TY  - CONF
AU  - Dimitrijević, Jelena
AU  - Petrović, Jelena
AU  - Simić, Marija
AU  - Dikić, Jelena
AU  - Jevtić, Sanja
PY  - 2022
UR  - https://ritnms.itnms.ac.rs/handle/123456789/830
AB  - Zeolites are inorganic, crystalline aluminosilicates that nowadays has been used as
adsorbents, catalysts and carriers of catalytically activated substances, due to the small size
of their pores, large internal surface, and well-defined chemical composition. In this paper,
the modification of beta zeolite using (3-aminopropyl)-triethoxysilane (APTES) was
investigated. The results of the Fourier transform infrared spectroscopy and
thermogravimetric analysis confirmed the presence of amino groups derived from APTES
onto the modified zeolite surface. APTES-enriched zeolite was further used as an adsorbent
of silver ions from aqueous solutions. The obtained results reveal that a zeolite after
modification exhibited significantly better adsorption efficiency (97%) in comparison to the
unmodified (37%). The kinetic data follows the pseudo-second-order model which
indicates a chemical interaction between silver ions and functional amino groups on the
surface of the silanizedbeta zeolite. Ag-APTES enriched beta zeolite also was studied as
anantibacterial agent toward the pathogenic bacteria Gram-negative Escherichia coliDSM
498 and Gram-positive Staphylococcus aureus ATCC 25923.
C3  - YOUng researcheRS conference 2022
T1  - Antibacterial activity of amine-functionalized silver-enriched beta zeolite
EP  - 14
SP  - 14
ER  - 

@conference{
author = "Dimitrijević, Jelena and Petrović, Jelena and Simić, Marija and Dikić, Jelena and Jevtić, Sanja",
year = "2022",
abstract = "Zeolites are inorganic, crystalline aluminosilicates that nowadays has been used as
adsorbents, catalysts and carriers of catalytically activated substances, due to the small size
of their pores, large internal surface, and well-defined chemical composition. In this paper,
the modification of beta zeolite using (3-aminopropyl)-triethoxysilane (APTES) was
investigated. The results of the Fourier transform infrared spectroscopy and
thermogravimetric analysis confirmed the presence of amino groups derived from APTES
onto the modified zeolite surface. APTES-enriched zeolite was further used as an adsorbent
of silver ions from aqueous solutions. The obtained results reveal that a zeolite after
modification exhibited significantly better adsorption efficiency (97%) in comparison to the
unmodified (37%). The kinetic data follows the pseudo-second-order model which
indicates a chemical interaction between silver ions and functional amino groups on the
surface of the silanizedbeta zeolite. Ag-APTES enriched beta zeolite also was studied as
anantibacterial agent toward the pathogenic bacteria Gram-negative Escherichia coliDSM
498 and Gram-positive Staphylococcus aureus ATCC 25923.",
journal = "YOUng researcheRS conference 2022",
title = "Antibacterial activity of amine-functionalized silver-enriched beta zeolite",
pages = "14-14"
}

Dimitrijević, J., Petrović, J., Simić, M., Dikić, J.,& Jevtić, S.. (2022). Antibacterial activity of amine-functionalized silver-enriched beta zeolite. in YOUng researcheRS conference 2022, 14-14.

Dimitrijević J, Petrović J, Simić M, Dikić J, Jevtić S. Antibacterial activity of amine-functionalized silver-enriched beta zeolite. in YOUng researcheRS conference 2022. 2022;:14-14..

Dimitrijević, Jelena, Petrović, Jelena, Simić, Marija, Dikić, Jelena, Jevtić, Sanja, "Antibacterial activity of amine-functionalized silver-enriched beta zeolite" in YOUng researcheRS conference 2022 (2022):14-14.

TY  - CONF
AU  - Jevtić, Sanja
AU  - Dimitrijević, Jelena
AU  - Petrović, Jelena
AU  - Dikić, Jelena
PY  - 2022
UR  - https://ritnms.itnms.ac.rs/handle/123456789/860
AB  - Natural zeolite-clinoptilolite (from Vranjska Banja deposit in Serbia) and synthetic Beta zeolite,
were amin-functionalized using (3-aminopropyl)-triethoxysilane (APTES). The results of the
Fourier transform infrared spectroscopy and thermogravimetric analysis confirmed the presence of
amino groups derived from APTES onto the modified zeolite surface. APTES-enriched zeolite was
further used as an adsorbent of silver ions from aqueous solutions. Natural zeolite-clinoptilolite
showed a higher adsorption capacity (96 mg Ag/g), compared to beta zeolite (54 mg Ag/g) which is
attributed to the presence of exchangeable cations in the structure of clinoptilolite. The kinetic data
follows the pseudo-second-order model which indicates a chemical interaction between silver ions
and functional amino groups on the surface of the zeolite. Ag-APTES and APTES-enriched zeolites
further were studied as antibacterial agents toward the pathogenic bacteria Gram-negative
Escherichia coli DSM 498 and Gram-positive Staphylococcus aureus ATCC 25923. Based on the

results, it was concluded that the APTES-zeolites do not exhibit antibacterial activity while Ag-
APTES enriched zeolites shows antibacterial effect toward both examined bacterial strains.

Antibacterial activity is attributed to the presence of silver ions.
PB  - Banja Luka : University in Banja Luka, Faculty of Technology
C3  - XIV CONFERENCE OF CHEMISTS, TECHNOLOGISTS AND ENVIRONMENTALISTS OF REPUBLIC OF SRPSKA
T1  - Antibacterial activity of surface amine-functionalized silver-enriched zeolite
EP  - 178
SP  - 178
ER  - 

@conference{
author = "Jevtić, Sanja and Dimitrijević, Jelena and Petrović, Jelena and Dikić, Jelena",
year = "2022",
abstract = "Natural zeolite-clinoptilolite (from Vranjska Banja deposit in Serbia) and synthetic Beta zeolite,
were amin-functionalized using (3-aminopropyl)-triethoxysilane (APTES). The results of the
Fourier transform infrared spectroscopy and thermogravimetric analysis confirmed the presence of
amino groups derived from APTES onto the modified zeolite surface. APTES-enriched zeolite was
further used as an adsorbent of silver ions from aqueous solutions. Natural zeolite-clinoptilolite
showed a higher adsorption capacity (96 mg Ag/g), compared to beta zeolite (54 mg Ag/g) which is
attributed to the presence of exchangeable cations in the structure of clinoptilolite. The kinetic data
follows the pseudo-second-order model which indicates a chemical interaction between silver ions
and functional amino groups on the surface of the zeolite. Ag-APTES and APTES-enriched zeolites
further were studied as antibacterial agents toward the pathogenic bacteria Gram-negative
Escherichia coli DSM 498 and Gram-positive Staphylococcus aureus ATCC 25923. Based on the

results, it was concluded that the APTES-zeolites do not exhibit antibacterial activity while Ag-
APTES enriched zeolites shows antibacterial effect toward both examined bacterial strains.

Antibacterial activity is attributed to the presence of silver ions.",
publisher = "Banja Luka : University in Banja Luka, Faculty of Technology",
journal = "XIV CONFERENCE OF CHEMISTS, TECHNOLOGISTS AND ENVIRONMENTALISTS OF REPUBLIC OF SRPSKA",
title = "Antibacterial activity of surface amine-functionalized silver-enriched zeolite",
pages = "178-178"
}

Jevtić, S., Dimitrijević, J., Petrović, J.,& Dikić, J.. (2022). Antibacterial activity of surface amine-functionalized silver-enriched zeolite. in XIV CONFERENCE OF CHEMISTS, TECHNOLOGISTS AND ENVIRONMENTALISTS OF REPUBLIC OF SRPSKA
Banja Luka : University in Banja Luka, Faculty of Technology., 178-178.

Jevtić S, Dimitrijević J, Petrović J, Dikić J. Antibacterial activity of surface amine-functionalized silver-enriched zeolite. in XIV CONFERENCE OF CHEMISTS, TECHNOLOGISTS AND ENVIRONMENTALISTS OF REPUBLIC OF SRPSKA. 2022;:178-178..

Jevtić, Sanja, Dimitrijević, Jelena, Petrović, Jelena, Dikić, Jelena, "Antibacterial activity of surface amine-functionalized silver-enriched zeolite" in XIV CONFERENCE OF CHEMISTS, TECHNOLOGISTS AND ENVIRONMENTALISTS OF REPUBLIC OF SRPSKA (2022):178-178.

TY  - CONF
AU  - Sokić, Katarina
AU  - Veljović, Đorđe
AU  - Dikić, Jelena
AU  - Stojanović, Jovica
AU  - Smiljanić, Danijela
AU  - Jevtić, Sanja
PY  - 2021
UR  - https://ritnms.itnms.ac.rs/handle/123456789/728
AB  - The aim of this study was to investigate the possibilities and to optimize the conditions for the synthesis of hydroxyapatite (HAP) on calcium-enriched natural and synthetic zeolites as carriers. Two synthetic zeolites were used in the paper: zeolite 4A (Na-form) and zeolite 5A (Ca-form) as well as natural zeolite - clinoptilolite from Slanci deposit in Serbia.
Clinoptilolite and zeolite 4A were enriched with calcium ions by ion exchange treatmentin order to enable the source of Ca2+in the crystallization of hydroxyapatite. Phosphorus, necessary for the crystallization of hydroxyapatite, was introduced through a solution of ammonium-hydrogenphosphate. The influence of the concentration of hydrogen phosphate ions, temperature and crystallization time of hydroxyapatite on the morphology of the zeolite surface as well as the degree of its coverage with newly formed hydroxyapatite particles was monitored in the experiments. The obtained powders were characterized by X-ray powder diffraction (XRD), thermal TG-DTG analysis, infrared spectroscopy with Fourier transformation (FTIR) and scanning electron microscopy (SEM). Based on the structural analysis, it was shown that the synthesis of hydroxyapatite did not affect on the structure of the zeolite, except in the case when a very concentrated hydrogen-phosphate solution was used. Thermal analysis showed that all obtained zeolite and HAP samples were stable up to 800 °C. Optimization of the hydrothermal crystallization process showed that temperature and time do not have a crucial influence on the synthesis of the materials (similar results were obtained at 120 °C for 20 hours and at 160 °C for 4 hours). When the concentration of the solution of ammonium hydrogen phosphate was higher, larger crystals of hydroxyapatite were obtained, but the crystal lattice of the zeolite was collapsed. SEM micrography showed that unevenly distributed hydroxyapatite crystals were formed on natural zeolite due to the presence of various impurities, while the best results were achieved using zeolite 5A, where
the surface of the zeolite is completely covered with crystals of hydroxyapatite.
PB  - Belgrade : Institute of Technical Sciences of SASA
C3  - Nineteenth Young Researchers’ Conference - Materials Science and Engineering
T1  - Hydrothermal synthesis of hydroxyapatite on calcium-enriched natural and synthetic zeolite as a carrier
EP  - 75
SP  - 75
ER  - 

@conference{
author = "Sokić, Katarina and Veljović, Đorđe and Dikić, Jelena and Stojanović, Jovica and Smiljanić, Danijela and Jevtić, Sanja",
year = "2021",
abstract = "The aim of this study was to investigate the possibilities and to optimize the conditions for the synthesis of hydroxyapatite (HAP) on calcium-enriched natural and synthetic zeolites as carriers. Two synthetic zeolites were used in the paper: zeolite 4A (Na-form) and zeolite 5A (Ca-form) as well as natural zeolite - clinoptilolite from Slanci deposit in Serbia.
Clinoptilolite and zeolite 4A were enriched with calcium ions by ion exchange treatmentin order to enable the source of Ca2+in the crystallization of hydroxyapatite. Phosphorus, necessary for the crystallization of hydroxyapatite, was introduced through a solution of ammonium-hydrogenphosphate. The influence of the concentration of hydrogen phosphate ions, temperature and crystallization time of hydroxyapatite on the morphology of the zeolite surface as well as the degree of its coverage with newly formed hydroxyapatite particles was monitored in the experiments. The obtained powders were characterized by X-ray powder diffraction (XRD), thermal TG-DTG analysis, infrared spectroscopy with Fourier transformation (FTIR) and scanning electron microscopy (SEM). Based on the structural analysis, it was shown that the synthesis of hydroxyapatite did not affect on the structure of the zeolite, except in the case when a very concentrated hydrogen-phosphate solution was used. Thermal analysis showed that all obtained zeolite and HAP samples were stable up to 800 °C. Optimization of the hydrothermal crystallization process showed that temperature and time do not have a crucial influence on the synthesis of the materials (similar results were obtained at 120 °C for 20 hours and at 160 °C for 4 hours). When the concentration of the solution of ammonium hydrogen phosphate was higher, larger crystals of hydroxyapatite were obtained, but the crystal lattice of the zeolite was collapsed. SEM micrography showed that unevenly distributed hydroxyapatite crystals were formed on natural zeolite due to the presence of various impurities, while the best results were achieved using zeolite 5A, where
the surface of the zeolite is completely covered with crystals of hydroxyapatite.",
publisher = "Belgrade : Institute of Technical Sciences of SASA",
journal = "Nineteenth Young Researchers’ Conference - Materials Science and Engineering",
title = "Hydrothermal synthesis of hydroxyapatite on calcium-enriched natural and synthetic zeolite as a carrier",
pages = "75-75"
}

Sokić, K., Veljović, Đ., Dikić, J., Stojanović, J., Smiljanić, D.,& Jevtić, S.. (2021). Hydrothermal synthesis of hydroxyapatite on calcium-enriched natural and synthetic zeolite as a carrier. in Nineteenth Young Researchers’ Conference - Materials Science and Engineering
Belgrade : Institute of Technical Sciences of SASA., 75-75.

Sokić K, Veljović Đ, Dikić J, Stojanović J, Smiljanić D, Jevtić S. Hydrothermal synthesis of hydroxyapatite on calcium-enriched natural and synthetic zeolite as a carrier. in Nineteenth Young Researchers’ Conference - Materials Science and Engineering. 2021;:75-75..

Sokić, Katarina, Veljović, Đorđe, Dikić, Jelena, Stojanović, Jovica, Smiljanić, Danijela, Jevtić, Sanja, "Hydrothermal synthesis of hydroxyapatite on calcium-enriched natural and synthetic zeolite as a carrier" in Nineteenth Young Researchers’ Conference - Materials Science and Engineering (2021):75-75.