Andrada LAZEA-STOYANOVA

Dr. Andrada LAZEA-STOYANOVA

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Research Focus & Metrics

Academic Career Length

15Years (2012-Present)

(Calculated once Scilit publication data is synced: current year − year of first publication + 1)

Representative Publications

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7 April 2021 in Polymers
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Journal Article
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MMMonica MIRONESCU
Monica MIRONESCU
ALAndrada LAZEA-STOYANOVA
Andrada LAZEA-STOYANOVA
MBMarcela-Elisabeta Barbinta-Patrascu
Marcela-Elisabeta Barbinta-Patrascu
LVLidia-Ioana Virchea
Lidia-Ioana Virchea
DRDiana Rexhepi
Diana Rexhepi
CGCecilia Georgescu
Cecilia Georgescu
A critical overview of current approaches to the development of starch-containing packaging, integrating the principles of green chemistry (GC), green technology (GT) and green nanotechnology (GN) with those of green packaging (GP) to produce materials important for both us and the planet is given. First, as a relationship between GP and GC, the benefits of natural bioactive compounds are analyzed and the state-of-the-art is updated in terms of the starch packaging incorporating green chemicals that normally help us to maintain health, are environmentally friendly and are obtained via GC. Newer approaches are identified, such as the incorporation of vitamins or minerals into films and coatings. Second, the relationship between GP and GT is assessed by analyzing the influence on starch films of green physical treatments such as UV, electron beam or gamma irradiation, and plasma; emerging research areas are proposed, such as the use of cold atmospheric plasma for the production of films. Thirdly, the approaches on how GN can be used successfully to improve the mechanical properties and bioactivity of packaging are summarized; current trends are identified, such as a green synthesis of bionanocomposites containing phytosynthesized metal nanoparticles. Last but not least, bioinspiration ideas for the design of the future green packaging containing starch are presented.

1 April 2020 in Materials
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MBMariana Daniela Berechet
Mariana Daniela Berechet
Carmen GaidauCarmen Gaidau
Carmen Gaidau
Aleksandra NešićAleksandra Nešić
Aleksandra Nešić
Branka PilicBranka Pilic
Branka Pilic
Maria RâpăMaria Râpă
Maria Râpă
ALAndrada LAZEA-STOYANOVA
Andrada LAZEA-STOYANOVA
This research aimed to obtain biocompatible and antimicrobial nanofibres based on concentrated collagen hydrolysate loaded with thyme or oregano essential oils as a natural alternative to synthesis products. The essential oils were successfully incorporated using electrospinning process into collagen resulting nanofibres with diameter from 471 nm to 580 nm and porous structure. The presence of essential oils in collagen nanofibre mats was confirmed by Attenuated Total Reflectance -Fourier Transform Infrared Spectroscopy (ATR-FTIR), Ultraviolet–visible spectroscopy (UV–VIS) and antimicrobial activity. Scanning Electron Microscopy with Energy Dispersive Spectroscopy analyses allowed evaluating the morphology and constituent elements of the nanofibre networks. Microbiological tests performed against Staphylococcus aureus, Escherichia coli, Pseudomonas aeruginosa and Candida albicans showed that the presence of essential oils supplemented the new collagen nanofibres with antimicrobial properties. The biocompatibility of collagen and collagen with essential oils was assessed by in vitro cultivation with NCTC clone 929 of fibroblastic cells and cell viability measurement. The results showed that the collagen and thyme or oregano oil composites have no cytotoxicity up to concentrations of 1000 μg·mL−1 and 500 μg mL−1, respectively. Optimization of electrospinning parameters has led to the obtaining of new collagen electrospun nanofibre mats loaded with essential oils with potential use for wound dressings, tissue engineering or protective clothing.

21 August 2021 in Materials
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MBMarcela-Elisabeta Barbinta-Patrascu
Marcela-Elisabeta Barbinta-Patrascu
YGYulia Gorshkova
Yulia Gorshkova
Camelia UngureanuCamelia Ungureanu
Camelia Ungureanu
Nicoleta BadeaNicoleta Badea
Nicoleta Badea
GBGizo Bokuchava
Gizo Bokuchava
SPSanja Petrovic
Sanja Petrovic
The phyto-development of nanomaterials is one of the main challenges for scientists today, as it offers unusual properties and multifunctionality. The originality of our paper lies in the study of new materials based on biomimicking lipid bilayers loaded with chlorophyll, chitosan, and turmeric-generated nano-silver/silver chloride particles. These materials showed a good free radical scavenging capacity between 76.25 and 93.26% (in vitro tested through chemiluminescence method) and a good antimicrobial activity against Enterococcus faecalis bacterium (IZ > 10 mm). The anticancer activity of our developed bio-based materials was investigated against two cancer cell lines (human colorectal adenocarcinoma cells HT-29, and human liver carcinoma cells HepG2) and compared to one healthy cell line (human fibroblast BJ cell line). Cell viability was evaluated for all prepared materials after a 24 h treatment and was used to select the biohybrid with the highest therapeutic index (TI); additionally, the hemolytic activity of the samples was also evaluated. Finally, we investigated the morphological changes induced by the developed materials against the cell lines studied. Biophysical studies on these materials were done by correlating UV–Vis and FTIR absorption spectroscopy, with XRD, SANS, and SAXS methods, and with information provided by microscopic techniques (AFM, SEM/EDS). In conclusion, these “green” developed hybrid systems are an important alternative in cancer treatment, and against health problems associated with drug-resistant infections.

13 March 2020 in Materials
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IKIryna Kuchakova
Iryna Kuchakova
MIMaria-Daniela Ionita
Maria-Daniela Ionita
EIEusebiu Rosini Ionita
Eusebiu Rosini Ionita
ALAndrada LAZEA-STOYANOVA
Andrada LAZEA-STOYANOVA
SBSimona Brajnicov
Simona Brajnicov
ANAnton Nikiforov
Anton Nikiforov
Thin film deposition with atmospheric pressure plasmas is highly interesting for industrial demands and scientific interests in the field of biomaterials. However, the engineering of high-quality films by high-pressure plasmas with precise control over morphology and surface chemistry still poses a challenge. The two types of atmospheric-pressure plasma depositions of organosilicon films by the direct and indirect injection of hexamethyldisiloxane (HMDSO) precursor into a plasma region were chosen and compared in terms of the films chemical composition and morphology to address this. Although different methods of plasma excitation were used, the deposition of inorganic films with above 98% of SiO2 content was achieved for both cases. The chemical structure of the films was insignificantly dependent on the substrate type. The deposition in the afterglow of the DC discharge resulted in a soft film with high roughness, whereas RF plasma deposition led to a smoother film. In the case of the RF plasma deposition on polymeric materials resulted in films with delamination and cracks formation. Lastly, despite some material limitations, both deposition methods demonstrated significant potential for SiOx thin-films preparation for a variety of bio-related substrates, including glass, ceramics, metals, and polymers.

4 September 2017 in Plasma Processes and Polymers
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VMValentina Marascu
Valentina Marascu
ALAndrada LAZEA-STOYANOVA
Andrada LAZEA-STOYANOVA
CSCristian Stancu
Cristian Stancu
GDGheorghe Dinescu
Gheorghe Dinescu

31 October 2019 in Materials
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MCMadalina Elena Culica
Madalina Elena Culica
KKKornela Kasperczyk
Kornela Kasperczyk
RBRaluca Ioana Baron
Raluca Ioana Baron
GBGabriela Biliuta
Gabriela Biliuta
AMAna Maria Macsim
Ana Maria Macsim
Sergiu CoseriSergiu Coseri
Sergiu Coseri
This paper proposes a convenient route to oxidize the –CH2–OH groups in the water-soluble pullulan, using a new catalytic polymer-supported N-hydroxyphthalimide (NHPI) immobilized on polystyrene. The protocol involves the presence of sodium hypochlorite and sodium bromide. The conversion is possible at room temperature, atmospheric pressure, and pH = 10. The characterization of both the catalysts and oxidized pullulan was done using NMR and FTIR methods. Using polyelectrolyte titration with end-point indication by means of a particle-charge detector (PCD), we were able to assess the degree of electrokinetic charge in all oxidized samples as a consequence of the conversion of the –CH2–OH group into –COOH moieties. The possibility of recovery and recycling of the polymer-supported NHPI catalyst was tested for up to four cycles, since the morphological analyses performed on the catalysts using SEM revealed no significant changes.