TY  - JOUR
AU  - Vukoje, Ivana
AU  - Lazić, Vesna M.
AU  - Sredojević, Dušan
AU  - Fernandes, Margarida M.
AU  - Lanceros-Mendez, Senentxu
AU  - Ahrenkiel, S. Phillip
AU  - Nedeljković, Jovan
PY  - 2022
UR  - https://vinar.vin.bg.ac.rs/handle/123456789/10052
AB  - Aqueous colloids, consisting of 15–30 nm-sized silver nanoparticles (Ag NPs), were prepared using the reducing and stabilizing abilities of glucose, sucrose, and dextran. The long-term stability of coated Ag NPs increases from glucose over sucrose to dextran, i.e., with the increase of the molecular weight of carbohydrate molecules. The density functional theory (DFT) calculations of the partial atomic (Mulliken) charges and adsorption energies are applied to explain the enhanced stability of coated Ag NPs. All coated Ag NPs have a significantly broader concentration range of nontoxic behavior toward pre-osteoblast cells than bare Ag NPs prepared using sodium borohydride. The carbohydrate-coated Ag NPs display the same level of toxic ability against Gram-negative (Escherichia coli) and Gram-positive (Staphylococcus aureus) bacteria as bare Ag NPs. The differences in toxicity mechanism of the coated and bare Ag NPs are a consequence of the absence and presence of co-occurring Ag+ ions in examined dispersion, respectively.
T2  - International Journal of Biological Macromolecules
T2  - International Journal of Biological MacromoleculesInternational Journal of Biological Macromolecules
T1  - Influence of glucose, sucrose, and dextran coatings on the stability and toxicity of silver nanoparticles
VL  - 194
SP  - 461
EP  - 469
DO  - 10.1016/j.ijbiomac.2021.11.089
ER  - 

@article{
author = "Vukoje, Ivana and Lazić, Vesna M. and Sredojević, Dušan and Fernandes, Margarida M. and Lanceros-Mendez, Senentxu and Ahrenkiel, S. Phillip and Nedeljković, Jovan",
year = "2022",
abstract = "Aqueous colloids, consisting of 15–30 nm-sized silver nanoparticles (Ag NPs), were prepared using the reducing and stabilizing abilities of glucose, sucrose, and dextran. The long-term stability of coated Ag NPs increases from glucose over sucrose to dextran, i.e., with the increase of the molecular weight of carbohydrate molecules. The density functional theory (DFT) calculations of the partial atomic (Mulliken) charges and adsorption energies are applied to explain the enhanced stability of coated Ag NPs. All coated Ag NPs have a significantly broader concentration range of nontoxic behavior toward pre-osteoblast cells than bare Ag NPs prepared using sodium borohydride. The carbohydrate-coated Ag NPs display the same level of toxic ability against Gram-negative (Escherichia coli) and Gram-positive (Staphylococcus aureus) bacteria as bare Ag NPs. The differences in toxicity mechanism of the coated and bare Ag NPs are a consequence of the absence and presence of co-occurring Ag+ ions in examined dispersion, respectively.",
journal = "International Journal of Biological Macromolecules, International Journal of Biological MacromoleculesInternational Journal of Biological Macromolecules",
title = "Influence of glucose, sucrose, and dextran coatings on the stability and toxicity of silver nanoparticles",
volume = "194",
pages = "461-469",
doi = "10.1016/j.ijbiomac.2021.11.089"
}

Vukoje, I., Lazić, V. M., Sredojević, D., Fernandes, M. M., Lanceros-Mendez, S., Ahrenkiel, S. P.,& Nedeljković, J.. (2022). Influence of glucose, sucrose, and dextran coatings on the stability and toxicity of silver nanoparticles. in International Journal of Biological Macromolecules, 194, 461-469.
https://doi.org/10.1016/j.ijbiomac.2021.11.089

Vukoje I, Lazić VM, Sredojević D, Fernandes MM, Lanceros-Mendez S, Ahrenkiel SP, Nedeljković J. Influence of glucose, sucrose, and dextran coatings on the stability and toxicity of silver nanoparticles. in International Journal of Biological Macromolecules. 2022;194:461-469.
doi:10.1016/j.ijbiomac.2021.11.089 .

Vukoje, Ivana, Lazić, Vesna M., Sredojević, Dušan, Fernandes, Margarida M., Lanceros-Mendez, Senentxu, Ahrenkiel, S. Phillip, Nedeljković, Jovan, "Influence of glucose, sucrose, and dextran coatings on the stability and toxicity of silver nanoparticles" in International Journal of Biological Macromolecules, 194 (2022):461-469,
https://doi.org/10.1016/j.ijbiomac.2021.11.089 . .

TY  - JOUR
AU  - Moreira, Joana
AU  - Fernandes, Margarida M.
AU  - Carvalho, Estela O.
AU  - Nicolau, Ana
AU  - Lazić, Vesna M.
AU  - Nedeljković, Jovan
AU  - Lanceros-Mendez, Senentxu
PY  - 2021
UR  - https://vinar.vin.bg.ac.rs/handle/123456789/9920
AB  - The search for alternative antimicrobial strategies capable of avoiding resistance mechanisms in bacteria are highly needed due to the alarming emergence of antimicrobial resistance. The application of physical stimuli as a mean of sensitizing bacteria for the action of antimicrobials on otherwise resistant bacteria or by allowing the action of low quantity of antimicrobials may be seen as a breakthrough for such purpose. This work proposes the development of antibacterial nanocomposites using the synergy between the electrically active microenvironments, created by a piezoelectric polymer (poly(vinylidene fluoride-co-trifluoroethylene) (PVDF-TrFE)), with green-synthesized silver nanoparticles (AgNPs). The electrical microenvironment is generated via mechanical stimulation of piezoelectric PVDF-TrFE/AgNPs films using a lab-made mechanical bioreactor. The generated material's electrical response further translates to bacterial cells, namely Escherichia coli and Staphylococcus epidermidis which in combination with AgNPs and the specific morphological features of the material induce important antibacterial and antibiofilm activity. Both porous and non-porous PVDF composites have shown antibacterial characteristics when stimulated at a mechanical frequency of 4 Hz being the effect boosted when AgNPs were incorporated in the nanocomposite, reducing in more than 80% the S. epidermidis bacterial growth in planktonic and biofilm form. The electroactive environments sensitize the bacteria allowing the action of a low dose of AgNPs (1.69% (w/w)). Importantly, the material did not compromise the viability of mammalian cells, thus being considered biocompatible. The piezoelectric stimulation of PVDF-based polymeric films may represent a breakthrough in the development of antibacterial coatings for devices used at hospital setting, taking advantage on the use of mechanical stimuli (pressure/touch) to exert antibacterial and antibiofilm activity.Statement of significanceThe application of physical methods in alternative to the common chemical ones is seen as a breakthrough for avoiding the emergence of antimicrobial resistance. Antimicrobial strategies that take advantage on the capability of bacteria to sense physical stimuli such as mechanical and electrical cues are scarce. Electroactive nanocomposites comprised of poly(vinylidene fluoride-co-trifluoroethylene (PVDF-TrFE) and green-synthesized silver nanoparticles (AgNPs) were developed to obtain material able to inhibit the colonization of microorganisms. By applying a mechanical stimuli to the nanocomposite, which ultimately mimics movements such as walking or touching, an antimicrobial effect is obtained, resulting from the synergy between the electroactive microenvironments created on the surface of the material and the AgNPs. Such environments sensitize the bacteria to low doses of antimicrobials.
T2  - Acta Biomaterialia
T1  - Exploring electroactive microenvironments in polymer-based nanocomposites to sensitize bacterial cells to low-dose embedded silver nanoparticles
DO  - 10.1016/j.actbio.2021.07.067
ER  - 

@article{
author = "Moreira, Joana and Fernandes, Margarida M. and Carvalho, Estela O. and Nicolau, Ana and Lazić, Vesna M. and Nedeljković, Jovan and Lanceros-Mendez, Senentxu",
year = "2021",
abstract = "The search for alternative antimicrobial strategies capable of avoiding resistance mechanisms in bacteria are highly needed due to the alarming emergence of antimicrobial resistance. The application of physical stimuli as a mean of sensitizing bacteria for the action of antimicrobials on otherwise resistant bacteria or by allowing the action of low quantity of antimicrobials may be seen as a breakthrough for such purpose. This work proposes the development of antibacterial nanocomposites using the synergy between the electrically active microenvironments, created by a piezoelectric polymer (poly(vinylidene fluoride-co-trifluoroethylene) (PVDF-TrFE)), with green-synthesized silver nanoparticles (AgNPs). The electrical microenvironment is generated via mechanical stimulation of piezoelectric PVDF-TrFE/AgNPs films using a lab-made mechanical bioreactor. The generated material's electrical response further translates to bacterial cells, namely Escherichia coli and Staphylococcus epidermidis which in combination with AgNPs and the specific morphological features of the material induce important antibacterial and antibiofilm activity. Both porous and non-porous PVDF composites have shown antibacterial characteristics when stimulated at a mechanical frequency of 4 Hz being the effect boosted when AgNPs were incorporated in the nanocomposite, reducing in more than 80% the S. epidermidis bacterial growth in planktonic and biofilm form. The electroactive environments sensitize the bacteria allowing the action of a low dose of AgNPs (1.69% (w/w)). Importantly, the material did not compromise the viability of mammalian cells, thus being considered biocompatible. The piezoelectric stimulation of PVDF-based polymeric films may represent a breakthrough in the development of antibacterial coatings for devices used at hospital setting, taking advantage on the use of mechanical stimuli (pressure/touch) to exert antibacterial and antibiofilm activity.Statement of significanceThe application of physical methods in alternative to the common chemical ones is seen as a breakthrough for avoiding the emergence of antimicrobial resistance. Antimicrobial strategies that take advantage on the capability of bacteria to sense physical stimuli such as mechanical and electrical cues are scarce. Electroactive nanocomposites comprised of poly(vinylidene fluoride-co-trifluoroethylene (PVDF-TrFE) and green-synthesized silver nanoparticles (AgNPs) were developed to obtain material able to inhibit the colonization of microorganisms. By applying a mechanical stimuli to the nanocomposite, which ultimately mimics movements such as walking or touching, an antimicrobial effect is obtained, resulting from the synergy between the electroactive microenvironments created on the surface of the material and the AgNPs. Such environments sensitize the bacteria to low doses of antimicrobials.",
journal = "Acta Biomaterialia",
title = "Exploring electroactive microenvironments in polymer-based nanocomposites to sensitize bacterial cells to low-dose embedded silver nanoparticles",
doi = "10.1016/j.actbio.2021.07.067"
}

Moreira, J., Fernandes, M. M., Carvalho, E. O., Nicolau, A., Lazić, V. M., Nedeljković, J.,& Lanceros-Mendez, S.. (2021). Exploring electroactive microenvironments in polymer-based nanocomposites to sensitize bacterial cells to low-dose embedded silver nanoparticles. in Acta Biomaterialia.
https://doi.org/10.1016/j.actbio.2021.07.067

Moreira J, Fernandes MM, Carvalho EO, Nicolau A, Lazić VM, Nedeljković J, Lanceros-Mendez S. Exploring electroactive microenvironments in polymer-based nanocomposites to sensitize bacterial cells to low-dose embedded silver nanoparticles. in Acta Biomaterialia. 2021;.
doi:10.1016/j.actbio.2021.07.067 .

Moreira, Joana, Fernandes, Margarida M., Carvalho, Estela O., Nicolau, Ana, Lazić, Vesna M., Nedeljković, Jovan, Lanceros-Mendez, Senentxu, "Exploring electroactive microenvironments in polymer-based nanocomposites to sensitize bacterial cells to low-dose embedded silver nanoparticles" in Acta Biomaterialia (2021),
https://doi.org/10.1016/j.actbio.2021.07.067 . .

TY  - JOUR
AU  - Lazić, Vesna M.
AU  - Živković, Ljiljana
AU  - Sredojević, Dušan
AU  - Fernandes,  Margarida M.
AU  - Lanceros-Mendez,  Senentxu
AU  - Ahrenkiel, Scott Phillip
AU  - Nedeljković, Jovan
PY  - 2020
UR  - https://vinar.vin.bg.ac.rs/handle/123456789/9613
AB  - Cerium dioxide (CeO2) finds applications in areas such as corrosion protection, solar cells, or catalysis, finding increasing applications in biomedicine. This work reports on surface-modified CeO2 particles in order to tune their applicability in the biomedical field. Stable aqueous CeO2 sol, consisting of 3-4 nm in size crystallites, was synthesized using forced hydrolysis. The coordination of catecholate-type of ligands (catechol, caffeic acid, tiron, and dopamine) to the surface-Ce atoms is followed with the appearance of absorption in the visible spectral range as a consequence of interfacial charge-transfer complex formation. The spectroscopic observations are complemented with the density functional theory calculations using a cluster model. The synthesized samples were characterized by X-ray diffraction analysis, transmission electron microscopy, and nitrogen adsorption-desorption isotherms. The ζ-potential measurements indicated that the stability of CeO2 sol is preserved upon surface modification. The pristine CeO2 nanoparticles (NPs) are nontoxic against pre-osteoblast cells in the entire studied concentration range (up to 1.5 mM). Hybrid CeO2 NPs, capped with dopamine or caffeic acid, display toxic behavior for concentrations ≥0.17 and 1.5 mM, respectively. On the other hand, surface-modified CeO2 NPs with catechol and tiron promote the proliferation of pre-osteoblast cells. Copyright © 2020 American Chemical Society.
T2  - Langmuir
T1  - Tuning properties of cerium dioxide nanoparticles by surface modification with catecholate-type of ligands
VL  - 36
IS  - 33
SP  - 9738
EP  - 9746
DO  - 10.1021/acs.langmuir.0c01163
ER  - 

@article{
author = "Lazić, Vesna M. and Živković, Ljiljana and Sredojević, Dušan and Fernandes,  Margarida M. and Lanceros-Mendez,  Senentxu and Ahrenkiel, Scott Phillip and Nedeljković, Jovan",
year = "2020",
abstract = "Cerium dioxide (CeO2) finds applications in areas such as corrosion protection, solar cells, or catalysis, finding increasing applications in biomedicine. This work reports on surface-modified CeO2 particles in order to tune their applicability in the biomedical field. Stable aqueous CeO2 sol, consisting of 3-4 nm in size crystallites, was synthesized using forced hydrolysis. The coordination of catecholate-type of ligands (catechol, caffeic acid, tiron, and dopamine) to the surface-Ce atoms is followed with the appearance of absorption in the visible spectral range as a consequence of interfacial charge-transfer complex formation. The spectroscopic observations are complemented with the density functional theory calculations using a cluster model. The synthesized samples were characterized by X-ray diffraction analysis, transmission electron microscopy, and nitrogen adsorption-desorption isotherms. The ζ-potential measurements indicated that the stability of CeO2 sol is preserved upon surface modification. The pristine CeO2 nanoparticles (NPs) are nontoxic against pre-osteoblast cells in the entire studied concentration range (up to 1.5 mM). Hybrid CeO2 NPs, capped with dopamine or caffeic acid, display toxic behavior for concentrations ≥0.17 and 1.5 mM, respectively. On the other hand, surface-modified CeO2 NPs with catechol and tiron promote the proliferation of pre-osteoblast cells. Copyright © 2020 American Chemical Society.",
journal = "Langmuir",
title = "Tuning properties of cerium dioxide nanoparticles by surface modification with catecholate-type of ligands",
volume = "36",
number = "33",
pages = "9738-9746",
doi = "10.1021/acs.langmuir.0c01163"
}

Lazić, V. M., Živković, L., Sredojević, D., Fernandes, M. M., Lanceros-Mendez, S., Ahrenkiel, S. P.,& Nedeljković, J.. (2020). Tuning properties of cerium dioxide nanoparticles by surface modification with catecholate-type of ligands. in Langmuir, 36(33), 9738-9746.
https://doi.org/10.1021/acs.langmuir.0c01163

Lazić VM, Živković L, Sredojević D, Fernandes MM, Lanceros-Mendez S, Ahrenkiel SP, Nedeljković J. Tuning properties of cerium dioxide nanoparticles by surface modification with catecholate-type of ligands. in Langmuir. 2020;36(33):9738-9746.
doi:10.1021/acs.langmuir.0c01163 .

Lazić, Vesna M., Živković, Ljiljana, Sredojević, Dušan, Fernandes,  Margarida M., Lanceros-Mendez,  Senentxu, Ahrenkiel, Scott Phillip, Nedeljković, Jovan, "Tuning properties of cerium dioxide nanoparticles by surface modification with catecholate-type of ligands" in Langmuir, 36, no. 33 (2020):9738-9746,
https://doi.org/10.1021/acs.langmuir.0c01163 . .