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1
Content available Can titanium anodization lead to the formation of antimicrobial surfaces?
Jastrzębska A., Jastrzębski K., Jakubowski W.
Acta Innovations
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2018
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no. 26
21--27
EN
In recent years, there has been observed a growing need for novel, multifunctional materials that would not only replace, but also heal the damaged tissues. In this paper, the titanium dioxide films manufactured by anodic oxidation method are investigated. The study of their structurization and antimicrobial properties of the coatings is presented. Samples anodized in water solutions of ethylene glycol exhibited various character -from structurized to porous ones. As the study revealed, all samples acted anti-adhesive in terms of bacterial (Escherichia coli) and fungal (Candida albicans) surface colonisation.
2
Content available remote Evaluation of Candida albicans adhesion on AlSl-316L and Ti6Al4V in changing environmental conditions
Jastrzębska A., Jakubowski W., Jastrzębski K., Walkowiak B.
Engineering of Biomaterials
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2017
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Vol. 20, no. 141
2--7
EN
Currently, studies on the formation of microbiological biofilm on biomaterial surfaces and medical devices have become an important aspect in medicine. In vivo studies of the biofilm development show a high correlation between the environmental factors and attachment of microorganisms to artificial surfaces. This paper is devoted to determining the impact of specific environmental stimuli and parameters of cultivation of Candida albicans yeasts on their adhesion to AISI-316L and Ti6Al4V substrates. Environmental parameters include variable glucose concentrations in YPG growth medium (0, 2, 4 and 10% wt.). Development of yeasts was also analyzed in terms of variable nutrients level i.e. transferring samples from medium with low nutrients level to other with higher glucose content. Another studied parameter was incubation time and how much fungal colonization varies during 24 and 48 h of incubation. For all samples, the number of both live and dead cells was taken into account. The results showed that with the increase in sugar content in culture media, biofilm development was observed, especially on AISI 316L surface. Also, significant changes in the number of adhered cells were observed with higher glucose concentration in medium after 24 h of incubation. Almost similar number of attached cells was observed for low glucose concentrations on both studied materials.
3
Content available A review of mechanical properties of diamond-like carbon coatings with various dopants as candidates for biomedical applications
Jastrzębski K., Jastrzębska A., Bociąga A.
Acta Innovations
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2017
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no. 22
40--57
EN
In the modern world, there is an increasing demand for implants, and technologies connected with their manufacturing. One of the possible paths of their development relates to the use of diamond-like carbon coatings (DLC) for the improvement of surface properties of the biomaterials used for implants. Further improvement of the mentioned properties can be induced by means of doping of the coating. Among the elements which are under current investigation of researchers, the following can be placed: Ag, Si, F, Cu, Ti, Ca and P. This paper reviews previously published experimental data concerning mechanical and physicochemical properties of DLC coatings doped with Ag, Si, Cu, Ti, Ca, F and P as candidates for biomedical applications. Although plenty of articles are published in the mentioned field, the differences of coatings’ synthesis techniques, various sources of dopants and substrates, as well as conducted experiments make no consistent view about a possible solution for their future implementation in medicine. Some of the selected dopants (Cu, Ca, P), still require better characterisation of mechanical properties. There is a necessity to conduct studies of mechanical and physicochemical properties of DLC coatings doped with these elements. This will enable adjustment of the necessary technological parameters to biomedical requirements.
4
Content available Wpływ wielokrotnej sterylizacji na właściwości biomateriałów
Bociąga D., Jastrzębski K., Olejnik A., Świątek L., Marchwicka M.
Engineering of Biomaterials
|
2016
|
Vol. 19, no. 136
11--20
PL
Materiały metaliczne, między innymi stopy tytanu posiadają liczne właściwości, które pozwalają na ich częste stosowanie do produkcji wyrobów biomedycznych. Wszystkie urządzenia przeznaczone do celów medycznych przed użyciem muszą przejść proces sterylizacji. W praktyce niektóre z nich mogą być poddane więcej niż jednemu cyklowi sterylizacji przed umieszczeniem w ciele pacjenta. Pomimo tego, że sterylizacja jest jednym ze standardowych procesów, któremu podlegają wszystkie implanty, może być ona przyczyną zmian właściwości powierzchniowych materiału. Celem niniejszej pracy było sprawdzenie, jak proces wielokrotnej sterylizacji wpływa na właściwości powierzchniowe oraz odpowiedź komórkową dla grupy próbek wykonanych z dwóch stopów tytanu: Ti6Al4V i Ti6Al7Nb. Wypolerowane próbki obu stopów zostały poddane jednemu, pięciu oraz dziesięciu cyklom sterylizacji parowej. Próbki zostały przebadane pod kątem morfologii powierzchni (SEM) oraz składu chemicznego (EDS), a także topografii powierzchni (profilometr) oraz zwilżalności (pomiar kąta zwilżania metodą kropli). Badania cytotoksyczności i proliferacji komórek zostały przeprowadzone poprzez wykonanie testu live/dead z wykorzystaniem komórek kościotwórczych linii Saos-2. Przeprowadzone badania dowodzą, że wielokrotna sterylizacja powoduje pojawianie się zanieczyszczeń na powierzchni materiału oraz zwiększenie grubości warstwy tlenkowej. Wartości energii powierzchniowej oraz parametrów chropowatości wzrosły wraz ze wzrostem liczby cykli sterylizacji. Proliferacja komórek na wysterylizowanych próbkach ze stopów tytanu była mniejsza niż w przypadku stali nierdzewnej oraz próbki kontrolnej, chociaż żadna z próbek nie wykazała cytotoksyczności. Porównując dwa przebadane stopy tytanu, mniejsza proliferacja została odnotowana na próbkach Ti6Al7Nb.
EN
Due to their favorable properties, numerous metallic materials, including titanium alloys are chosen for biomedical applications. A final preparation step before the implantation of a metallic biomaterial is sterilization. In fact, some of the devices may undergo a multiple sterilization process before they are placed into the human body. Although sterilization is a part of a standard procedure, it might affect the surface properties of the material. The purpose of this study was to check the influence of multiple sterilization process on surface properties and biological response of two titanium alloys: Ti6Al4V and Ti6Al7Nb. Samples of both alloys were mechanically polished and subjected to 1, 5 or 10 stem sterilization cycles. Representative samples from each group were examined in term of surface morphology (SEM), chemical composition (EDS), topography (profilometer) and wettability (sessile drop technique). Cell proliferation and cytotoxicity assay were carried out with the use of live/dead test of Saos-2 osteoblast-like cells line. Examinations showed that the multiple sterilization process caused occasional appearance of contaminations on the surfaces, as well as increase in the oxide layer thickness. Values of surface energy and surface roughness parameters increased with the increasing number of sterilization cycles. Proliferation of cells on the surface of sterilized titanium alloys was lower than in the case of stainless steel and control sample. At the same time, none of the examined samples showed cytotoxicity. Comparing two titanium alloys, considerably lower number of cells was observed on Ti6Al7Nb surface.
5
Content available Ocena stopnia proliferacji komórek osteoblastopodobnych w kontakcie z powierzchniami stopu tytanu po piaskowaniu do różnego stopnia chropowatości
Bociąga D., Olejnik A., Jastrzębski K., Sobczyk-Guzenda A., Paradowska J.
Engineering of Biomaterials
|
2016
|
Vol. 19, no. 134
8--17
PL
Tytan i jego stopy są jednymi z najpopularniejszych biomateriałów metalicznych stosowanych w dzisiejszej implantologii. Mimo licznych zalet tych materiałów, wykonane z nich wszczepy często poddaje się dodatkowej obróbce powierzchni, której celem jest polepszenie integracji implantu z otaczającymi go tkankami. Spośród wielu dostępnych technik, jedną z najczęściej wykorzystywanych komercyjnie jest stosunkowo tania i szybka metoda piaskowania, polegająca na wystawianiu danego przedmiotu na kontakt ze strumieniem przyspieszonych cząstek materiału ściernego. Celem tej pracy była analiza wpływu piaskowania ścierniwem o różnej średnicy ziaren na właściwości obrabianej powierzchni elementów na bazie dwóch popularnych stopów tytanu: Ti-6Al-4V i Ti-6Al-7Nb. W celu scharakteryzowania uzyskanych powierzchni przeprowadzono badania ich topografii, składu chemicznego, chropowatości i zwilżalności. Ponadto, aby sprawdzić potencjalną reakcję organizmu na obecność obrobionych w ten sposób elementów dokonano oceny stopnia proliferacji ludzkich komórek kościotwórczych hodowanych w bezpośrednim kontakcie z przygotowanymi powierzchniami. Otrzymane wyniki wykazały wyraźną zależność pomiędzy stopniem chropowatości i składem chemicznym piaskowanych elementów, a zastosowanym do obróbki rodzajem medium ściernego. Badanie zachowania komórek będących w kontakcie z modyfikowanymi próbkami wykazało obniżoną skłonność osteoblastów do przylegania i namnażania na najbardziej chropowatych powierzchniach.
EN
Titanium and its alloys are very popular metallic biomaterials used for medical implants production. Despite numerous advantages of the bulk material, such implants are very often subjected to additional surface treatment in order to improve their integration within the body tissues. Besides many other available techniques, one of the most frequently used in the commercial sector is a fast and economically profitable process of abrasive blasting. It is a method in which a stream of accelerated particles collides with the implant surface what causes changes in the material properties. The following paper presents differences resulting from sandblasting of Ti-6Al-4V and Ti-6Al-7Nb specimens with blasting particles varying in size. In order to characterize the outcome of such the treatment, investigations of surface topography, chemical composition, roughness, and wettability were conducted. Finally, the behaviour of the osteoblast- -like cells adhered to the sandblasted Ti-6Al-4V and Ti-6Al-7Nb surfaces was assessed in order to evaluate potential body response towards the aforementioned materials. The results suggest a strong correlation between surface roughness, its chemistry and the type of blasting medium applied. Evaluation of the cell culture revealed a rapid decrease in cell proliferation rate onto the roughest surfaces.
6
Content available Evaluation of corrosion resistance of magnetron sputtered doped DLC coatings with use of salt spray technique
Jastrzębski K., Paradowska J., Jastrzębska A., Bociąga D.
Engineering of Biomaterials
|
2016
|
Vol. 19, no. 138 spec. iss.
104
7
Content available Control of the biological response to metallic biomaterials through application of the DLC coatings with dopants
Bociąga D., Olejnik A., Jastrzębski K., Jędrzejczak A., Świątek L., Grabarczyk J., Sobczyk-Guzenda A., Kamińska M., Jakubowski W., Komorowski P., Niedzielski P.
Engineering of Biomaterials
|
2016
|
Vol. 19, no. 138 spec. iss.
94
8
Content available Biological evaluation and surface properties of Ti-DLC coatings deposited by magnetron sputtering
Olejnik A, Sobczyk-Guzenda A., Świątek L., Jastrzębski K., Bociąga D.
Engineering of Biomaterials
|
2016
|
Vol. 19, no. 138 spec. iss.
105
EN
During the last few decades, a growing demand for medical implants may be observed on the market. This is a consequence of both the increasing number of people suffering from disabilities as well as technological development. As a result of growing number of trauma injuries, orthopaedic and bone implants are one of the branches of the medical device industry showing the fastest growth opportunities. However, the commonly applied metallic implants do not exhibit total chemical stability in human body environment and hence, possess relatively poor surface properties [1]. For that reason, even the corrosion resistant metals may release degradation products and cause adverse biological response1. Consequently, surface modifications of metallic implants which enhance the biological response of the human body towards the surface of the implant are recently gaining a lot of interest. One of the most extensively studied solutions include the application of diamond-like carbon (DLC) coatings which exhibit a combination of highly desirable properties in the context of biomedical applications [2]. Furthermore, the properties of DLC coatings, such as cell behaviour and body reaction towards its surface, may be further improved by doping with various elements [3]. Therefore, the modified DLC coatings are nowadays extensively researched in terms of their possible medical applications. In the case of orthopaedic implants the enhancement of the osseointegration process is highly desirable in order to assure the proper bone-healing, what according to the literature may be achieved by the addition of titanium (Ti). The incorporation of Ti into the DLC matrix does not only promote the bone marrow cells proliferation, but also simultaneously reduces the activity of the osteoclast-like cells as indicated by Shroeder et al. [4]. Similarly, also Thorwarth et al. demonstrated that carbon coatings containing TiO exhibit promising results concerning the proliferation and differentiation of human osteoblasts [5]. Nevertheless, in spite of the numerous studies considering the biological behaviour of Ti-incorporated DLC coatings, there is lack of conclusive reports considering the biological applications of coatings deposited by a magnetron sputtering technique. Taking this into consideration, a complex biological evaluation of Ti-DLC coatings followed by their surface characteristics was performed, since surface properties have a direct role in different post-implantation reactions including protein adsorption and cell proliferation [1]. The examined coatings were deposited on two commonly applied metallic biomaterials (AISI 316 LVM steel and Ti6Al7Nb alloy) using a magnetron sputtering technique. The surface characteristics of the deposited Ti-DLC coatings included the analysis of surface morphology (SEM), chemical composition and structure (XPS, FTIR) as well as surface wettability and surface free energy (sessile drop technique and Owens-Wendt’s model). The biological assessment of the deposited coatings was based on two complementary cell proliferation and viability assays (LIVE/DEAD and XTT test) performed with the use of two different cell lines, i.e. endothelial cells line EA.hy926 and osteoblast-like cells line Saos-2. The obtained results allowed to check the influence of titanium on the biological response of two different cell lines towards the Ti-DLC coatings deposited using magnetron sputtering method as well as to correlate the obtained results with the surface properties of the investigated coatings.
9
Content available remote On improved image encryption scheme based on chaotic map lattices
Jastrzębski K., Kotulski Z.
Engineering Transactions
|
2009
|
Vol. 57, iss. 2
89-104
EN
In this paper we examine one of the recently proposed chaotic image encryption algorithms, based on chaotic map lattices (CML). We show certain problems with the chaotic map, as well as errors in the designed algorithm. Then we propose a way to improve it and present a new version of algorithm and its implementation. At the end, we show the results of a security analysis and a comparison of both schemes. These results were obtained in the MSc Thesis.
10
Content available remote Zastosowanie metody szkolenia spawaczy TKS do precyzyjnego wykonania przetopu i lica elektrodą zasadową w pozycjach przymusowych.
Jastrzębski R., Cenin M., Jędrzejko J., Zieliński J., Jastrzębski K., Padula H.
Biuletyn Instytutu Spawalnictwa w Gliwicach
|
2005
|
R. 49, nr 3
61-64
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