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Nanoparticles as radiosensitizers in photon and hadron radiotherapy

Kubiak T.

Acta Bio-Optica et Informatica Medica. Inżynieria Biomedyczna

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2017

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Vol. 23, nr 1

29--36

EN

The article presents the possibility of utilizing nanoparticles as radiosensitizers both in X-ray and hadron therapy. Local reinforcement of the effect of the dose can be obtained by means of gadolinium, platinum, and gold nanoparticles, which are able to intensify the emission of photoelectrons and Auger electrons after the X-ray irradiation or increase the generation of low-energy electrons during hadron therapy. Such electrons induce water radiolysis in the vicinity of nanoparticles and create radicals that damage cancer cells. In addition to the presentation of the mechanisms responsible for radiosensitizing properties of nanoparticles, selected animal, cell culture and simulation experiments are mentioned. Attention is also drawn to the most important problems, which must be solved before clinical application of nanoparticles. The broadly defined biocompatibility is the basic feature required from radiosensitizing agents injected into the patient’s body. The effective delivery of nanoparticles to the target and obtaining the proper concentration and distribution within the tumor volume present a biggest challenge.

PL

Artykuł prezentuje możliwość wykorzystania nanocząstek jako radiouczulaczy zarówno w radioterapii fotonowej jak i terapii hadronowej. Lokalne wzmocnienie efektu dawki może być uzyskane dzięki nanocząstkom gadolinu, platyny i złota. Są one zdolne do zintensyfikowania emisji fotoelektronów i elektronów Augera przy napromienieniu fotonami X albo do zwiększenia emisji niskoenergetycznych elektronów podczas terapii hadronowej. Takie elektrony indukują radiolizę wody w sąsiedztwie nanocząstek, a generowane rodniki niszczą komórki nowotworu. Oprócz omówienia mechanizmów odpowiedzialnych za radiouczulające właściwości nanocząstek, przedstawiono wybrane eksperymenty symulacyjne oraz doświadczenia na hodowlach komórkowych i zwierzętach. Zwrócono również uwagę na najważniejsze problemy, które muszą zostać rozwiązane przed zastosowaniem nanocząstek w praktyce klinicznej. Szeroko zdefiniowana biokompatybilność jest podstawową własnością, jaką muszą posiadać środki radiouczulające, wstrzykiwane pacjentowi. Wciąż dużym wyzwaniem pozostaje efektywne dostarczanie nanocząstek tak, aby uzyskać ich wymagane stężenie i równomierny rozkład w objętości nowotworu.

2

Structure and surface studies on Ni-Mo alloys with polymers

Karolus M., Rówiński E., Łągiewka E.

Journal of Achievements in Materials and Manufacturing Engineering

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2006

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Vol. 18, nr 1-2

119--122

EN

Purpose: The aim of this paper is the presentation of the study results provided on structure and surface of the electrodeposited Ni-Mo alloys with different polymers. Design/methodology/approach: Composites based on Ni-Mo alloys with polytiophen, polypyrrole and polyethylene were obtained by electrochemical method. Depending on the potential and current density of electrodeposition and electropolymerization processes. Findings: The structural analysis made by X-ray diffraction shows that, in general, the solid solution of molybdenum in nickel is forming. The unit cell parameters of solid solution are slightly changing with the increasing of molybdenum contents in the alloy. The analysis of diffraction line broadening indicates presence of the Ni-Mo solution nanocrystallites in the deposited layers. Moreover, the Auger Electron spectroscopy (AES) verifies both the presence of the solid solution of molybdenum in nickel and presence of polymers in composites. The SEM images show the general microstructure typical for the grain structure. Research limitations/implications: Composites obtained by electrochemical method studied in this paper are unique in that the electrochemical methods can be used for processing ceramics, polymers, metals, composites and hybrid materials. Practical implications: The codeposition of alloys with polymers or polymerisation with alloy codeposition has created new opportunities in the preparation of novel composite materials. Conductive polymers have been investigated for use as the electrode materials for a number of applications including rechargeable batteries, electrochemical sensors etc. Originality/value: Using the electropolymerization and electrodeposition processes in preparation of the composites. The analysis of structure and surface of the electrodeposited Ni-Mo alloys with different polymers.

3

Preparation and structure of the electro-deposited Ni-Mo alloys with polymers

Karolus M., Niedbała J., Rówiński E., Łągiewka E., Budniok A.

Journal of Achievements in Materials and Manufacturing Engineering

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2006

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Vol. 16, nr 1-2

25--29

EN

Purpose: The aim of the paper is presentation the process of forming the Ni-Mo electrodeposited layers with polypyrrole, polytiophne and polyethylene. Design/methodology/approach: There are three ways of polymeriztion and layer depositon. Findings: In case of polytiophen + Ni-Mo – there is observed process of electropolymerization and Ni-Mo electrodeposition in the cathodic process. In case of polypyrrole + Ni-Mo – there is observed two-step process: electropolymerization in the anodic process and Ni-Mo electrodeposition in the cathodic process. So the composite is forming when the electrodes have worked alternately as the anode and as the cathode. In case of polyethylene + Ni-Mo – there is observed process of Ni-Mo electrodeposition with grains of polyethylene in the cathodic process. From structural analyses by X-ray diffraction it was noticed that the solid solution of Mo in Ni is forming. The unit cell parameters of solid solution are slightly changing with the incerasing of molybdenum contents in the alloy from the value 3.57 to 3.61 Å. In case of all polymers, the crystallite size calculated basing on the Williamson-Hall theory is about 5-6 nanometers. Practical implications: The codeposition of alloys with polymers or polymerisation with alloys codeposition has created new opportunities in the preparation of novel composite materials. Conductive polymers have been investigated for use as the electrode materials for a number of applications including rechargeable batteries, electrochemical sensors etc. Electrochemical method described in this paper is unique in that it can be used for processing ceramics, polymers, metals, composites and hybrid materials. Originality/value: Using the electopolymerization and electrodeposition processes in preparation of the composites.