Uniform fluorapatite nanopowders doped with praseodymium (Pr3+) and carbonate (CO32-) ions have been successfully synthesized by precipitation method under room temperature (25 degrees C). The structural, morphological, chemical and optical properties of monophase material were characterized by X-ray diffraction (XRD), Fourier Transform Infrared and Far Infrared Spectroscopy (FTIR and FIR, respectively), Scanning Electron Microscopy with Energy Dispersive Spectroscopy (SEM/EDS), Transmission Electron Microscopy (TEM) and Photoluminescence Spectroscopy (PL). Coupled substitution of FAP crystal lattice with Pr3+ and CO32- reduces the crystallite size with a constant c/a ratio of 1.72. FTIR study showed that synthesized nanopowders were AB-type CO32- substitution, and FIR study revealed new Pr-O vibrations. TEM analysis was found that synthesized nanopowders were composed of irregular spheres in the nanometer range. The fluorescence of FAP nanoparticles was in the violet-blue region of the visible part of the spectrum. When Pr3+ was doped in a lattice, the violet-blue emission becomes sharper due to reabsorption. MCR-ALS analyses of fluorescence spectra indicated the shift of the maximum to the blue color with the increase in the concentration of Pr3+ ions. Additionally, luminescent nanopowders demonstrated significant antibacterial activity against Escherichia coli. As the obtained nanoparticles showed a good absorption of ultraviolet A light and reabsorption of blue-green luminescence, they are suitable for further development of optically active nanomaterials for light filtering. Optically active PrCFAP nanopowders with antibacterial properties may be promising additives for the development of multifunctional cosmetic and health care products.
PB  - MDPI, Basel
T2  - Metals
T1  - Influence of Pr3+ and CO32- Ions Coupled Substitution on Structural, Optical and Antibacterial Properties of Fluorapatite Nanopowders Obtained by Precipitation
IS  - 9
VL  - 11
DO  - 10.3390/met11091384
ER  - 

@article{
author = "Milojkov, Dusan V. and Sokic, Miroslav and Radosavljevic-Mihajlović, Ana and Stanic, Vojislav and Manojlović, Vaso and Mutavdžić, Dragosav and Milanović, Marija",
year = "2021",
abstract = "Coupled substitution of fluorapatite (FAP) crystal lattice plays an important role in the engineering of optically active nanomaterials. Uniform fluorapatite nanopowders doped with praseodymium (Pr3+) and carbonate (CO32-) ions have been successfully synthesized by precipitation method under room temperature (25 degrees C). The structural, morphological, chemical and optical properties of monophase material were characterized by X-ray diffraction (XRD), Fourier Transform Infrared and Far Infrared Spectroscopy (FTIR and FIR, respectively), Scanning Electron Microscopy with Energy Dispersive Spectroscopy (SEM/EDS), Transmission Electron Microscopy (TEM) and Photoluminescence Spectroscopy (PL). Coupled substitution of FAP crystal lattice with Pr3+ and CO32- reduces the crystallite size with a constant c/a ratio of 1.72. FTIR study showed that synthesized nanopowders were AB-type CO32- substitution, and FIR study revealed new Pr-O vibrations. TEM analysis was found that synthesized nanopowders were composed of irregular spheres in the nanometer range. The fluorescence of FAP nanoparticles was in the violet-blue region of the visible part of the spectrum. When Pr3+ was doped in a lattice, the violet-blue emission becomes sharper due to reabsorption. MCR-ALS analyses of fluorescence spectra indicated the shift of the maximum to the blue color with the increase in the concentration of Pr3+ ions. Additionally, luminescent nanopowders demonstrated significant antibacterial activity against Escherichia coli. As the obtained nanoparticles showed a good absorption of ultraviolet A light and reabsorption of blue-green luminescence, they are suitable for further development of optically active nanomaterials for light filtering. Optically active PrCFAP nanopowders with antibacterial properties may be promising additives for the development of multifunctional cosmetic and health care products.",
publisher = "MDPI, Basel",
journal = "Metals",
title = "Influence of Pr3+ and CO32- Ions Coupled Substitution on Structural, Optical and Antibacterial Properties of Fluorapatite Nanopowders Obtained by Precipitation",
number = "9",
volume = "11",
doi = "10.3390/met11091384"
}

Milojkov, D. V., Sokic, M., Radosavljevic-Mihajlović, A., Stanic, V., Manojlović, V., Mutavdžić, D.,& Milanović, M.. (2021). Influence of Pr3+ and CO32- Ions Coupled Substitution on Structural, Optical and Antibacterial Properties of Fluorapatite Nanopowders Obtained by Precipitation. in Metals
MDPI, Basel., 11(9).
https://doi.org/10.3390/met11091384

Milojkov DV, Sokic M, Radosavljevic-Mihajlović A, Stanic V, Manojlović V, Mutavdžić D, Milanović M. Influence of Pr3+ and CO32- Ions Coupled Substitution on Structural, Optical and Antibacterial Properties of Fluorapatite Nanopowders Obtained by Precipitation. in Metals. 2021;11(9).
doi:10.3390/met11091384 .

Milojkov, Dusan V., Sokic, Miroslav, Radosavljevic-Mihajlović, Ana, Stanic, Vojislav, Manojlović, Vaso, Mutavdžić, Dragosav, Milanović, Marija, "Influence of Pr3+ and CO32- Ions Coupled Substitution on Structural, Optical and Antibacterial Properties of Fluorapatite Nanopowders Obtained by Precipitation" in Metals, 11, no. 9 (2021),
https://doi.org/10.3390/met11091384 . .

TY  - JOUR
AU  - Milojkov, Dusan V.
AU  - Silvestre, Oscar F.
AU  - Stanic, Vojislav
AU  - Janjic, Goran V.
AU  - Mutavdžić, Dragosav
AU  - Milanović, Marija
AU  - Nieder, Jana B.
PY  - 2020
UR  - http://rimsi.imsi.bg.ac.rs/handle/123456789/1387
AB  - Fluorapatite doped with rare-earth elements has a wide-range of biomedical applications. Here, a new type of fluorapatite nanocrystals doped with praseodymium (FAP-Pr) with excitation-emission profiles in visible part of the spectrum is fabricated. Energy levels of Pr3+ activator ion contain metastable multiples states that offer the possibility of efficient multicolor emission lines in FAP nanocrystals. Three types of FAP-Pr nanocrystals with 0.1%, 0.5% and 1% atomic percent of Pr3+ (along with the undoped FAP control sample) are studied. Their novel chemical production method is described, the FAP-Pr nanocrystals structure, biocompatibility and the suitability for cell imaging are analyzed. Physicochemical characterization confirms crystals down to nanometer size. In addition, quantum-chemical calculation predicts that Pr3+ ions are incorporated into the FAP crystal lattice at Ca2 (6 h) sites. In vitro viability results shows that FAP-Pr nanocrystals are nontoxic to live cells. Additionally, the cell uptake of the FAP-Pr nanocrystals is studied using fluorescence-based widefield and confocal microscopy. The nanocrystals show characteristic green emission at 545 nm (P-3(0)-> H-3(5) transition of Pr3+ ion) and orange emission at 600 nm (D-1(2)-> H-3(4)), which we use to discriminate from cell autofluorescence background. Orthogonal projections across 3D confocal stacks show that the nanocrystals are able to enter the cells positioning themselves within the cytoplasm. Overall, the new FAP-Pr nanocrystals are biocompatible and of the tested types, the 0.5% Pr3+ doped nanocrystals show the highest promise as a tracking nanoparticle probe for bioimaging applications.
PB  - Amsterdam : Elsevier
T2  - Journal of Luminescence
T1  - Fabrication and characterization of luminescent Pr3+ doped fluorapatite nanocrystals as bioimaging contrast agents
VL  - 217
DO  - 10.1016/j.jlumin.2019.116757
ER  - 

@article{
author = "Milojkov, Dusan V. and Silvestre, Oscar F. and Stanic, Vojislav and Janjic, Goran V. and Mutavdžić, Dragosav and Milanović, Marija and Nieder, Jana B.",
year = "2020",
abstract = "Fluorapatite doped with rare-earth elements has a wide-range of biomedical applications. Here, a new type of fluorapatite nanocrystals doped with praseodymium (FAP-Pr) with excitation-emission profiles in visible part of the spectrum is fabricated. Energy levels of Pr3+ activator ion contain metastable multiples states that offer the possibility of efficient multicolor emission lines in FAP nanocrystals. Three types of FAP-Pr nanocrystals with 0.1%, 0.5% and 1% atomic percent of Pr3+ (along with the undoped FAP control sample) are studied. Their novel chemical production method is described, the FAP-Pr nanocrystals structure, biocompatibility and the suitability for cell imaging are analyzed. Physicochemical characterization confirms crystals down to nanometer size. In addition, quantum-chemical calculation predicts that Pr3+ ions are incorporated into the FAP crystal lattice at Ca2 (6 h) sites. In vitro viability results shows that FAP-Pr nanocrystals are nontoxic to live cells. Additionally, the cell uptake of the FAP-Pr nanocrystals is studied using fluorescence-based widefield and confocal microscopy. The nanocrystals show characteristic green emission at 545 nm (P-3(0)-> H-3(5) transition of Pr3+ ion) and orange emission at 600 nm (D-1(2)-> H-3(4)), which we use to discriminate from cell autofluorescence background. Orthogonal projections across 3D confocal stacks show that the nanocrystals are able to enter the cells positioning themselves within the cytoplasm. Overall, the new FAP-Pr nanocrystals are biocompatible and of the tested types, the 0.5% Pr3+ doped nanocrystals show the highest promise as a tracking nanoparticle probe for bioimaging applications.",
publisher = "Amsterdam : Elsevier",
journal = "Journal of Luminescence",
title = "Fabrication and characterization of luminescent Pr3+ doped fluorapatite nanocrystals as bioimaging contrast agents",
volume = "217",
doi = "10.1016/j.jlumin.2019.116757"
}

Milojkov, D. V., Silvestre, O. F., Stanic, V., Janjic, G. V., Mutavdžić, D., Milanović, M.,& Nieder, J. B.. (2020). Fabrication and characterization of luminescent Pr3+ doped fluorapatite nanocrystals as bioimaging contrast agents. in Journal of Luminescence
Amsterdam : Elsevier., 217.
https://doi.org/10.1016/j.jlumin.2019.116757

Milojkov DV, Silvestre OF, Stanic V, Janjic GV, Mutavdžić D, Milanović M, Nieder JB. Fabrication and characterization of luminescent Pr3+ doped fluorapatite nanocrystals as bioimaging contrast agents. in Journal of Luminescence. 2020;217.
doi:10.1016/j.jlumin.2019.116757 .

Milojkov, Dusan V., Silvestre, Oscar F., Stanic, Vojislav, Janjic, Goran V., Mutavdžić, Dragosav, Milanović, Marija, Nieder, Jana B., "Fabrication and characterization of luminescent Pr3+ doped fluorapatite nanocrystals as bioimaging contrast agents" in Journal of Luminescence, 217 (2020),
https://doi.org/10.1016/j.jlumin.2019.116757 . .

TY  - JOUR
AU  - Milojkov, D. V.
AU  - Stanic, Vojislav
AU  - Dimović, S. D.
AU  - Mutavdžić, Dragosav
AU  - Živkovic-Radovanović, V.
AU  - Janjic, Goran V.
AU  - Radotić, Ksenija
PY  - 2019
UR  - http://rimsi.imsi.bg.ac.rs/handle/123456789/1230
AB  - In the present study we have analyzed effects of Ag+ ions doping on energetic profiles of nanophosphors materials based on fluorapatite crystal system. The UV radiation absorption and luminescence properties of monophase fluorapatite (FAP) and Ag+ doped fluorapatite (AgFAP) nanomaterials obtained by neutralization method were investigated using the photoluminescence spectrophotometry. The excitation-emission profiles of nanomaterials were analyzed statistically by MCR-ALS method and number of fluorophores was extracted. FAP lattice absorbed light at 350 nm in the UVA part of spectrum, and with increasing concentration of Ag+ ions new absorption maximum appeared at 270 nm in the UVC part. Fluorescence of FAP nanoparticles was in violet region of visible part of the spectrum, with a red shift to the green region when Ag+ was doped in lattice. MCR-ALS analyses of fluorescence spectra confirm formation of two maxima, at 484 and 505 nm, as a consequence of Ag+ ions doping in FAP lattice at Cal (4f) sites. The results of quantum chemical calculations showed that an Ag+ ion is stronger bonded to the binding site 1 (-1352.6 kcal/mol) than to the binding site 2 (-1249.0 kcal/mol). Considering that AgFAP1 nanopowder absorbs photons over all part of UV radiation spectrum, this material might be used as potential radiation protective nanomaterial.
PB  - Polish Acad Sciences Inst Physics, Warsaw
T2  - Acta Physica Polonica A
T1  - Effects of Ag+ Ion Doping on UV Radiation Absorption and Luminescence Profiles of Fluorapatite Nanomaterials Obtained by Neutralization Method
EP  - 91
IS  - 1
SP  - 86
VL  - 136
DO  - 10.12693/APhysPolA.136.86
ER  - 

@article{
author = "Milojkov, D. V. and Stanic, Vojislav and Dimović, S. D. and Mutavdžić, Dragosav and Živkovic-Radovanović, V. and Janjic, Goran V. and Radotić, Ksenija",
year = "2019",
abstract = "In the present study we have analyzed effects of Ag+ ions doping on energetic profiles of nanophosphors materials based on fluorapatite crystal system. The UV radiation absorption and luminescence properties of monophase fluorapatite (FAP) and Ag+ doped fluorapatite (AgFAP) nanomaterials obtained by neutralization method were investigated using the photoluminescence spectrophotometry. The excitation-emission profiles of nanomaterials were analyzed statistically by MCR-ALS method and number of fluorophores was extracted. FAP lattice absorbed light at 350 nm in the UVA part of spectrum, and with increasing concentration of Ag+ ions new absorption maximum appeared at 270 nm in the UVC part. Fluorescence of FAP nanoparticles was in violet region of visible part of the spectrum, with a red shift to the green region when Ag+ was doped in lattice. MCR-ALS analyses of fluorescence spectra confirm formation of two maxima, at 484 and 505 nm, as a consequence of Ag+ ions doping in FAP lattice at Cal (4f) sites. The results of quantum chemical calculations showed that an Ag+ ion is stronger bonded to the binding site 1 (-1352.6 kcal/mol) than to the binding site 2 (-1249.0 kcal/mol). Considering that AgFAP1 nanopowder absorbs photons over all part of UV radiation spectrum, this material might be used as potential radiation protective nanomaterial.",
publisher = "Polish Acad Sciences Inst Physics, Warsaw",
journal = "Acta Physica Polonica A",
title = "Effects of Ag+ Ion Doping on UV Radiation Absorption and Luminescence Profiles of Fluorapatite Nanomaterials Obtained by Neutralization Method",
pages = "91-86",
number = "1",
volume = "136",
doi = "10.12693/APhysPolA.136.86"
}

Milojkov, D. V., Stanic, V., Dimović, S. D., Mutavdžić, D., Živkovic-Radovanović, V., Janjic, G. V.,& Radotić, K.. (2019). Effects of Ag+ Ion Doping on UV Radiation Absorption and Luminescence Profiles of Fluorapatite Nanomaterials Obtained by Neutralization Method. in Acta Physica Polonica A
Polish Acad Sciences Inst Physics, Warsaw., 136(1), 86-91.
https://doi.org/10.12693/APhysPolA.136.86

Milojkov DV, Stanic V, Dimović SD, Mutavdžić D, Živkovic-Radovanović V, Janjic GV, Radotić K. Effects of Ag+ Ion Doping on UV Radiation Absorption and Luminescence Profiles of Fluorapatite Nanomaterials Obtained by Neutralization Method. in Acta Physica Polonica A. 2019;136(1):86-91.
doi:10.12693/APhysPolA.136.86 .

Milojkov, D. V., Stanic, Vojislav, Dimović, S. D., Mutavdžić, Dragosav, Živkovic-Radovanović, V., Janjic, Goran V., Radotić, Ksenija, "Effects of Ag+ Ion Doping on UV Radiation Absorption and Luminescence Profiles of Fluorapatite Nanomaterials Obtained by Neutralization Method" in Acta Physica Polonica A, 136, no. 1 (2019):86-91,
https://doi.org/10.12693/APhysPolA.136.86 . .