Cristian Nicolae Mihailescu

Dr. Cristian Nicolae Mihailescu


Research Focus & Metrics

Academic Career Length

7Years (2020-Present)

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

Representative Publications

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7 January 2022 in Coatings
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MBMaria Badiceanu
Maria Badiceanu
SASinziana Andreea Anghel
Sinziana Andreea Anghel
NMNatalia Mihailescu
Natalia Mihailescu
Anita Ioana VisanAnita Ioana Visan
Anita Ioana Visan
CMCristian Nicolae Mihailescu
Cristian Nicolae Mihailescu
Ion MihailescuIon Mihailescu
Ion Mihailescu
The development of new biological devices in response to market demands requires continuous efforts for the improvement of products’ functionalization based upon expansion of the materials used and their fabrication techniques. One viable solution consists of a functionalization substrate covered by layers via an appropriate deposition technique. Laser techniques ensure an enhanced coating’s adherence to the substrate and improved biological characteristics, not compromising the mechanical properties of the functionalized medical device. This is a review of the main laser techniques involved. We mainly refer to pulse laser deposition, matrix-assisted, and laser simple and double writing versus some other well-known deposition methods as magnetron sputtering, 3D bioprinting, inkjet printing, extrusion, solenoid, fuse-deposition modeling, plasma spray (PS), and dip coating. All these techniques can be extended to functionalize surface fabrication to change local morphology, chemistry, and crystal structure, which affect the biomaterial behavior following the chosen application. Surface functionalization laser techniques are strictly controlled within a confined area to deliver a large amount of energy concisely. The laser deposit performances are presented compared to reported data obtained by other techniques.

4 February 2023 in Nanomaterials
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Luiza-Izabela JingaLuiza-Izabela Jinga
Luiza-Izabela Jinga
LSLivia Elena Sima
Livia Elena Sima
CICristina Stefana Iosub
Cristina Stefana Iosub
PFPaula Ecaterina Florian
Paula Ecaterina Florian
MIMadalina Icriverzi
Madalina Icriverzi
Gabriel SocolGabriel Socol
Gabriel Socol
In this study, we report on the synthesis of L-Cysteine (L-Cys)-coated magnetic iron oxide nanoparticles (NPs) loaded with doxorubicin (Dox). The Fe3O4-L-Cys-Dox NPs were extensively characterized for their compositional and morpho-structural features using EDS, SAED, XRD, FTIR and TEM. XPS, Mӧssbauer spectroscopy and SQUID measurements were also performed to determine the electronic and magnetic properties of the Fe3O4-L-Cys-Dox nanoparticles. Moreover, by means of a FO-SPR sensor, we evidenced and confirmed the binding of Dox to L-Cys. Biological tests on mouse (B16F10) and human (A375) metastatic melanoma cells evidenced the internalization of magnetic nanoparticles delivering Dox. Half maximum inhibitory concentration IC50 values of Fe3O4-L-Cys-Dox were determined for both cell lines: 4.26 µg/mL for A375 and 2.74 µg/mL for B16F10, as compared to 60.74 and 98.75 µg/mL, respectively, for unloaded controls. Incubation of cells with Fe3O4-L-Cys-Dox modulated MAPK signaling pathway activity 3 h post-treatment and produced cell cycle arrest and increased apoptosis by 48 h. We show that within the first 2 h of incubation in physiological (pH = 7.4) media, ~10–15 µM Dox/h was released from a 200 µg/mL Fe3O4-L-Cys-Dox solution, as compared to double upon incubation in citrate solution (pH = 3), which resembles acidic environment conditions. Our results highlight the potential of Fe3O4-L-Cys-Dox NPs as efficient drug delivery vehicles in melanoma therapy.

22 February 2020 in Nanomaterials
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INIrina Negut
Irina Negut
LFLaura Floroian
Laura Floroian
CRCarmen Ristoscu
Carmen Ristoscu
CMCristian Nicolae Mihailescu
Cristian Nicolae Mihailescu
Julia C. Mirza-RoscaJulia C. Mirza-Rosca
Julia C. Mirza-Rosca
Ion MihailescuIon Mihailescu
Ion Mihailescu
Aseptic loosening and periprosthetic infections are the main causes of implant failure. Strategies to mitigate this drawback are therefore mandatory to avoid primary and revision replacement surgeries. A functional bioapatite–biopolymer double nanostructure fabricated by matrix-assisted pulsed laser evaporation to prevent infection of orthopedic and dental implants could promote osseointegration and ensure controlled delivery of natural antimicrobial drugs. The synthesized nanostructure consists of two overlapping layers, the lower from a biocompatible polymer for anticorrosive protection, and the upper of bioactive glass incorporating antimicrobial plant extract, acting as a potential drug delivery system. Morphology, composition, adherence, ability for drug delivery and biological properties (cytotoxicity and antimicrobial effect) were studied. Structures proved compact and stable, conserving a remarkable drug delivery ability for more than 21 days, i.e., enough to ensure long-term microbes’ eradication.

27 March 2020 in Coatings
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VAVictor Aurel Andrei
Victor Aurel Andrei
Cristiana RadulescuCristiana Radulescu
Cristiana Radulescu
VMViorel Malinovschi
Viorel Malinovschi
AMAlexandru Horia Marin
Alexandru Horia Marin
ECElisabeta Coaca
Elisabeta Coaca
Ioan Alin BucuricaIoan Alin Bucurica
Ioan Alin Bucurica
AISI 316 steel has good corrosion behavior and high-temperature stability, but often prolonged exposure to temperatures close to 700 °C in aggressive environments (e.g., in boilers and furnaces, in nuclear installations) can cause problems that lead to accelerated corrosion degradation of steel components. A known solution is to prepare alumina ceramic coatings on the surface of stainless steel. The aim of this study is to obtain aluminum oxide ceramic coatings on 316L austenitic steel, by Plasma Electrolysis Oxidation (PEO), using a pulsed unipolar power supply. The structures obtained by PEO under various experimental conditions were characterized by XPS, SEM, XRD, and EDS analyses. The feasibility was proved of employing PEO in NaAlO2 aqueous solution using a pulsed unipolar power supply for ceramic–like aluminum oxide films preparation, with thicknesses in the range of 20–50 μm, and a high content of Al2O3 on the surface of austenitic stainless steels.

22 February 2022 in Coatings
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Dorel Florin AlbuDorel Florin Albu
Dorel Florin Albu
Jeanina LunguJeanina Lungu
Jeanina Lungu
Gianina Popescu-PelinGianina Popescu-Pelin
Gianina Popescu-Pelin
CMCristian Nicolae Mihailescu
Cristian Nicolae Mihailescu
Gabriel SocolGabriel Socol
Gabriel Socol
Ion MihailescuIon Mihailescu
Ion Mihailescu
Active semiconductor layers of TiO2 were synthesized via pulsed laser deposition in He, N2, O2, or Ar to manufacture DSSC structures. As-prepared nanostructured TiO2 coatings grown on FTO were photosensitized by the natural absorption of the N719 (Ruthenium 535-bis TBA) dye to fabricate photovoltaic structures. TiO2 photoanode nanostructures with increased adsorption areas of the photosensitizer (a combination with voluminous media) were grown under different deposition conditions. Systematic SEM, AFM, and XRD investigations were carried out to study the morphological and structural characteristics of the TiO2 nanostructures. It was shown that the gas nature acts as a key parameter of the architecture and the overall performance of the deposited films. The best electro-optical performance was reached for photovoltaic structures based on TiO2 coatings grown in He, as was demonstrated by the short-circuit current (Isc) of 5.40 mA, which corresponds to the higher recorded roughness (of 44 ± 2.9 nm RMS). The higher roughness is thus reflected in a more efficient and deeper penetration of the dye inside the nanostructured TiO2 coatings. The photovoltaic conversion efficiency (η) was 1.18 and 2.32% for the DSSCs when the TiO2 coatings were deposited in O2 and He, respectively. The results point to a direct correlation between the electro-optical performance of the prepared PV cells, the morphology of the TiO2 deposited layers, and the crystallinity features, respectively.

10 April 2021 in Catalysts
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Elena-Alexandra Ilie (Săndulescu)Elena-Alexandra Ilie (Săndulescu)
Elena-Alexandra Ilie (Săndulescu)
CACrina Anastasescu
Crina Anastasescu
Florica PapaFlorica Papa
Florica Papa
Monica PavelMonica Pavel
Monica Pavel
Anca VasileAnca Vasile
Anca Vasile
Ioan BalintIoan Balint
Ioan Balint
The specific roles played by both support and noble metals in light absorption, charge separation, and the formation of ·OH and O2− (ROS) are analyzed for light-triggered oxidation of phenol (Ph) over pristine and over noble metal (Ag, Au, Pt) -loaded TiO2. Experiments show that the supported noble metals act as a light visible absorber, assist the separation of photo-charges and reduction of O2 to O2−. The O2− oxidizes mildly Ph to oxygenated products (hydroquinone, benzoquinone, and 1,2-dihydroxibenzene). In a parallel process, ·OH radicals, yielded by TiO2, mineralize Ph to CO2 by fast reaction sequences. Radical quenching and photo electrochemical measurements (surface photovoltage) confirm independently that the production of ·OH and O2− scale with oxidative conversion of Ph. The selectivity to CO2 and mild oxidation products is the result of the interplay between catalyst activity for ·OH and for O2− production.