TY  - JOUR
AU  - Jauković, Valentina
AU  - Krajišnik, Danina R.
AU  - Daković, Aleksandra S.
AU  - Damjanović, Ana B.
AU  - Krstić, Jugoslav
AU  - Stojanović, Jovica
AU  - Čalija, Bojan
PY  - 2021
UR  - https://cer.ihtm.bg.ac.rs/handle/123456789/4487
AB  - The functionality of halloysite (Hal) nanotubes as drug carriers can be improved by lumen enlargement and polymer modification. This study investigates the influence of selective acid etching on Hal functionalization with cationic biopolymer chitosan. Hal was subjected to lumen etching under mild conditions, loaded under vacuum with nonsteroidal antiinflammatory drug aceclofenac, and incubated in an acidic solution of chitosan. The functionality of pristine and etched Hal before and upon polymer functionalization was assessed by ζ-potential measurements, structural characterization (FT-IR, DSC and XRPD analysis), cell viability assay, drug loading and drug release studies. Acid etching increased specific surface area, pore volume and pore size of Hal, decreased ζ-potential and facilitated binding of the cationic polymer. XRPD and DSC analysis revealed crystalline structure of etched Hal. Successful chitosan binding and drug entrapment were further confirmed by FT-IR and DSC studies. XRPD showed surface polymer binding. DSC and FT-IR analyses confirmed the presence of the entrapped drug in its crystalline form. Drug loading was increased for ≈81% by selective lumen etching. Slight decrease of drug content occurred during chitosan functionalization due to aceclofenac diffusion in the polymer solution. The drug release was more sustained from etched Hal nanocomposites (up to ≈87% for 12 h) than from pristine Hal (up to ≈97% for 12 h) due to more intensive chitosan binding. High human fibroblast survival rates upon exposure to pristine and etched Hal before and after chitosan functionalization (>90% in the concentration of 1000 μg/mL) confirmed that both lumen etching under mild conditions and polymer functionalization had no significant effect on cytocompatibility. Based on these findings, selective lumen etching in combination with polycation modification appears to be a promising approach for improvement of Hal nanotubes functionality by increasing payload, polymer binding capacity, and sustained release properties with no significant effect on their cytocompatibility.
PB  - Elsevier
T2  - Materials Science and Engineering C
T1  - Influence of selective acid-etching on functionality of halloysite-chitosan nanocontainers for sustained drug release
VL  - 123
SP  - 112029
DO  - 10.1016/j.msec.2021.112029
ER  - 

@article{
author = "Jauković, Valentina and Krajišnik, Danina R. and Daković, Aleksandra S. and Damjanović, Ana B. and Krstić, Jugoslav and Stojanović, Jovica and Čalija, Bojan",
year = "2021",
abstract = "The functionality of halloysite (Hal) nanotubes as drug carriers can be improved by lumen enlargement and polymer modification. This study investigates the influence of selective acid etching on Hal functionalization with cationic biopolymer chitosan. Hal was subjected to lumen etching under mild conditions, loaded under vacuum with nonsteroidal antiinflammatory drug aceclofenac, and incubated in an acidic solution of chitosan. The functionality of pristine and etched Hal before and upon polymer functionalization was assessed by ζ-potential measurements, structural characterization (FT-IR, DSC and XRPD analysis), cell viability assay, drug loading and drug release studies. Acid etching increased specific surface area, pore volume and pore size of Hal, decreased ζ-potential and facilitated binding of the cationic polymer. XRPD and DSC analysis revealed crystalline structure of etched Hal. Successful chitosan binding and drug entrapment were further confirmed by FT-IR and DSC studies. XRPD showed surface polymer binding. DSC and FT-IR analyses confirmed the presence of the entrapped drug in its crystalline form. Drug loading was increased for ≈81% by selective lumen etching. Slight decrease of drug content occurred during chitosan functionalization due to aceclofenac diffusion in the polymer solution. The drug release was more sustained from etched Hal nanocomposites (up to ≈87% for 12 h) than from pristine Hal (up to ≈97% for 12 h) due to more intensive chitosan binding. High human fibroblast survival rates upon exposure to pristine and etched Hal before and after chitosan functionalization (>90% in the concentration of 1000 μg/mL) confirmed that both lumen etching under mild conditions and polymer functionalization had no significant effect on cytocompatibility. Based on these findings, selective lumen etching in combination with polycation modification appears to be a promising approach for improvement of Hal nanotubes functionality by increasing payload, polymer binding capacity, and sustained release properties with no significant effect on their cytocompatibility.",
publisher = "Elsevier",
journal = "Materials Science and Engineering C",
title = "Influence of selective acid-etching on functionality of halloysite-chitosan nanocontainers for sustained drug release",
volume = "123",
pages = "112029",
doi = "10.1016/j.msec.2021.112029"
}

Jauković, V., Krajišnik, D. R., Daković, A. S., Damjanović, A. B., Krstić, J., Stojanović, J.,& Čalija, B.. (2021). Influence of selective acid-etching on functionality of halloysite-chitosan nanocontainers for sustained drug release. in Materials Science and Engineering C
Elsevier., 123, 112029.
https://doi.org/10.1016/j.msec.2021.112029

Jauković V, Krajišnik DR, Daković AS, Damjanović AB, Krstić J, Stojanović J, Čalija B. Influence of selective acid-etching on functionality of halloysite-chitosan nanocontainers for sustained drug release. in Materials Science and Engineering C. 2021;123:112029.
doi:10.1016/j.msec.2021.112029 .

Jauković, Valentina, Krajišnik, Danina R., Daković, Aleksandra S., Damjanović, Ana B., Krstić, Jugoslav, Stojanović, Jovica, Čalija, Bojan, "Influence of selective acid-etching on functionality of halloysite-chitosan nanocontainers for sustained drug release" in Materials Science and Engineering C, 123 (2021):112029,
https://doi.org/10.1016/j.msec.2021.112029 . .

TY  - JOUR
AU  - Šoštarić, Tatjana
AU  - Petrović, Marija
AU  - Stojanović, Jovica
AU  - Marković, Marija
AU  - Avdalović, Jelena
AU  - Hosseini-Bandegharaei, Ahmad
AU  - Lopičić, Zorica
PY  - 2020
UR  - https://cer.ihtm.bg.ac.rs/handle/123456789/4036
AB  - A low-cost waste biomass generated from a food industry, apricot shells, was subjected to alkali modification in order to compare morphology, crystalline structure and thermal stability of native and modified biomass, accompanied by their cellulose-rich fractions. The surface morphology and structure of compared samples were analysed by the scanning electron microscopy (SEM) and mercury porosimetry. Furthermore, Fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD) and thermal analysis (TG/DTA) were applied. The results have shown that after alkaline treatment, inter- and intra-particle porosity in the material rises, resulting in increase of the total surface area. The XRD diffractograms showed that crystallinity index increased together with crystallite size, suggesting that modified sample has more ordered crystalline structure than native sample (also confirmed by the FTIR analysis). Although the cellulose-rich fraction extracted from the alkali-modified sample showed higher thermal stability, the overall thermal analysis revealed that alkali-modified biomass has lower thermal stability than the native sample. This indicates that this type of modification will improve the fuel properties of this lignocellulosic biomass and imply its possible application in energy recovery process.
PB  - Springer Science and Business Media LLC
T2  - Biomass Conversion and Biorefinery
T1  - Structural changes of waste biomass induced by alkaline treatment: the effect on crystallinity and thermal properties
DO  - 10.1007/s13399-020-00766-2
ER  - 

@article{
author = "Šoštarić, Tatjana and Petrović, Marija and Stojanović, Jovica and Marković, Marija and Avdalović, Jelena and Hosseini-Bandegharaei, Ahmad and Lopičić, Zorica",
year = "2020",
abstract = "A low-cost waste biomass generated from a food industry, apricot shells, was subjected to alkali modification in order to compare morphology, crystalline structure and thermal stability of native and modified biomass, accompanied by their cellulose-rich fractions. The surface morphology and structure of compared samples were analysed by the scanning electron microscopy (SEM) and mercury porosimetry. Furthermore, Fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD) and thermal analysis (TG/DTA) were applied. The results have shown that after alkaline treatment, inter- and intra-particle porosity in the material rises, resulting in increase of the total surface area. The XRD diffractograms showed that crystallinity index increased together with crystallite size, suggesting that modified sample has more ordered crystalline structure than native sample (also confirmed by the FTIR analysis). Although the cellulose-rich fraction extracted from the alkali-modified sample showed higher thermal stability, the overall thermal analysis revealed that alkali-modified biomass has lower thermal stability than the native sample. This indicates that this type of modification will improve the fuel properties of this lignocellulosic biomass and imply its possible application in energy recovery process.",
publisher = "Springer Science and Business Media LLC",
journal = "Biomass Conversion and Biorefinery",
title = "Structural changes of waste biomass induced by alkaline treatment: the effect on crystallinity and thermal properties",
doi = "10.1007/s13399-020-00766-2"
}

Šoštarić, T., Petrović, M., Stojanović, J., Marković, M., Avdalović, J., Hosseini-Bandegharaei, A.,& Lopičić, Z.. (2020). Structural changes of waste biomass induced by alkaline treatment: the effect on crystallinity and thermal properties. in Biomass Conversion and Biorefinery
Springer Science and Business Media LLC..
https://doi.org/10.1007/s13399-020-00766-2

Šoštarić T, Petrović M, Stojanović J, Marković M, Avdalović J, Hosseini-Bandegharaei A, Lopičić Z. Structural changes of waste biomass induced by alkaline treatment: the effect on crystallinity and thermal properties. in Biomass Conversion and Biorefinery. 2020;.
doi:10.1007/s13399-020-00766-2 .

Šoštarić, Tatjana, Petrović, Marija, Stojanović, Jovica, Marković, Marija, Avdalović, Jelena, Hosseini-Bandegharaei, Ahmad, Lopičić, Zorica, "Structural changes of waste biomass induced by alkaline treatment: the effect on crystallinity and thermal properties" in Biomass Conversion and Biorefinery (2020),
https://doi.org/10.1007/s13399-020-00766-2 . .

TY  - JOUR
AU  - Milićević, Sonja
AU  - Martinović, Sanja
AU  - Milošević, Vladan
AU  - Stojanović, Jovica
AU  - Povrenović, Dragan
PY  - 2018
UR  - https://cer.ihtm.bg.ac.rs/handle/123456789/2366
AB  - Systematic modification of three structurally different minerals (zeolite, mica, and vermiculite) was carried out with the aim of determining the modification mechanism and exposing the hydrophobic surface that can be used as a sorbent for many organic compounds. Mechanism of modification with cationic surfactant depends strongly on the mineral type. In order to identify the influence of aluminosilicates structural differences on the modification process, adsorption experiments with organic matter and water vapor, supplemented with the DTA/TG analysis, were performed. The cation exchange capacity (CEC) value was 1454>560>28meqkg(-1) for zeolite (clinoptilolite), vermiculite, and mica (muscovite), respectively. Despite its CEC value, vermiculite adsorbed three times the amount of organic matter than did clinoptilolite due to the porous structure of zeolite, which acted to limit the adsorption only on the external exchangeable cations. If the loading amount is equal to the CEC or the external cation exchange capacity for clinoptilolite (ECEC approximate to 10% CEC), the monolayer will form while mineral surface will have hydrophobic character. Only one active center exists at the surface of the clinoptilolite that was identified by DTA curves with a sharp and defined peak around 300 degrees C and by the mass loss at the TG diagrams. Two significant and equal active centers were observed in vermiculite, one for the exchange of the surface cations and the other for the interlayer cations and H2O molecules. Muscovite CEC is negligible, and due to the absence of any other functional groups, the modification of this mineral was impossible.
PB  - Springer
T2  - Journal of Thermal Analysis and Calorimetry
T1  - Differences in coating mechanism of structurally different aluminosilicates observed through the thermal analysis
VL  - 134
IS  - 2
SP  - 1011
EP  - 1019
DO  - 10.1007/s10973-018-7351-3
ER  - 

@article{
author = "Milićević, Sonja and Martinović, Sanja and Milošević, Vladan and Stojanović, Jovica and Povrenović, Dragan",
year = "2018",
abstract = "Systematic modification of three structurally different minerals (zeolite, mica, and vermiculite) was carried out with the aim of determining the modification mechanism and exposing the hydrophobic surface that can be used as a sorbent for many organic compounds. Mechanism of modification with cationic surfactant depends strongly on the mineral type. In order to identify the influence of aluminosilicates structural differences on the modification process, adsorption experiments with organic matter and water vapor, supplemented with the DTA/TG analysis, were performed. The cation exchange capacity (CEC) value was 1454>560>28meqkg(-1) for zeolite (clinoptilolite), vermiculite, and mica (muscovite), respectively. Despite its CEC value, vermiculite adsorbed three times the amount of organic matter than did clinoptilolite due to the porous structure of zeolite, which acted to limit the adsorption only on the external exchangeable cations. If the loading amount is equal to the CEC or the external cation exchange capacity for clinoptilolite (ECEC approximate to 10% CEC), the monolayer will form while mineral surface will have hydrophobic character. Only one active center exists at the surface of the clinoptilolite that was identified by DTA curves with a sharp and defined peak around 300 degrees C and by the mass loss at the TG diagrams. Two significant and equal active centers were observed in vermiculite, one for the exchange of the surface cations and the other for the interlayer cations and H2O molecules. Muscovite CEC is negligible, and due to the absence of any other functional groups, the modification of this mineral was impossible.",
publisher = "Springer",
journal = "Journal of Thermal Analysis and Calorimetry",
title = "Differences in coating mechanism of structurally different aluminosilicates observed through the thermal analysis",
volume = "134",
number = "2",
pages = "1011-1019",
doi = "10.1007/s10973-018-7351-3"
}

Milićević, S., Martinović, S., Milošević, V., Stojanović, J.,& Povrenović, D.. (2018). Differences in coating mechanism of structurally different aluminosilicates observed through the thermal analysis. in Journal of Thermal Analysis and Calorimetry
Springer., 134(2), 1011-1019.
https://doi.org/10.1007/s10973-018-7351-3

Milićević S, Martinović S, Milošević V, Stojanović J, Povrenović D. Differences in coating mechanism of structurally different aluminosilicates observed through the thermal analysis. in Journal of Thermal Analysis and Calorimetry. 2018;134(2):1011-1019.
doi:10.1007/s10973-018-7351-3 .

Milićević, Sonja, Martinović, Sanja, Milošević, Vladan, Stojanović, Jovica, Povrenović, Dragan, "Differences in coating mechanism of structurally different aluminosilicates observed through the thermal analysis" in Journal of Thermal Analysis and Calorimetry, 134, no. 2 (2018):1011-1019,
https://doi.org/10.1007/s10973-018-7351-3 . .

TY  - JOUR
AU  - Đošić, Marija
AU  - Eraković, Sanja
AU  - Janković, Ana
AU  - Vukašinović-Sekulić, Maja
AU  - Matić, Ivana Z.
AU  - Stojanović, Jovica
AU  - Rhee, Kyong Yop
AU  - Mišković-Stanković, Vesna
AU  - Park, Soo-Jin
PY  - 2017
UR  - http://TechnoRep.tmf.bg.ac.rs/handle/123456789/3703
UR  - https://cer.ihtm.bg.ac.rs/handle/123456789/6743
AB  - Graphene (Gr) and natural polymer chitosan (CS) were introduced to hydroxyapatite (HAP) to produce a three-component composite coating, which was fabricated by cathodic electrophoretic deposition on Ti substrates in an ethanol suspension. These HAP/CS/Gr coatings were characterized by X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FT-IR), thermogravimetric analysis (TGA), X-ray photoelectron spectroscopy (XPS) and electrochemical measurements and found that the graphene into HAP/CS composites significantly improves their morphology, thermal stability, and bioactivity. Both HAP/CS and HAP/CS/Gr composite coatings are classified as non-cytotoxic when tested against healthy peripheral blood mononuclear cells (PBMC), while antibacterial activity against Staphylococcus aureus and Escherichia coil could not be verified.
PB  - Elsevier
T2  - Journal of Industrial and Engineering Chemistry
T1  - In vitro investigation of electrophoretically deposited bioactive hydroxyapatite/chitosan coatings reinforced by graphene
VL  - 47
SP  - 336
EP  - 347
DO  - 10.1016/j.jiec.2016.12.004
ER  - 

@article{
author = "Đošić, Marija and Eraković, Sanja and Janković, Ana and Vukašinović-Sekulić, Maja and Matić, Ivana Z. and Stojanović, Jovica and Rhee, Kyong Yop and Mišković-Stanković, Vesna and Park, Soo-Jin",
year = "2017",
abstract = "Graphene (Gr) and natural polymer chitosan (CS) were introduced to hydroxyapatite (HAP) to produce a three-component composite coating, which was fabricated by cathodic electrophoretic deposition on Ti substrates in an ethanol suspension. These HAP/CS/Gr coatings were characterized by X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FT-IR), thermogravimetric analysis (TGA), X-ray photoelectron spectroscopy (XPS) and electrochemical measurements and found that the graphene into HAP/CS composites significantly improves their morphology, thermal stability, and bioactivity. Both HAP/CS and HAP/CS/Gr composite coatings are classified as non-cytotoxic when tested against healthy peripheral blood mononuclear cells (PBMC), while antibacterial activity against Staphylococcus aureus and Escherichia coil could not be verified.",
publisher = "Elsevier",
journal = "Journal of Industrial and Engineering Chemistry",
title = "In vitro investigation of electrophoretically deposited bioactive hydroxyapatite/chitosan coatings reinforced by graphene",
volume = "47",
pages = "336-347",
doi = "10.1016/j.jiec.2016.12.004"
}

Đošić, M., Eraković, S., Janković, A., Vukašinović-Sekulić, M., Matić, I. Z., Stojanović, J., Rhee, K. Y., Mišković-Stanković, V.,& Park, S.. (2017). In vitro investigation of electrophoretically deposited bioactive hydroxyapatite/chitosan coatings reinforced by graphene. in Journal of Industrial and Engineering Chemistry
Elsevier., 47, 336-347.
https://doi.org/10.1016/j.jiec.2016.12.004

Đošić M, Eraković S, Janković A, Vukašinović-Sekulić M, Matić IZ, Stojanović J, Rhee KY, Mišković-Stanković V, Park S. In vitro investigation of electrophoretically deposited bioactive hydroxyapatite/chitosan coatings reinforced by graphene. in Journal of Industrial and Engineering Chemistry. 2017;47:336-347.
doi:10.1016/j.jiec.2016.12.004 .

Đošić, Marija, Eraković, Sanja, Janković, Ana, Vukašinović-Sekulić, Maja, Matić, Ivana Z., Stojanović, Jovica, Rhee, Kyong Yop, Mišković-Stanković, Vesna, Park, Soo-Jin, "In vitro investigation of electrophoretically deposited bioactive hydroxyapatite/chitosan coatings reinforced by graphene" in Journal of Industrial and Engineering Chemistry, 47 (2017):336-347,
https://doi.org/10.1016/j.jiec.2016.12.004 . .

TY  - JOUR
AU  - Milićević, Sonja
AU  - Milošević, Vladan
AU  - Povrenović, Dragan
AU  - Stojanović, Jovica
AU  - Martinović, Sanja
AU  - Babić, Biljana
PY  - 2013
UR  - https://cer.ihtm.bg.ac.rs/handle/123456789/6897
AB  - The increasing levels of industrial wastewater released to the environment present a serious
threat to human health, living resources, and ecological systems. Fe-modified zeolites were developed and tested for removal of Cu2+ and Zn2+ from contaminated water. The surfaces of the naturally occurring zeolite, clinoptilolite, were modified with Fe(III) oxyhydroxides using three different methods, denoted I, II, and III (FeCli1 , FeCli2, and FeNaCli1, respectively). The oxyhydroxides were prepared in Method I using 0.1 M FeCl3 · H2O in an acetate buffer (pH = 3.6); in Method II, using 10% FeCl3 · H2O solution in 0.1 M KOH (pH = 10); and Method III was the same as Method I except the clinoptilolite was pretreated with NaCl. Newly synthesized materials from these three methods were then tested for their ability to enhance the sorption capacity for Cu and Zn compared to the natural sample (Cli). Powder X-ray diffraction measurements and the chemical composition of these modified samples confirmed that
clinoptilolite maintained its structure while amorphous Fe3+ species were synthesized. The specific surface area (BET method) of both the natural and modified clinoptilolite increased by 2 and 7.5 times for Methods I and II, respectively. Scanning electron microscopy and energy dispersive X-ray spectroscopy revealed that CaO was formed during Method I (FeCli1). Throughout the adsorption process, the hydrolysis of CaO and the release of OH¯ caused the precipitation of Cu and Zn hydroxide, which made the determination of the sorption capacity of FeCli1 impossible. This phenomenon was avoided in Method III (FeNaCli1) because of the absence of exchangeable Ca2+. The adsorption experiments with method II resulted in
double-enchanced adsoprtion capacity. Laboratory batch experiments have shown that the sorption capacities increased in the following order: Cli < FeCli2 < FeNaCli1, for Cu: 0.121 mmol/g < 0.251 mmol/g < 0.403 mmol/g and for Zn: 0.128 mmol/g < 0.234 mmol/g < 0.381 mmol/g.
PB  - Springer
T2  - Clay and Clay Minerals
T1  - Removal of heavy metals from aqueous solutions using natural and Fe(III) oxyhydroxide clinoptilolite
VL  - 61
VL  - 517
IS  - 6
SP  - 508
DO  - 10.1346/CCMN.2013.0610603
ER  - 

@article{
author = "Milićević, Sonja and Milošević, Vladan and Povrenović, Dragan and Stojanović, Jovica and Martinović, Sanja and Babić, Biljana",
year = "2013",
abstract = "The increasing levels of industrial wastewater released to the environment present a serious
threat to human health, living resources, and ecological systems. Fe-modified zeolites were developed and tested for removal of Cu2+ and Zn2+ from contaminated water. The surfaces of the naturally occurring zeolite, clinoptilolite, were modified with Fe(III) oxyhydroxides using three different methods, denoted I, II, and III (FeCli1 , FeCli2, and FeNaCli1, respectively). The oxyhydroxides were prepared in Method I using 0.1 M FeCl3 · H2O in an acetate buffer (pH = 3.6); in Method II, using 10% FeCl3 · H2O solution in 0.1 M KOH (pH = 10); and Method III was the same as Method I except the clinoptilolite was pretreated with NaCl. Newly synthesized materials from these three methods were then tested for their ability to enhance the sorption capacity for Cu and Zn compared to the natural sample (Cli). Powder X-ray diffraction measurements and the chemical composition of these modified samples confirmed that
clinoptilolite maintained its structure while amorphous Fe3+ species were synthesized. The specific surface area (BET method) of both the natural and modified clinoptilolite increased by 2 and 7.5 times for Methods I and II, respectively. Scanning electron microscopy and energy dispersive X-ray spectroscopy revealed that CaO was formed during Method I (FeCli1). Throughout the adsorption process, the hydrolysis of CaO and the release of OH¯ caused the precipitation of Cu and Zn hydroxide, which made the determination of the sorption capacity of FeCli1 impossible. This phenomenon was avoided in Method III (FeNaCli1) because of the absence of exchangeable Ca2+. The adsorption experiments with method II resulted in
double-enchanced adsoprtion capacity. Laboratory batch experiments have shown that the sorption capacities increased in the following order: Cli < FeCli2 < FeNaCli1, for Cu: 0.121 mmol/g < 0.251 mmol/g < 0.403 mmol/g and for Zn: 0.128 mmol/g < 0.234 mmol/g < 0.381 mmol/g.",
publisher = "Springer",
journal = "Clay and Clay Minerals",
title = "Removal of heavy metals from aqueous solutions using natural and Fe(III) oxyhydroxide clinoptilolite",
volume = "61, 517",
number = "6",
pages = "508",
doi = "10.1346/CCMN.2013.0610603"
}

Milićević, S., Milošević, V., Povrenović, D., Stojanović, J., Martinović, S.,& Babić, B.. (2013). Removal of heavy metals from aqueous solutions using natural and Fe(III) oxyhydroxide clinoptilolite. in Clay and Clay Minerals
Springer., 61(6), 508.
https://doi.org/10.1346/CCMN.2013.0610603

Milićević S, Milošević V, Povrenović D, Stojanović J, Martinović S, Babić B. Removal of heavy metals from aqueous solutions using natural and Fe(III) oxyhydroxide clinoptilolite. in Clay and Clay Minerals. 2013;61(6):508.
doi:10.1346/CCMN.2013.0610603 .

Milićević, Sonja, Milošević, Vladan, Povrenović, Dragan, Stojanović, Jovica, Martinović, Sanja, Babić, Biljana, "Removal of heavy metals from aqueous solutions using natural and Fe(III) oxyhydroxide clinoptilolite" in Clay and Clay Minerals, 61, no. 6 (2013):508,
https://doi.org/10.1346/CCMN.2013.0610603 . .