Violeta Dediu

@imt.ro

Research Centre for Integration of Technologies
National Institute for Research and Development in Microtechnologies -IMT Bucharest

Violeta Dediu


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https://researchid.co/violetadediu

RESEARCH, TEACHING, or OTHER INTERESTS

Materials Science, Colloid and Surface Chemistry, Biomaterials, Environmental Chemistry
21

Scopus Publications

398

Scholar Citations

9

Scholar h-index

9

Scholar i10-index

Scopus Publications

  • Cellulose–Silver and Cellulose–Gold Bioactive Nanocomposites Obtained Using SCOBY Purified Membranes
    Violeta Dediu, Mariana Buşilă, Claudia Ungureanu, Leontina Grigore-Gurgu, Mihaela Cotârleṭ, et al.
    ACS Applied Bio Materials, 2025
  • Thermally Induced Polymorphic Changes in Poly(vinylidene Fluoride) Thin Layer Investigated Using Micro-Raman Spectroscopy
    Munizer Purica, Florin Constantin Comanescu, Violeta Dediu
    Coatings, 2024
    Poly vinylidene fluoride (PVDF) is a versatile polymer that shows polymorphism, and most of its applications are based on its piezoelectric properties given by its polar crystalline phases. Increasing the polymer’s polar β-phase content has been a major pursuit in material science. We present the results on the evolution of induced polymorphic changes of PVDF through thermal treatment and the presence of the nano-ZnO with different morphologies. Three types of samples—a PVDF pure layer, PVDF:ZnO nanoparticles (NPs) and PVDF:ZnO nanorods (NRs)—were subjected to stress by heating at different temperatures from 50 °C close to melting temperature, 170 °C. The changes in PVDF–ZnO composite layers were investigated in situ using an experimental setup consisting of a high-resolution micro-Raman spectrometer and a thermo-electric cell. The ZnO NPs and NRs added in PVDF lead to obtaining a PVDF nanocomposite in which the intensity of the β phase is much higher than that of the α phase: intensities ratio Iβ(840.6 cm−1)/Iα(798.9 cm−1) > 5.56. The phase is stable up to 150 °C, and with the increase in temperature to 170 °C, the β phase passes to a lower crystallinity α phase with a large amorphous content highlighted by the 400–700 cm−1 and 800–1000 cm−1 regions without Raman peaks.
  • Thermally Induced Polymorphic Changes in Poly(Vinylidene Fluoride) Thin Layer Investigated Using Micro-Raman Spectroscopy
    Munizer Purica, Violeta Dediu, Florin Comanescu
    Proceedings of the International Semiconductor Conference CAS, 2024
  • Pressure Mapping System at the Level of the Sole of the Foot
    Florian Pistritu, Cătălin Pârvulescu, Marin Gheorghe, Violeta Dediu, Octavian Narcis Ionescu, et al.
    Proceedings of the International Semiconductor Conference CAS, 2024
  • Antibacterial and Photocatalytic Activity of ZnO/Au and ZnO/Ag Nanocomposites
    Mariana Busila, Viorica Musat, Petrica Alexandru, Cosmin Romanitan, Oana Brincoveanu, et al.
    International Journal of Molecular Sciences, 2023
    The use of a combination of nanoparticles as antimicrobial agents can be one strategy to overcome the tendency of microbes to become resistant to antibiotic action. Also, the optimization of nano-photocatalysts to efficiently remove persistent pollutants from wastewater is a hot topic. In this study, two composites ZnO/Au (1% wt.) and ZnO/Ag (1% wt.) were synthesized by simple aqueous solution methods. The structure and morphology of the r nanocomposites were analyzed by structural and optical characterization methods. The formation of AuNPs and AgNPs in these experiments was also discussed. The antimicrobial properties of ZnO, ZnO/Au, and ZnO/Ag nanomaterials were investigated against Gram-negative bacteria (Pseudomonas aeruginosa) and Gram-positive bacteria (Staphylococcus aureus). The results showed an increase of 80% in the antimicrobial activity of ZnO/Au against Pseudomonas aeruginosa compared with 30% in the case of ZnO/Ag. Similarly, in the case of the S. aureus strain tests, ZnO/Au increased the antimicrobial activity by 55% and ZnO/Ag by 33%. The photocatalytic tests indicated an improvement in the photocatalytic degradation of methylene blue (MB) under UV irradiation using ZnO/Au and ZnO/Ag nanocomposites compared to bare ZnO. The photocatalytic degradation efficiency of ZnO after 60 min of UV irradiation was ∼83%, while the addition of AuNPs enhanced the degradation rate to ∼95% (ZP2), and AgNP presence enhanced the efficiency to ∼98%. The introduction of noble metallic nanoparticles into the ZnO matrix proved to be an effective strategy to increase their antimicrobial activity against P. aeruginosa and S. aureus, and their photocatalytic activity was evaluated through the degradation of MB dye. Comparing the enhancing effects of Au and Ag, it was found that ZnO/Au was a better antimicrobial agent while ZnO/Ag was a more effective photocatalyst under UV irradiation.
  • Trends in Photothermal Nanostructures for Antimicrobial Applications
    Violeta Dediu, Jana Ghitman, Gratiela Gradisteanu Pircalabioru, Kiat Hwa Chan, Florina Silvia Iliescu, et al.
    International Journal of Molecular Sciences, 2023
    The rapid development of antimicrobial resistance due to broad antibiotic utilisation in the healthcare and food industries and the non-availability of novel antibiotics represents one of the most critical public health issues worldwide. Current advances in nanotechnology allow new materials to address drug-resistant bacterial infections in specific, focused, and biologically safe ways. The unique physicochemical properties, biocompatibility, and wide range of adaptability of nanomaterials that exhibit photothermal capability can be employed to develop the next generation of photothermally induced controllable hyperthermia as antibacterial nanoplatforms. Here, we review the current state of the art in different functional classes of photothermal antibacterial nanomaterials and strategies to optimise antimicrobial efficiency. The recent achievements and trends in developing photothermally active nanostructures, including plasmonic metals, semiconductors, and carbon-based and organic photothermal polymers, and antibacterial mechanisms of action, including anti-multidrug-resistant bacteria and biofilm removal, will be discussed. Insights into the mechanisms of the photothermal effect and various factors influencing photothermal antimicrobial performance, emphasising the structure–performance relationship, are discussed. We will examine the photothermal agents’ functionalisation for specific bacteria, the effects of the near-infrared light irradiation spectrum, and active photothermal materials for multimodal synergistic-based therapies to minimise side effects and maintain low costs. The most relevant applications are presented, such as antibiofilm formation, biofilm penetration or ablation, and nanomaterial-based infected wound therapy. Practical antibacterial applications employing photothermal antimicrobial agents, alone or in synergistic combination with other nanomaterials, are considered. Existing challenges and limitations in photothermal antimicrobial therapy and future perspectives are presented from the structural, functional, safety, and clinical potential points of view.
  • RAPID MANUFACTURING OF FLEXIBLE MICROSTRUCTURED PDMS SUBSTRATES, USING 3D DPL PRINTING TECHNIQUE, FOR FLEXIBLE PRESSURE SENSORS
    UPB Scientific Bulletin Series B Chemistry and Materials Science, 2023
  • Synthesis of ZnO/Au Nanocomposite for Antibacterial Applications
    Violeta Dediu, Mariana Busila, Vasilica Tucureanu, Florentina Ionela Bucur, Florina Silvia Iliescu, et al.
    Nanomaterials, 2022
    Annually, antimicrobial-resistant infections-related mortality worldwide accelerates due to the increased use of antibiotics during the coronavirus pandemic and the antimicrobial resistance, which grows exponentially, and disproportionately to the current rate of development of new antibiotics. Nanoparticles can be an alternative to the current therapeutic approach against multi-drug resistance microorganisms caused infections. The motivation behind this work was to find a superior antibacterial nanomaterial, which can be efficient, biocompatible, and stable in time. This study evaluated the antibacterial activity of ZnO-based nanomaterials with different morphologies, synthesized through the solvothermal method and further modified with Au nanoparticles through wet chemical reduction. The structure, crystallinity, and morphology of ZnO and ZnO/Au nanomaterials have been investigated with XRD, SEM, TEM, DLS, and FTIR spectroscopy. The antibacterial effect of unmodified ZnO and ZnO/Au nanomaterials against Escherichia coli and Staphylococcus aureus was investigated through disc diffusion and tetrazolium/formazan (TTC) assays. The results showed that the proposed nanomaterials exhibited significant antibacterial effects on the Gram-positive and Gram-negative bacteria. Furthermore, ZnO nanorods with diameters smaller than 50 nm showed better antibacterial activity than ZnO nanorods with larger dimensions. The antibacterial efficiency against Escherichia coli and Staphylococcus aureus improved considerably by adding 0.2% (w/w) Au to ZnO nanorods. The results indicated the new materials’ potential for antibacterial applications.
  • PDMS Based Microfluidics Fabrication Using 3D-Printed Molds
    Violeta Dediu, Mihaela Carp, Florina S. Iliescu, Edwin A. Laszlo, Cristina Pachiu, et al.
    Proceedings of the International Semiconductor Conference CAS, 2022
  • Point-of-care testing-the key in the battle against SARS-CoV-2 pandemic
    Florina Silvia Iliescu, Ana Maria Ionescu, Larisa Gogianu, Monica Simion, Violeta Dediu, et al.
    Micromachines, 2021
    The deleterious effects of the coronavirus disease 2019 (COVID-19) pandemic urged the development of diagnostic tools to manage the spread of disease. Currently, the “gold standard” involves the use of quantitative real-time polymerase chain reaction (qRT-PCR) for SARS-CoV-2 detection. Even though it is sensitive, specific and applicable for large batches of samples, qRT-PCR is labour-intensive, time-consuming, requires trained personnel and is not available in remote settings. This review summarizes and compares the available strategies for COVID-19: serological testing, Point-of-Care Testing, nanotechnology-based approaches and biosensors. Last but not least, we address the advantages and limitations of these methods as well as perspectives in COVID-19 diagnostics. The effort is constantly focused on understanding the quickly changing landscape of available diagnostic testing of COVID-19 at the clinical levels and introducing reliable and rapid screening point of care testing. The last approach is key to aid the clinical decision-making process for infection control, enhancing an appropriate treatment strategy and prompt isolation of asymptomatic/mild cases. As a viable alternative, Point-of-Care Testing (POCT) is typically low-cost and user-friendly, hence harbouring tremendous potential for rapid COVID-19 diagnosis.
  • E-skin: The dawn of a new era of on-body monitoring systems
    Alina-Cristina Bunea, Violeta Dediu, Edwin Alexandru Laszlo, Florian Pistriţu, Mihaela Carp, et al.
    Micromachines, 2021
  • Copper doping effect on the properties in ZnO films deposited by sol–gel
    Anca-Ionela Istrate, Iuliana Mihalache, Cosmin Romanitan, Oana Tutunaru, Raluca Gavrila, et al.
    Journal of Materials Science Materials in Electronics, 2021
  • Effective control of TEOS-PECVD thin film depositions
    Mihaela CARP, Violeta DEDIU, Florian PISTRITU, Edwin A. LASZLO, Ciprian ILIESCU
    Proceedings of the International Semiconductor Conference CAS, 2020
  • Structural and opto-electrical analysis of Cu doped ZnO thin films by sol-gel method
    Anca-Ionela Istrate, Violeta Dediu, Iuliana Mihalache, Cosmin Romanitan, Oana Tutunaru
    Proceedings of the International Semiconductor Conference CAS, 2019
  • Nb-TiO2/ZnO nanostructures for chemoresistive alcohol sensing
    Violeta Dediu, Viorica Musat, Ileana Cernica
    Applied Surface Science, 2019
  • Direct Writing Patterns for Gold Thin Film with DPN Technique
    Carp Mihaela, Pachiu Cristina, Dediu Violeta
    Proceedings of the International Semiconductor Conference CAS, 2018
  • Thermal decomposition of some sol-gel precursors for mesoporous TiO2-Based thin films for chemorezistive environmental sensors
    Violeta Dediu, Viorica Musat, Bogdan Jurca, Nicolae Ionut Cristea
    Revista De Chimie, 2017
  • Environmental impact assessment of odours from solid waste landfills located in highly urbanized areas
    Andrei Vasile, Valeriu Danciulescu, Tanase Gheorghita, Lidia Kim, Violeta Dediu
    Revista De Chimie, 2017
  • Ard treatment - batch vs. Continuous flow reaction systems for sulphate precipitation, a technical note
    Michal Molenda
    International Multidisciplinary Scientific Geoconference Surveying Geology and Mining Ecology Management Sgem, 2017
  • Single step metal and sulphate precipitation, a particular suitable mine water case
    Iraida Kirilchuk
    International Multidisciplinary Scientific Geoconference Surveying Geology and Mining Ecology Management Sgem, 2017
  • Ethanol and methanol sensing characteristics of Nb-doped TiO 2 porous thin films
    Violeta Nechita, Joop Schoonman, Viorica Musat
    Physica Status Solidi A Applications and Materials Science, 2012

RECENT SCHOLAR PUBLICATIONS

  • Cellulose–Silver and Cellulose–Gold Bioactive Nanocomposites Obtained Using SCOBY Purified Membranes
    V Dediu, M Buşilă, C Ungureanu, L Grigore-Gurgu, M Cotârleṭ, ...
    ACS Applied Bio Materials 8 (11), 9650-9663 , 2025
    2025
    Citations: 1
  • Thermally induced polymorphic changes in poly (vinylidene fluoride) thin layer investigated using micro-Raman spectroscopy
    M Purica, FC Comanescu, V Dediu
    Coatings 14 (12), 1520 , 2024
    2024
    Citations: 2
  • Pressure Mapping System at the Level of the Sole of the Foot
    F Pistritu, C Pârvulescu, M Gheorghe, V Dediu, ON Ionescu, P Schiopu, ...
    2024 International Semiconductor Conference (CAS), 313-316 , 2024
    2024
  • Antibacterial and photocatalytic activity of ZnO/Au and ZnO/Ag nanocomposites
    M Busila, V Musat, P Alexandru, C Romanitan, O Brincoveanu, ...
    International Journal of Molecular Sciences 24 (23), 16939 , 2023
    2023
    Citations: 54
  • Trends in photothermal nanostructures for antimicrobial applications
    V Dediu, J Ghitman, G Gradisteanu Pircalabioru, KH Chan, FS Iliescu, ...
    International Journal of Molecular Sciences 24 (11), 9375 , 2023
    2023
    Citations: 88
  • Rapid manufacturing of flexible microstructured PDMS substrates using 3D DPL printing technique for flexible pressure sensors
    F Pistritu, M Carp, V Dediu, C Parvulescu, M Vladescu, P Schiopu
    U.P.B. Sci. Bull., Series B 85 (4), 235-246 , 2023
    2023
    Citations: 2
  • Synthesis of ZnO/Au nanocomposite for antibacterial applications
    V Dediu, M Busila, V Tucureanu, FI Bucur, FS Iliescu, O Brincoveanu, ...
    Nanomaterials 12 (21), 3832 , 2022
    2022
    Citations: 37
  • PDMS Based Microfluidics Fabrication Using 3D-Printed Molds
    V Dediu, M Carp, FS Iliescu, EA Laszlo, C Pachiu, C Iliescu
    2022 International Semiconductor Conference (CAS), 243-246 , 2022
    2022
    Citations: 4
  • Point-of-care testing—the key in the battle against SARS-CoV-2 pandemic
    FS Iliescu, AM Ionescu, L Gogianu, M Simion, V Dediu, MC Chifiriuc, ...
    Micromachines 12 (12), 1464 , 2021
    2021
    Citations: 38
  • E-skin: The dawn of a new era of on-body monitoring systems
    AC Bunea, V Dediu, EA Laszlo, F Pistriţu, M Carp, FS Iliescu, ON Ionescu, ...
    Micromachines 12 (9), 1091 , 2021
    2021
    Citations: 72
  • Copper doping effect on the properties in ZnO films deposited by sol–gel
    AI Istrate, I Mihalache, C Romanitan, O Tutunaru, R Gavrila, V Dediu
    Journal of Materials Science: Materials in Electronics 32 (4), 4021-4033 , 2021
    2021
    Citations: 20
  • Effective control of TEOS–PECVD thin film depositions
    C Mihaela, V DEDIU, F PISTRIŢU, EA LASZLO, C ILIESCU
    2020 International Semiconductor Conference (CAS), 195-198 , 2020
    2020
    Citations: 3
  • Structural and opto-electrical analysis of Cu doped ZnO thin films by sol-gel method
    AI Istrate, V Dediu, I Mihalache, C Romanitan, O Tutunaru
    2019 International Semiconductor Conference (CAS), 233-236 , 2019
    2019
    Citations: 2
  • Nb-TiO2/ZnO nanostructures for chemoresistive alcohol sensing
    V Dediu, V Musat, I Cernica
    Applied Surface Science 488, 70-76 , 2019
    2019
    Citations: 21
  • Direct Writing Patterns for Gold Thin Film with DPN Technique
    C Mihaela, P Cristina, D Violeta
    2018 International Semiconductor Conference (CAS), 261-264 , 2018
    2018
  • Thermal Decomposition of Some Sol-Gel Precursors for Mesoporous TiO2-Based Thin Films for Chemorezistive Environmental Sensors
    V Dediu, V Musat, B Jurca, NI Cristea
    Revista de Chimie 68 (8), 1703-1707 , 2017
    2017
    Citations: 1
  • ARD TREATMENT-BATCH VS. CONTINUOUS FLOW REACTION SYSTEMS FOR SULPHATE PRECIPITATION, A TECHNICAL NOTE
    LR Dinu, I Balaiu, I Cristea, VR Badescu, V Dediu
    International Multidisciplinary Scientific GeoConference: SGEM 17, 101-107 , 2017
    2017
  • Environmental Impact Assessment of Odours from Solid Waste Landfills Located in Highly Urbanized Areas
    A Vasile, V Danciulescu, G Tanase, L Kim, V Dediu
    Revista De Chimie 68 (Issue 8), 1749-1751 , 2017
    2017
    Citations: 6
  • SINGLE STEP METAL AND SULPHATE PRECIPITATION, A PARTICULAR SUITABLE MINE WATER CASE
    LR Dinu, IN Cristea, V Dediu, M Stefanescu, MA Constantin
    International Multidisciplinary Scientific GeoConference: SGEM 17, 861-867 , 2017
    2017
  • Experimental models of characterization and analysis of industrial waste.
    L Kim, AM Muresan, A Cuciureanu, D Guta, M Arama, NI Cristea, V Dediu
    2017
    Citations: 14

MOST CITED SCHOLAR PUBLICATIONS

  • Trends in photothermal nanostructures for antimicrobial applications
    V Dediu, J Ghitman, G Gradisteanu Pircalabioru, KH Chan, FS Iliescu, ...
    International Journal of Molecular Sciences 24 (11), 9375 , 2023
    2023
    Citations: 88
  • E-skin: The dawn of a new era of on-body monitoring systems
    AC Bunea, V Dediu, EA Laszlo, F Pistriţu, M Carp, FS Iliescu, ON Ionescu, ...
    Micromachines 12 (9), 1091 , 2021
    2021
    Citations: 72
  • Antibacterial and photocatalytic activity of ZnO/Au and ZnO/Ag nanocomposites
    M Busila, V Musat, P Alexandru, C Romanitan, O Brincoveanu, ...
    International Journal of Molecular Sciences 24 (23), 16939 , 2023
    2023
    Citations: 54
  • Point-of-care testing—the key in the battle against SARS-CoV-2 pandemic
    FS Iliescu, AM Ionescu, L Gogianu, M Simion, V Dediu, MC Chifiriuc, ...
    Micromachines 12 (12), 1464 , 2021
    2021
    Citations: 38
  • Synthesis of ZnO/Au nanocomposite for antibacterial applications
    V Dediu, M Busila, V Tucureanu, FI Bucur, FS Iliescu, O Brincoveanu, ...
    Nanomaterials 12 (21), 3832 , 2022
    2022
    Citations: 37
  • Ethanol and methanol sensing characteristics of Nb‐doped TiO 2 porous thin films
    V Nechita, J Schoonman, V Musat
    physica status solidi (a) 209 (1), 153-159 , 2012
    2012
    Citations: 30
  • Nb-TiO2/ZnO nanostructures for chemoresistive alcohol sensing
    V Dediu, V Musat, I Cernica
    Applied Surface Science 488, 70-76 , 2019
    2019
    Citations: 21
  • Copper doping effect on the properties in ZnO films deposited by sol–gel
    AI Istrate, I Mihalache, C Romanitan, O Tutunaru, R Gavrila, V Dediu
    Journal of Materials Science: Materials in Electronics 32 (4), 4021-4033 , 2021
    2021
    Citations: 20
  • Experimental models of characterization and analysis of industrial waste.
    L Kim, AM Muresan, A Cuciureanu, D Guta, M Arama, NI Cristea, V Dediu
    2017
    Citations: 14
  • Environmental Impact Assessment of Odours from Solid Waste Landfills Located in Highly Urbanized Areas
    A Vasile, V Danciulescu, G Tanase, L Kim, V Dediu
    Revista De Chimie 68 (Issue 8), 1749-1751 , 2017
    2017
    Citations: 6
  • PDMS Based Microfluidics Fabrication Using 3D-Printed Molds
    V Dediu, M Carp, FS Iliescu, EA Laszlo, C Pachiu, C Iliescu
    2022 International Semiconductor Conference (CAS), 243-246 , 2022
    2022
    Citations: 4
  • Effective control of TEOS–PECVD thin film depositions
    C Mihaela, V DEDIU, F PISTRIŢU, EA LASZLO, C ILIESCU
    2020 International Semiconductor Conference (CAS), 195-198 , 2020
    2020
    Citations: 3
  • The determination of lead, chromium, arsenic and selenium in sediments and soil samples by electrothermal atomic absorption spectrometry using chemical modifiers.
    V Dediu, L Kim, C Cosma, D Guta
    2016
    Citations: 3
  • Thermally induced polymorphic changes in poly (vinylidene fluoride) thin layer investigated using micro-Raman spectroscopy
    M Purica, FC Comanescu, V Dediu
    Coatings 14 (12), 1520 , 2024
    2024
    Citations: 2
  • Rapid manufacturing of flexible microstructured PDMS substrates using 3D DPL printing technique for flexible pressure sensors
    F Pistritu, M Carp, V Dediu, C Parvulescu, M Vladescu, P Schiopu
    U.P.B. Sci. Bull., Series B 85 (4), 235-246 , 2023
    2023
    Citations: 2
  • Structural and opto-electrical analysis of Cu doped ZnO thin films by sol-gel method
    AI Istrate, V Dediu, I Mihalache, C Romanitan, O Tutunaru
    2019 International Semiconductor Conference (CAS), 233-236 , 2019
    2019
    Citations: 2
  • Cellulose–Silver and Cellulose–Gold Bioactive Nanocomposites Obtained Using SCOBY Purified Membranes
    V Dediu, M Buşilă, C Ungureanu, L Grigore-Gurgu, M Cotârleṭ, ...
    ACS Applied Bio Materials 8 (11), 9650-9663 , 2025
    2025
    Citations: 1
  • Thermal Decomposition of Some Sol-Gel Precursors for Mesoporous TiO2-Based Thin Films for Chemorezistive Environmental Sensors
    V Dediu, V Musat, B Jurca, NI Cristea
    Revista de Chimie 68 (8), 1703-1707 , 2017
    2017
    Citations: 1
  • Pressure Mapping System at the Level of the Sole of the Foot
    F Pistritu, C Pârvulescu, M Gheorghe, V Dediu, ON Ionescu, P Schiopu, ...
    2024 International Semiconductor Conference (CAS), 313-316 , 2024
    2024
  • Direct Writing Patterns for Gold Thin Film with DPN Technique
    C Mihaela, P Cristina, D Violeta
    2018 International Semiconductor Conference (CAS), 261-264 , 2018
    2018