Abstract: The control of ferroelectric domain walls at the nanometric level leads to novel interfacial properties and functionalities. In particular, the comprehension of charged domain walls, CDWs, lies at the frontier of future nanoelectronic research. Whereas many of the effects have been demonstrated for ideal archetypes, such as single crystals, and/or thin films, a similar control of CDWs on polycrystalline ferroelectrics has not been achieved. Here, we unambiguously show the presence of charged domain walls on a leadfree (K,Na)NbO3 polycrystalline system. The appearance of CDWs is observed in situ by confocal Raman microscopy and second harmonic generation microscopy. CDWs produce an internal strain gradient within each domain. Specifically, the anisotropic strain develops a crucial piece in the ferroelectric domain switching due to the coupling between the polarization of light and the ferroelectric polarization of the nanodomain in the (K,Na)NbO3 ceramic. This effect leads to the tuning of the ferroelectric domain switching by means of the light polarization angle. Our results will help to understand the relevance of charged domain walls on the ferroelectric domain switching process and may facilitate the development of domain wall nanoelectronics by remote light control utilizing polycrystalline ferroelectrics.

Palavras-Chave: nanoelectronics; nanotechnology; ferroelectric materials; domain structure; raman spectroscopy; polycrystals

RUBIO-MARCOS, FERNANDO; DEL CAMPO, ADOLFO; ROJAS-HERNANDEZ, ROCIO E.; RAMIREZ, MARIOLA O.; PARRA, RODRIGO; ICHIKAWA, RODRIGO U.; RAMAJO, LEANDRO A.; BAUSA, LUISA E.; FERNANDEZ, JOSE F. Experimental evidence of charged domain walls in lead-free ferroelectric ceramics: light-driven nanodomain switching. Nanoscale, v. 10, n. 2, p. 705-715, 2018. DOI: 10.1039/c7nr04304j. Disponível em: http://repositorio.ipen.br/handle/123456789/29068. Acesso em: $DATA.

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Abstract: Interfacial or separate phase location of carbonaceous nanofillers (graphene and carbon nanotubes) in polymer blends with co-continuous phases can lead to double percolation behavior, significantly increasing rheological and electrical properties. The prediction of the morphology and the location of the nanofillers has been used as a tool to evaluate the proprieties of co-continuous polymer blends. This work aims to highlight the superior conductivity levels achieved using a low amount of carbon-based fillers, by the proper selection in a multiphase polymer matrix as a template for controlled dispersion and spatial distribution of the nanoparticles, offering a compromise between easy processability and enhanced performance. Here, two polymers (linear low-density polyethylene [LLDPE] and ethylene-co-methylacrylate [EMA]) and their cocontinuous blend (LLDPE/EMA) were loaded with nanofillers (few-layer graphene [FLG], few-walled carbon nanotube [FWCNT]) via continuous melt mixing in twin-screw extrusion, separate and simultaneously. It was observed that the addition of the nanofillers changed the co-continuity of the blend, with the probable migration of the nanofillers from the EMA (hydrophilic) phase to the LLDPE (hydrophobic) phase. Rheological percolation occurred preferentially in blends containing FWCNT and FLG/FWCNT. Electrical conductivity was observed in all compositions, with higher electrical conductivity being noticed in hybrids.

Palavras-Chave: nanocomposites; hybridization; nanotechnology; polyethylenes; polymers; electric conductivity; carbon nanotubes; graphene

NUNES, MARIO A.B.S.; MATOS, BRUNO R. de; SILVA, GLAURA G.; ITO, EDSON N.; MELO, TOMAS J.A. de; FECHINE, GUILHERMINO J.M. Hybrids nanocomposites based on a polymer blend (linear low-density polyethylene/poly(ethylene-co-methyl acrylate) and carbonaceous fillers (graphene and carbon nanotube). Polymer Composites, v. 42, n. 2, p. 661-677, 2021. DOI: 10.1002/pc.25856. Disponível em: http://repositorio.ipen.br/handle/123456789/31940. Acesso em: $DATA.

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Abstract: The main objective of this work was to present a general framework of the technology roadmap from a central competence of Nuclear and Energy Research Institute from Brazil. The approach provides a structured to strength the join to market mechanism design to survive in complex environment trends to shape the future. The technological innovation impact measures depend from (1) quality of diversified technology knowledge and (2) quality of diversified country industry knowledge. From this big view picture, the Technology Transfer Office took these two general dimensions of impact into account and divided them into four (4) sub-categories that explain potential benefits and performance results in areas such as: a) Current Projects and Programs, b) Patents, c) Education and Teaching and d) Scientific Publications. The sampling contemplated the big picture of performance related in National Management Information System and a repository proper in response to institutional performance growth and plans, programs and projects associated in Innovation key indicators and policy disclosure. The taxonomy to roadmapping innovation impact measure was centered in terms in two potential fields to shape the future: i) Nuclear Research Reactors and/or ii) Nanotechnology.

Palavras-Chave: nanotechnology; socio-economic factors; research reactors; appropriate technology

PERINI, ALINE A.; SHIRAISHI, GUILHERME F.; FREITAS, ANDERSON Z. Matching technological bid in smart cities initiatives: a case study of innovation fairs at research institute in Brazil. Journal of Business and Economics, v. 12, n. 6, p. 598-607, 2021. DOI: 10.15341/jbe(2155-7950)/06.12.2021/003. Disponível em: http://repositorio.ipen.br/handle/123456789/32881. Acesso em: $DATA.

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Abstract: The use of three-dimensional cell cultures has been widely used for efficacy and/or toxicity testing of compounds. One of the most promising systems, based on magnetic levitation, is dependent on proper cell magnetization, achieved through adsorption of iron-oxide nanoparticles on cell membranes. These particles must bare not only significant responses to magnetic fields, but also a stable mechanism to attachment to cells. This work proposes a simple, one-pot synthesis method to produce magnetite nanoparticles, using a Fe2+ precursor associated with amino acids under microwave heating, and successive steps to confer positive charges to particles. X-ray diffraction could confirm Fe3O4 composition, and TEM analysis showed cubic-like crystallites with less than 50 nm. Zeta-potential experiments showed that particles remained positively charged (20.98 ± 0.28 mV) in physiological pH, suggesting ability to attach to (negatively charged) cell membranes, observed through optical microscopy. Iron colloid was found to be non-cytotoxic in concentrations up to 8% in cell culture media. Finally, human prostate cancer cells were cultured in 96-well plates using magnetic levitation and could be kept 8 days in culture. The results showed a feasible way to produce spheroids relying on magnetic levitation, using a newly described method of magnetic and cell adherent nanoparticle production.

Palavras-Chave: nanotechnology; iron oxides; microwave equipment; synthesis; nanoparticles; iron oxides; paramagnetism; toxicity; x-ray diffraction

BONFIM, LETICIA; PASSOS, PRISCILA de Q.S.; GONÇALVES, KARINA de O.; COURROL, LILIA C.; SILVA, FLAVIA R. de O.; VIEIRA, DANIEL P. Microwave-mediated synthesis of iron-oxide nanoparticles for use in magnetic levitation cell cultures. Applied Nanoscience, v. 9, n. 8, p. 1707-1717, 2019. DOI: 10.1007/s13204-019-00962-1. Disponível em: http://repositorio.ipen.br/handle/123456789/30817. Acesso em: $DATA.

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Abstract: Monoclonal antibodies as polymeric nanoparticles are quite interesting and endow this new drug category with many advantages, especially by reducing the number of adverse reactions and, in the case of radiopharmaceuticals, also reducing the amount of radiation (dose) administered to the patient. In this study, a nanoradiopharmaceutical was developed using polylactic acid (PLA)/polyvinyl alcohol (PVA)/montmorillonite (MMT)/trastuzumab nanoparticles labeled with technetium-99m (99mTc) for breast cancer imaging. In order to confirm the nanoparticle formation, atomic force microscopy and dynamic light scattering were performed. Cytotoxicity of the nanoparticle and biodistribution with 99mTc in healthy and inducted animals were also measured. The results from atomic force microscopy showed that the nanoparticles were spherical, with a size range of ~200–500 nm. The dynamic light scattering analysis demonstrated that over 90% of the nanoparticles produced had a size of 287 nm with a zeta potential of -14,6 mV. The cytotoxicity results demonstrated that the nanoparticles were capable of reaching breast cancer cells. The biodistribution data demonstrated that the PLA/PVA/MMT/trastuzumab nanoparticles labeled with 99mTc have great renal clearance and also a high uptake by the lesion, as ~45% of the PLA/PVA/MMT/trastuzumab nanoparticles injected were taken up by the lesion. The data support PLA/PVA/MMT/trastuzumab labeled with 99mTc nanoparticles as nanoradiopharmaceuticals for breast cancer imaging.

Palavras-Chave: medicine; neoplasms; radiopharmaceuticals; nanotechnology; mammary glands; molecular structure; image processing; nanostructures; diagnosis; nuclear medicine

SARCINELLI, MICHELLE A.; ALBERNAZ, MARTA de S.; SZWED, MARZENA; ISCAIFE, ALEXANDRE; LEITE, KATIA R.M.; JUNQUEIRA, MARA de S.; BERNARDES, EMERSON S.; SILVA, EMERSON O. da; TAVARES, MARIA I.B.; SANTOS-OLIVEIRA, RALPH. Nanoradiopharmaceuticals for breast cancer imaging: development, characterization, and imaging in inducted animals. OncoTargets and Therapy, v. 9, p. 5847-5854, 2016. DOI: 10.2147/OTT.S110787. Disponível em: http://repositorio.ipen.br/handle/123456789/26786. Acesso em: $DATA.

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Abstract: Surface modification corresponds to a set of viable technological approaches to introduce antimicrobial properties in materials that do not have such characteristics. Antimicrobial materials are important to prevent the proliferation of microorganisms and minimize the transmission of diseases caused by pathogens. Herein, poly (lactic acid) (PLA) was decorated with nanocones through copper sputtering followed by a plasma etching. Antiviral assays by Quantitative Reverse Transcription-Polymerase Chain Reaction (RT-qPCR) show that nanostructured Cu-coated PLA has high antiviral activity against Omicron SARS-CoV-2, showing a relative reduction in the amplified RNA (78.8 ± 3.9 %). Atomic Force Microscopy (AFM), X-ray Photoelectron Spectroscopy (XPS), and wear-resistance tests show that 20 wear cycles disrupt the surface nanocone patterns and significantly reduce the Cu content at the surface of the nanostructured Cu-coated PLA, leading to total loss of the antiviral properties of nanostructured PLA against Omicron SARS-CoV-2.

Palavras-Chave: coronaviruses; polymers; lactic acid; copper; plasma; nanotechnology; wear

SILVA, DANIEL J. da; DURAN, ADRIANA; FONSECA, FERNANDO L.A.; PARRA, DUCLERC F.; BUENO, RODRIGO F.; ROSA, DERVAL S. Omicron SARS-CoV-2 antiviral on poly(lactic acid) with nanostructured copper coating: wear effects. Applied Surface Science, v. 623, p. 1-9, 2023. DOI: 10.1016/j.apsusc.2023.157015. Disponível em: http://repositorio.ipen.br/handle/123456789/34105. Acesso em: $DATA.

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Abstract: We report herein an innovative approach to prostate tumor therapy using tumor specific radioactive gold nanoparticles (198Au) functionalized with Mangiferin (MGF). Production and full characterization of MGF-198AuNPs are described. In vivo therapeutic efficacy of MGF-198AuNPs, through intratumoral delivery, in SCID mice bearing prostate tumor xenografts are described. Singular doses of the nano-radiopharmaceutical (MGF-198AuNPs) resulted in over 85% reduction of tumor volume as compared to untreated control groups. The excellent anti-tumor efficacy of MGF-198AuNPs are attributed to the retention of over 90% of the injected dose within tumors for long periods of time. The retention of MGF-198AuNPs is also rationalized in terms of the higher tumor metabolism of glucose which is present in the xanthanoid functionality of MGF. Limited/no lymphatic drainage of MGF-198AuNPs to various non-target organs is an attractive feature presenting realistic scope for the clinical translation of MGF-198AuNPs in for treating prostate cancers in human patients. The comparative analysis of MGF-198AuNPs with other radioactive gold nanoparticles, functionalized either with epigallocatechin gallate or the Gum Arabic, has revealed significantly superior tumoricidal characteristics of MGF-198AuNPs, thus corroborating the importance of the tumor-avid glucose motif of MGF. Oncological implications of MGF-198AuNPs as a new therapeutic agent for treating prostate and various solid tumors are presented.

Palavras-Chave: neoplasms; prostate; nuclear medicine; gold; nanoparticles; therapy; nanotechnology; radiation effects; brachytherapy

KATTI, K.V.; KHOOBCHANDANI, M.; THIPE, V.C.; AL-YASIRI, A.Y.; KATTI, K.K.; LOYALKA, S.K.; SAKR, T.M.; LUGAO, A.B. Prostate tumor therapy advances in nuclear medicine: green nanotechnology toward the design of tumor specific radioactive gold nanoparticles. Journal of Radioanalytical and Nuclear Chemistry, v. 318, n. 3, p. 1737-1747, 2018. DOI: 10.1007/s10967-018-6320-4. Disponível em: http://repositorio.ipen.br/handle/123456789/29425. Acesso em: $DATA.

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Abstract: Introduction: We report, herein, in vitro, and in vivo toxicity evaluation of silver nanoparticles stabilized with gum arabic protein (AgNP-GP) in Daphnia similis, Danio rerio embryos and in Sprague Dawley rats. Purpose: The objective of this investigation was to evaluate in vitro and in vivo toxicity of silver nanoparticles stabilized with gum arabic protein (AgNP-GP), in multispecies due to the recognition that toxicity evaluations beyond a single species reflect the environmental realism. In the present study, AgNP-GP was synthesized through the reduction of silver salt using the tri-alanine-phosphine peptide (commonly referred to as “Katti Peptide”) and stabilized using gum arabic protein. Methods: In vitro cytotoxicity tests were performed according to ISO 10993– 5 protocols to assess cytotoxicity index (IC50) values. Acute ecotoxicity (EC50) studies were performed using Daphnia similis, according to the ABNT NBR 15088 protocols. In vivo toxicity also included evaluation of acute embryotoxicity using Danio rerio (zebrafish) embryos following the OECD No. 236 guidelines. We also used Sprague Dawley rats to assess the toxicity of AgNP-GP in doses from 2.5 to 10.0 mg kg− 1 body weight. Results: AgNP-GP nanoparticles were characterized through UV (405 nm), core size (20± 5 nm through TEM), hydrodynamic size (70– 80 nm), Zeta (ζ) potential (- 26 mV) using DLS and Powder X ray diffraction (PXRD) and EDS. PXRD showed pattern consistent with the Ag (1 1 1) peak. EC50 in Daphnia similis was 4.40 (3.59– 5.40) μg L− 1. In the zebrafish species, LC50 was 177 μg L− 1. Oral administration of AgNP-GP in Sprague Dawley rats for a period of 28 days revealed no adverse effects in doses of up to 10.0 mg kg− 1 b.w. in both male and female animals. Conclusion: The non-toxicity of AgNP-GP in rats offers a myriad of applications of AgNP-GP in health and hygiene for use as antibiotics, antimicrobial and antifungal agents.

Palavras-Chave: nanoparticles; nanotechnology; fishes; antimitotic drugs; toxicity; aquatic organisms; daphnia; rats; gum acacia; in vitro; in vivo

MAZIERO, JOANA S.; THIPE, VELAPHI C.; ROGERO, SIZUE O.; CAVALCANTE, ADRIANA K.; DAMASCENO, KELME C.; ORMENIO, MATHEUS B.; MARTINI, GISELA A.; BATISTA, JORGE G.S.; VIVEIROS, WILLIAM; KATTI, KAVITA K.; KARIKACHERY, ALICE R.; MOHANDOSS, DARSHAKUMAR D.; DHURVAS, RASHMI D.; NAPPINNAI, MOHANAVELU; ROGERO, JOSE R.; LUGAO, ADEMAR B.; KATTI, KATTESH V. Species-specific in vitro and in vivo evaluation of toxicity of silver nanoparticles stabilized with gum arabic protein. International Journal of Nanomedicine, v. 15, p. 7359-7376, 2020. DOI: 10.2147/IJN.S250467. Disponível em: http://200.136.52.105/handle/123456789/31613. Acesso em: $DATA.

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