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1

Ostatnie doniesienia na temat nanocząstek złota jako biomateriału w stomatologii i medycynie

Sadlik Julia, Szechyńska Joanna, Grzywacz Oliwia, Słota Dagmara, Piętak Karina, Florkiewicz Wioletta

Inżynieria Materiałowa

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2022

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Vol. 43, nr 3

14--19

PL

W ostatnich latach nanotechnologia znacząco rozwinęła się jako dziedzina nauki badająca obiekty o rozmiarach nanometrycznych. Każdego roku pojawia się coraz więcej doniesień i kolejnych koncepcji wykorzystujących różne rodzaje nanomateriałów, głównie w dziedzinie biomedycyny. W tym kontekście szczególnie interesujące są nanocząstki złota cieszące się rosnącym zainteresowaniem naukowców przede wszystkim ze względu na swoje unikalne właściwości optyczne i chemiczne. W przeglądzie skupiono się na ostatnich doniesieniach dotyczących wykorzystania nanocząstek złota, na omówieniu metod ich syntezy oraz właściwościach.

EN

In recent years, nanotechnology has significantly developed as a scientific field that studies nanometer-sized objects. Every year an increasing number of reports and new concepts using different types of nanomaterials appear, mainly in the biomedical field. In this context, gold nanoparticles are of particular interest; they are of growing interest to researchers mostly due to their unique optical as well as chemical properties. The following review focuses on recent reports on the use of gold nanoparticles, furthermore discussing the synthesis methods and their properties.

2

Laser generated gold nanoparticles for mass spectrometry of low molecular weight compounds

Płaza-Altamer Aneta, Kołodziej Artur, Nizioł Joanna, Ruman Tomasz

Chemical Technology & Biotechnology

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2022

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Vol. 3

61--69

PL

Preparation of gold nanoparticles (AuNPs) by pulsed fiber laser (PFL) laser generated nanomaterial (LGN) with the use of 2D galvo-scanner (2D GS) is described. The procedure of covering of custom-made stainless steel MALDI targets containing studied objects via nebulization is also presented. Examples of application of new method (PFL-2D GS LGN and nebulization) in laser desorption/ionization mass spectrometry (LDI MS) analyses are shown. These include tests with amino acids and also low molecular weight polymer.

3

Katalizatory złotowe osadzone na zeolitach

Walkowiak Adrian

Wiadomości Chemiczne

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2021

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[Z] 75, 11-12

1259--1293

EN

Heterogeneous gold catalysis is a relatively young but dynamically developing field of chemistry. At the end of the 1980s, Masatake Haruta and Graham Hutchings provided experimental evidence of high activity of supported gold catalysts in CO oxidation and acetylene hydrochlorination. Thus, these two researchers challenged the prevailing chemists’ belief that gold is almost completely chemically inert and catalytically inactive. Since then, gold catalysis has been constantly in the centre of attention of a wide array of scientists from around the world. However, there are still many questions about the nature of catalysts containing this noble metal, which inspires in-depth research in this field. From among various potential supports for gold heterogeneous catalysts, zeolites have drawn much attention thanks to several unique properties of this group of materials, among which the most important are high thermal stability and the presence of a system of pores of strictly defined sizes. Zeolites have extremely large surface area, which is desirable to obtain high dispersion of the active phase. The article provides a concise overview of the methods of gold nanoparticles deposition on zeolitic supports and catalytic applications of such materials. The first chapter sheds light on the properties of bulk and nano-sized Au and depicts the background of gold catalysis development. In the following part, a brief description of zeolites and their properties is delivered. The third chapter is devoted entirely to the description of several preparation methods of zeolite-supported gold catalysts and their applications in different catalytic processes. The following post-synthetic methods of zeolite modification with gold are described: impregnation, ion exchange, deposition-reduction, chemical vapour deposition, and grafting. The most important advantages and disadvantages of each method are summarized. The article concludes with a résumé of literature reports concerning the use of zeolitesupported gold catalysts in various processes. Special attention was paid to selective oxidation of alcohols and biomass-derived chemicals (e.g. glucose).

4

Synthesis of polymer-grafted gold nanoparticles via gamma radiation

Mokhtar Abdul Khaliq, Mohd Hidzir Norsyahidah, Rahman Irman Abdul, Mohamed Faizal, Radzal Nur Ain Mohd

Polimery

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2021

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T. 66, nr 11-12

584--588

EN

The research focused on the synthesis of polytetrafluoroethylene (PTFE) grafted with gold nanoparticles (AuNP). The Turkevich method, one of the common techniques of AuNP synthesis, was used to obtain an AuNP solution with a nanoparticle size of 20 nm. The PTFE-AuNP samples were subsequently irradiated and the absorbed doses were 0.5, 2, 5, 10 and 20 kGy. It was noticed that samples irradiated with 0.5 and 2 kGy were less stable and less concentrated than samples irradiated with higher doses due to aggregation and formation of precipitation after 30 days.

PL

W artykule omówiono technikę syntezy poli(tetrafluoroetylenu) (PTFE) szczepionego nanocząstkami złota (AuNP). Metodą Turkevicha, jedną z powszechnie stosowanych technik syntezy AuNP, uzyskano roztwór AuNP o wielkości cząstek 20 nm. Próbki roztworu PTFE-AuNP były następnie naświetlane promieniowaniem gamma; zaabsorbowane dawki promieniowania wyniosły 0,5, 2, 5, 10 oraz 20 kGy. Stwierdzono, że w przypadku dawek 0,5 i 2 kGy roztwór był mniej stabilny, a stężenie nanocząstek było niższe niż w przypadku wyższych dawek. Wiązało się to z agregacją i precypitacją nanocząstek po upływie 30 dni od naświetlania.

5

Radiolytic synthesis of gold nanoparticles in HEMA-based hydrogels : potentialities for imaging nanocomposites

Dziarabina Katsiaryna, Pinaeva Uliana, Kadłubowski Sławomir, Ulański Piotr, Coqueret Xavier

Nukleonika

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2021

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Vol. 66, No. 4

165--177

EN

This article reports on the radiolytic synthesis of nanocomposites containing gold nanoparticles (AuNPs) within two types of hydrogels based on 2-hydroxyethyl methacrylate (HEMA): (i) plain networks with various contents in ethylene glycol dimethacrylate (EGDMA), as a cross-linker and (ii) stimuli-responsive (SR) networks prepared from these monomers copolymerized with [2-(methacryloyloxy)ethyl]trimethylammonium chloride (MADQUAT) to confer pH-switchable swelling. Hydrogels were prepared by photopolymerization with well-defi ned composition and a high degree of monomer conversion using two experimental procedures, as xerogels or in aqueous solution. Besides MADQUAT, acrylic acid (AA) or N-isopropylacrylamide have been tested as copolymers, yielding pH- or temperature-sensitive hydrogels, respectively. Isothermal swelling in water was affected by monomer composition. Electron beam (EB) irradiation at doses up to 100 kGy of poly(HEMA) xerogels and water-swollen networks prepared with 0.5 wt% of EGDMA had a moderate impact on swelling characteristics and thermomechanical properties of the plain materials, whereas small amounts of extractables were formed. Poly(HEMA)-based nanocomposites containing AuNPs were successfully obtained by EB irradiation of samples swollen by aqueous solutions of Au(III). The effects of dose and cross-linking density on the formation of AuNPs were monitored by UV-visible spectroscopy. Irradiation at well-defined temperatures of the Au(III)-loaded SR hydrogels induced the formation of nanoparticles with size-dependent features, whereas the efficiency of Au(III) reduction at 10 kGy was not significantly affected by the network structure. EB-induced reduction of Au(III) in poly(HEMA) hydrogels using a lead mask to generate well-defined patterns yielded coloured and long-lasting images in the zones where the nanocomposite was formed.

6

Physicochemical Investigations of Hydrogels Containing Gold Nanoparticles Designed for Biomedical Use

Głąb Magdalena, Kudłacik-Kramarczyk Sonia, Drabczyk Anna, Grabowska Beata, Tyliszczak Bożena

Journal of Casting & Materials Engineering

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2021

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Vol. 5, no. 2

20--30

EN

Currently, many investigations are being performed to develop dressing materials with a positive effect on the wound healing process. In general, innovative dressings should ensure wound exudate absorption, constitute an external barrier limiting the possibility of wound contamination and, importantly, also provide therapeutic properties. This work is focused on obtaining materials with potential use as dressings for treatment of difficult-to-heal wounds. The synthesis methodology of acrylic hydrogels modified with selected modifiers, i.e. arabic gum, nanogold, bee pollen and chamomile extract, was developed. Next, the sorption properties of the materials were determined as well as their behavior during the incubation in fluids imitating the environment of the human body. Additionally, the impact of such an incubation on their structure was evaluated by FT-IR spectroscopy. It was proved that the modifiers affected the sorption properties of hydrogels, i.e. samples with additives showed even approx. 2.5-fold lower swelling ability. In turn, incubation of hydrogels in simulated body fluids did not cause any rapid changes in pH, which may indicate the biocompatibility of the tested materials with the tested fluids. Thus, it may be concluded that the developed materials show great application potential for biomedical purposes and may be subjected to more advanced studies such as cytotoxicity assessments towards selected cell lines.

7

Computational fluid dynamics simulation of heat transfer from densely packed gold nanoparticles to isotropic media

Radomski Piotr, Ziółkowski Paweł, de Sio Luciano, Mikielewicz Dariusz

Archives of Thermodynamics

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2021

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Vol. 42, no 3

87--113

EN

This work aims to determine and compare heat generation and propagation of densely packed gold nanoparticles (Au NPs) induced by a resonant laser beam (532 nm) according to the Mie theory. The heat flux propagation is transferred into the materials, which here are: silica glass; soda-lime-silica glass; borosilicate glass; polymethyl methacrylate (PMMA); polycarbonate (PC); and polydimetylosiloxane (PDMS). This analysis aims to select the optimum material serving as a base for using photo-thermoablation. On the other hand, research focused only on Newtonian heat transfer in gold, not on non-Fourier ones, like the Cattaneo approach. As a simulation tool, a computational fluid dynamics code with the second-order upwind algorithm is selected. Results reveal a near-Gaussian and Gaussian temperature distribution profile during the heating and cooling processes, respectively. Dependence between the maximum temperature after irradiation and the glass thermal conductivity is observed confirming the Fourier law. Due to the maximum heating area, the borosilicate or soda-lime glass, which serves as a base, shall represent an excellent candidate for future experiments.

8

Monte Carlo characterization of the gold nanoparticles dose enhancement and estimation of the physical interactions weight in dose enhancement mechanism

Mohammadzadeh Mohammad, Ghiasi Hosein

Polish Journal of Medical Physics and Engineering

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2020

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Vol. 26, Iss. 4

217--223

EN

Radiosensitization of the cancer cells by the heavy atoms of nanoparticles was the subject of some studies. But, the physical characterization to determine the weight of all interactions hasn’t been made numerically. The aim of this study was to calculate and compare the dose enhancement (DE) for different energies. The Monte Carlo simulation method was used in the current study. The influence of gold nanoparticles (GNP) size, beam quality, the GNP concentration, and dose inhomogeneity on the radiosensitization by DE was studied. A 35% increase in the photoelectric effect was observed while energy decreased from 18 MV to 300 kV. In the microscopic study which DE calculated in 30 μm from a single GNP, a 79% decreasing in DE within the first 1μm was seen and it declined to 2% in 30 μm from the GNP center. The effect was observed at small distances only. Our study revealed that the dose inhomogeneity around a nanoparticle is the main and very strong effect of DE on a macroscopic scale. In the location which 35% DE occurs most malignant cells survival will be effectively reduced. Our research indicates the need for further research.

9

Gold nanoparticles in an enhancement of antimicrobial activity

Wanarska Ewelina, Maliszewska Irena

Physicochemical Problems of Mineral Processing

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2020

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Vol. 56, iss. 6

269--279

EN

The effect of antimicrobial photodynamic therapy (aPDT) on Gram-positive bacterium Staphylocccus aureus was studied. Methylene blue (MB) at non-toxic concentration of 31.25µg/ml was used as a photosensitizer. LEDs diodes were used as a light source to study the effect of methylene blue alone and the MB-gold nanoparticle mixture on the viability of S. aureus cells. Biogenic gold nanoparticles (biolAuNPs, 10ppm) and chemically synthesized gold nanoparticles (chemAuNPs, 3ppm) were tested as enhancement agents. In the presence of MB alone as a photosensitizer, the killing effect was about 92% after 30min of irradiation. The aPDT therapy was enhanced by addition of biolAuNPs and chemAuNPs and killing rate of S. aureus was 95-96% after 30min of irradiation. The probable mechanism of enhancement of MB-mediated photodynamic bactericidal efficacy against S. aureus in the presence of gold nanoparticles is discussed leading to the conclusion that colloidal gold increases the accumulation of MB in bacterial cells.

10

Mixtures of selected n-alkanes and Au nanoparticels for optical fiber threshold temperature transducers

Przybysz N., Marć Paweł, Tomaszewska E., Grobelny Jarosław, Jaroszewicz Leszek R.

Opto-Electronics Review

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2020

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Vol. 28, No. 4

220--228

EN

Thermo-optic properties enhancement of the bi-stable temperature threshold sensors based on a partially filled photonic crystal fiber was reported. Previously tested transducers filled with a selected group of pure n-alkanes had in most cases differences between switching ON and OFF states. Therefore, the modification of filling material by using additional crystallization centers in the form of gold nanoparticles was applied to minimize this undesirable effect. The evaluation of the thermodynamic properties of pentadecane and its mixtures with 14 nm spherical Au nanoparticles based on the differential scanning calorimetry measurements was presented. Optical properties analysis of sensors prepared with these mixtures has shown that they are bounded with refractive index changes of the filling material. Particular sensor switches ON before melting process begins and switches OFF before crystallization starts. Admixing next group of n-alkanes with these nanoparticles allows to design six sensors transducers which change ON and OFF states at the same temperature. Thus, the transducers with a wider temperature range for fiber-optic multi-threshold temperature sensor tests will be used.

11

Bioactive Scaffolds for Skin Tissue Engineering Doped with Gold Nanoparticles Prepared from Waste Biomass

Radwan-Pragłowska Julia, Janus Łukasz, Piątkowski Marek, Sierakowska Aleksandra, Bogdał Dariusz

Inżynieria Mineralna

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2020

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no. 1, vol. 2

169--173

EN

Skin is the first barrier against pathogens and harmful external factors. Each damage of this tissue may cause microbial infection and danger to internal organs. Burns which may be a result of the exposure to radiation, chemicals or high temperature leads to the significant disruption of skin functions. The most promising method for this tissue recovery is regenerative medicine which requires application of three-dimensional biocompatible scaffolds. The biomaterials enable skin cells proliferation and new tissue formation under in vitro conditions. They can be prepared from synthetic and natural polymers and their combination. The application of additional components such as nanoparticles may enhance their mechanical properties and have a positive impact on fibroblasts divisions and extra cellular formation. One of the most promising raw materials for scaffolds is chitosan -a chitin derivative. It may be obtained from waste biomass such as crabs, shrimps and lobsters exoskeletons. Chitosan is non-toxic, biodegradable and have antibacterial properties. The aim of the following study was to obtain novel chitosan derivatives doped with the gold nanoparticles using only natural components such as orange peels and fatty acid derivative. Proposed modification strategy resulted in the preparation of the novel, biodegradable and biocompatible material with interesting properties. The products were analysed by UV-Vis and FT-IR methods. The scaffolds were investigated over their susceptibility to enzymatic degradation. Finally, the biomaterials were verified over their cyto-compability with human dermal fibroblasts. The results showed that the proposed synthesis pathway resulted in the obtained of the chitosan biomaterials with high potential in medicine.

PL

Skóra jest pierwszą barierą przed patogenami i szkodliwymi czynnikami zewnętrznymi. Każde uszkodzenie tej tkanki może powodować zakażenie drobnoustrojami i zagrożenie dla narządów wewnętrznych. Oparzenia, które mogą być wynikiem narażenia na promieniowanie, chemikalia lub wysoką temperaturę, prowadzą do znacznego zakłócenia funkcji skóry. Najbardziej obiecującą metodą tego odzyskiwania tkanki jest medycyna regeneracyjna, która wymaga zastosowania trójwymiarowych biokompatybilnych rusztowań. Biomateriały umożliwiają namnażanie komórek skóry i tworzenie nowych tkanek w warunkach in vitro. Można je wytwarzać z polimerów syntetycznych i naturalnych oraz ich kombinacji. Zastosowanie dodatkowych składników, takich jak nanocząstki, może poprawić ich właściwości mechaniczne i mieć pozytywny wpływ na podziały fibroblastów i tworzenie się komórek. Jednym z najbardziej obiecujących surowców na rusztowania jest chitozan - pochodna chityny.Można go uzyskać z biomasy odpadowej, takiej jak egzoszkielety krabów, krewetek i homarów. Chitozan jest nietoksyczny, biodegradowalny i ma właściwości antybakteryjne. Celem przedstawionych badań było uzyskanie nowych pochodnych chitozanu domieszkowanych nanocząstkami złota przy użyciu wyłącznie naturalnych składników, takich jak skórki pomarańczy i pochodna kwasu tłuszczowego. Proponowana strategia modyfikacji zaowocowała przygotowaniem nowego, biodegradowalnego i biokompatybilnego materiału o interesujących właściwościach. Produkty analizowano metodami UV-Vis i FT-IR. Rusztowania badano pod kątem ich podatności na degradację enzymatyczną. Na koniec biomateriały zweryfikowano pod kątem ich zgodności cytologicznej z ludzkimi fibroblastami skórnymi. Wyniki wykazały, że proponowany szlak syntezy zaowocował uzyskaniem biomateriałów chitozanu o wysokim potencjale w medycynie.

12

A Monte Carlo study on the radio-sensitization effect of gold nanoparticles in brachytherapy of prostate by 103Pd seeds

Jangjoo Amir Ghasemi, Ghiasi Hosein, Mesbahi Asghar

Polish Journal of Medical Physics and Engineering

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2019

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Vol. 25, Iss. 2

87--92

EN

103Pd seed is being used for prostate brachytherapy. Additionally, the dose enhancement effect of gold nanoparticles (GNP) has been reported in previous studies. The aim of this study was to characterize the dosimetric effect of gold nanoparticles in brachytherapy with a 103Pd source. Two brachytherapy seeds including 103Pd source was simulated using MCNPX Monte Carlo code. The seeds’ models were validated by comparing the MC with reported results. Then, GNPs (10 nm in diameter) with a concentration of 7mg Au/g were simulated uniformly inside the prostate of a humanoid computational phantom. Additionally, the dose enhancement factor (DEF) of nanoparticles was calculated for both modeled brachytherapy seeds. A good agreement was found between the MC calculated and the reported dosimetric parameters. For both seeds, an average DEF of 23% was obtained in tumor volume for prostate brachytherapy. The application of GNPs in conjunction with 103Pd seed in brachytherapy can enhance the delivered dose to the tumor and consequently leads to better treatment outcome.

13

Nanocząstki złota jako systemy celowanego dostarczania leku przeciwnowotworowego - cisplatyny

Wróblewska Anna, Matczuk Magdalena

Laboratorium - Przegląd Ogólnopolski

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2019

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nr 4

41--46

PL

Wykorzystanie nanotechnologii, dokładniej nanocząstek złota, stało się ostatnio obiektem wielu badań. Nanomateriały te oprócz szerokiego spektrum zastosowania charakteryzują się m.in.: biokompatybilnością, możliwościami akumulacji w komórkach nowotworowych, łatwą modyfikacją powierzchni. Cechy te powodują, że nanocząstki złota mogą zostać wykorzystane jako nośniki w systemach celowanego dostarczania leków. Stabilne związanie na powierzchni nanozłota, np. powszechnie stosowanej cisplatyny, może pozwolić na ograniczenie poważnych efektów ubocznych wywoływanych brakiem selektywności działania leku i skutkować zwiększeniem efektywności chemioterapii.

EN

The usage of nanotechnology, especially gold nanoparticles, has become the object of extensive research. Apart from a wide range of applications, these nanomaterials can be characterized by biocompatibility, a possibility to accumulate in cancer cells and a simplicity of their surface modification, among others. Due to the mentioned features gold nanoparticles can play the role of carriers in targeted drug delivery systems. The stable binding of the frequently used cisplatin, for example, on the nanogold surface may contribute to the reduction of the severe side effects of the therapy caused by the lack of selectivity of the drug’s action and may result in the increased effectiveness of chemotherapy.

14

The Design of RNA Biosensor Based on Nano-gold and Magnetic Nano-particle

Yang Jing, Yin Zhi-xiang, Cui Jian-zhong, Huang Kai-feng

Fundamenta Informaticae

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2019

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Vol. 164, nr 2-3

289--298

EN

Detecting the quality of drinking water is very important in researching the current status and predicting trends of variation, as well as fundamentally solving the water pollution problem. Recently, the application and development of biosensor provide a powerful analytical tool for detecting pollutants of drinking water, but high selectivity, specificity, short response time, and low cost are particularly desired in the detection process. In this paper, RNA molecules in combination with nano-gold and magnetic nano-particles were proposed as design strategies of the biosensor. The proposed designs have distinct advantages over conventional biosensor in the following aspects: the high affinity capacity, sensitivity, and practicability. Our work provided an alternative method to monitor the environment of drinking water, and may find applications in various monitoring fields.

15

Nanocząstki złota jako potencjalne metalo-nanomateriały teranostyczne - właściwości oraz analiza za pomocą ICP-MS

Matczuk M., Kur A., Legat J., Ruzik L.

Laboratorium - Przegląd Ogólnopolski

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2018

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nr 2

26--33

PL

Nanocząstki złota to jedne z najintensywniej testowanych metalonanomateriałów o potencjalnych właściwościach teranostycznych. Zarówno łatwość ich syntezy, unikalne właściwości fizyczne, jak i rozbudowana chemia powierzchni są powodami tak intensywnego nimi zainteresowania w materii wczesnego wykrywania i efektywnego leczenia nowotworu. Jednak by nanocząstki mogły być w przyszłości zakwalifikowane do badań klinicznych, niezbędny jest szereg testów in vitro i in vivo opisujących ich transport i metabolizm. Jedną z najczęściej stosowanych w tym celu technik jest ICP-MS.

EN

Gold nanoparticles are one of the most intensively tested metalo-nanomaterials in terms of their potential theranostic application. The reasons of such intensive attention paid to them, related to the early diagnosis and effective theraphy of cancer, are the simplicity of their synthesis, unique physical properties and the extensive surface chemistry. However, in order to qualify gold nanoparticles to clinical trials, it is necessary to carry out in vitro and in vivo tests describing their transportation and metabolic processes. One of the most frequently used technique adopted to fulfill this purpose is ICP-MS.

16

Otrzymywanie szkła czerwonego przy użyciu purpury Kasjusza

Woźniak M., Nocuń M., Pichniarczyk P.

Szkło i Ceramika

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2016

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R. 67, nr 6

11--14

PL

W pracy przedstawiono wyniki badań szkieł barwionych purpurą Kasjusza. Syntezę barwnika przeprowadzono w oparciu o informacje zawarte w literaturze z 1917 r. Do badań wybrano szkło ołowiowe ze względu na większą rozpuszczalność złota w tego typu szkłach. Wytopione szkła były bezbarwne, a w wyniku krystalizacji uzyskano barwę czerwoną. Intensywność i odcień barwy zależał od warunków krystalizacji. Rejestrowano fotograficznie barwę szkieł po krystalizacji, a w celu obiektywnego określenia zmian barwy wykonano analizy spektrofotometryczne.

EN

The paper presents the results of research conducted on glasses coloured with the Purple of Cassius. The synthesis of the dye was carried out based on information contained in the literature from 1917. The lead glass was selected for the survey due to the higher solubility of gold in these glasses. Molten glasses were colorless, and as a result of crystallization the red color was obtained. The intensity and hue depended on the crystallization conditions. The color of glass after crystallization was photographically registered, and spectrophotometric analysis was conducted in order to determine objectively the color changes.

17

Nanocząstki złota do aktywacji końskich płytek krwi

Mucha A., Nowak U.

Przemysł Chemiczny

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2016

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T. 95, nr 7

1337--1341

PL

Metodą redukcji kwasu chlorozłotowego, przy udziale polimeru stabilizującego polietylenoiminy, otrzymano nanocząstki złota. Pełną krew obwodową koni inkubowano wraz z uzyskanymi nanocząstkami, w celu sprawdzenia wpływu nanododatku na aktywację płytek krwi. Zastosowano trzy stężenia AuNPs w stosunku do pełnej krwi obwodowej: 1, 5 i 10%. Obecność nanocząstek złota w roztworze zbadano metodą spektrofotometryczną UV-Vis. Mikrostrukturę nanocząstek złota oraz morfologię płytek krwi zanalizowano za pomocą SEM. Testy ELISA pozwoliły na ocenę stężeń czynników wzrostu oraz cytokin w inkubowanych próbkach. Otrzymane wyniki wskazują, że nanocząstki złota mają wpływ na aktywację trombocytów.

EN

The Au nanoparticles were produced by chem. redn. of HAuCl4 in presence of polyethylenimine used as a stabilizer. Equine peripheral blood was incubated with the Au nanoparticles. The concn. of growth factors and cytokines in the incubated peripheral blood was detd. by ELISA. The Au nanoparticles activated the platelets.

18

Aktywność przeciwgrzybicza preparatu śliny zawierającego nanocząstki złota

Mystkowska J., Niemirowicz K., Tokajuk G., Łysik D., Lewkowicz E., Dąbrowski J. R., Bucki R.

Engineering of Biomaterials

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2016

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Vol. 19, no. 137

20--29

PL

Ślina naturalna jest jednym z najważniejszych płynów ustrojowych i pełni wiele istotnych funkcji w jamie ustnej. Jednakże, w pewnych sytuacjach, dochodzi do procesu zaburzenia jej wydzielania, co skutkuje pojawieniem się objawów hyposaliwacji (redukcji wydzielania śliny) lub kserostomii (suchość jamy ustnej). W takich przypadkach stosuje się substytuty śliny, których zadaniem jest pełnienie funkcji śliny naturalnej. W niniejszej pracy przygotowano i przetestowano preparaty śliny, których skład chemiczny oparty jest o mucynę pochodzenia zwierzęcego i gumę ksantanową, rozpuszczonych w buforowanym roztworze soli. Przygotowane preparaty śliny wzbogacono o nanocząstki złota, uzyskując roztwory o stężeniu 200 μg/ml. Następnie, przeprowadzono badania ich aktywności przeciwgrzybicznej (w stosunku do szczepu Candida albicans). Do badań biologicznych wykorzystano próbki materiału implantacyjnego powszechnie stosowanego w protetyce stomatologicznej (stop Co-Cr-Mo, Remanium 380+), który przetrzymywano w roztworze kontrolnym i preparatach śliny (z/bez dodatku nanocząstek złota) w czasie 72 h w temperaturze 37°C. Po inkubacji dokonano obserwacji mikroskopowych powierzchni próbek badanego stopu z wykorzystaniem konfokalnego laserowego mikroskopu skaningowego (CLSM). Uzyskane wyniki badań wykazują różnice pomiędzy testowanymi roztworami w zakresie obecności drobnoustrojów Candida albicans. Zaobserwowano, że obecność nanocząstek złota w preparacie śliny istotnie redukuje wzrost szczepu Candida na powierzchni testowanego stopu dentystycznego.

EN

Natural saliva is one of the most important biological fluids and it fulfils many important functions in oral cavity. However, in some cases, disorders of salivary gland functions may cause hyposalivation (reduction of saliva secretion) or xerostomia (dryness of the oral cavity). Thus, so-called saliva substitute preparations can be used to support the functions of saliva. In our work, saliva substitute was prepared on the basis of porcine gastric mucin and xanthan gum, both dissolved in saline buffer. Additionally, gold nanoparticles were added to tested solution with concentration of 200 μg/ml and biological characterisation was evaluated. Analysis of the candidacidal activity (against Candida albicans) of prepared saliva substitute with addition of gold nanoparticles was performed. Tests were carried out after keeping samples of dental material (Co-Cr-Mo alloy, Remanium 380) in control sample and saliva preparations (with and without gold nanoparticles) during 72 hours at 37°C. After incubation, tested surfaces were observed using confocal laser scanning microscopy (CLSM). The obtained results of microscopic observations showed differences between the tested preparations in the scope of presence of Candida albicans. It was observed that gold nanoparticles significantly reduced the growth of Candida albicans species at tested dental material.

19

Gold Nanoparticles Like A Matrix For Covalent Immobilization Of Cholesterol Oxidase – Application For Biosensing

Wojnarowska R., Polit J., Broda D., Gonchar M., Sheregii E. M.

Archives of Metallurgy and Materials

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2015

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Vol. 60, iss. 3

2289--2296

EN

Gold nanoparticles are emerging as promising agents for various areas of material science as well as nanotechnology, electronics and medicine. The interest in this material is provided due to its unique optical, electronic and molecular-recognition properties. This paper presents results of preparation, characterization and biofunctionalization of gold nanoparticles. Nanoparticles have been conjugated with the cholesterol oxidase enzyme in order to prepare the active element for biosensors. Cholesterol oxidase is one of the most important analytical enzyme, used for cholesterol assay in clinical diagnostics, and there is still a necessity in improvement of existing analytical techniques, including bio-nanotechnological approaches based on modern nanosystems. The prepared bio-nanosystem was characterized by the enzyme activity test. Obtained results showed a stable binding of the enzyme with nanoparticles and preserved the bioactivity approves which gives possibility to use the prepared bio-nanosystems for analytical purposes. The Surface Plazmon Resonance and the Surface Enhanced Raman Scattering as specific for nanocurriers effects were observed what enable us to research the oscillation spectra of enzyme. These spectra were compared with ones obtained by IR-spectroscopy. The vibrational lines are attributed to chemical functional groups existing in enzyme, for example, amino acids, amide groups as well as flavin – adenine dinucleotide cholesterol oxidase prosthetic group. By this way the identified spectral lines can be used as a distinguishing mark of enzyme.

PL

Nanocząstki złota zdają się być niezwykle obiecującym materiałem, który z powodzeniem może być wykorzystywany w różnych dziedzin inżynierii materiałowej, nanotechnologii, elektroniki czy medycyny. Zainteresowanie tym materiałem wynika z posiadanych przez niego unikatowych właściwości optycznych, elektronicznych i identyfikacji na poziomie molekularnym. W artykule przedstawiono wyniki prowadzonych badań dotyczących przygotowania, charakterystyki i biofunkcjonalizacji nanocząstek złota. Celem wytwarzania i łączenia nanocząstek złota z enzymem oksydazą cholesterolową było opracowanie aktywnego biologicznie elementu biosensora. Oksydaza cholesterolowa jest jednym z najważniejszych enzymów analitycznych, stosowanych w diagnostyce klinicznej do oznaczenia stężenia cholesterolu. Istnieje potrzeba doskonalenia istniejących metod analitycznych, między innymi poprzez wykorzystanie nowoczesnych nanomateriałów. Przeprowadzono badania aktywności enzymu immobilizowanego, jak również dokonano charakterystyki danego bionanosystemu za pomocą wybranych metod optycznych. Na podstawie uzyskanych wyników można stwierdzić, że wiązanie enzymu z nanocząstkami jest stabilne, a aktywność biologiczna została zachowana, co pozwala na przygotowanie bio-nanosystemu do celów analitycznych. Zaobserwowano również wystąpienie dwóch efektów optycznych charakterystycznych w przypadku zastosowania odpowiednich nanonośników: Powierzchniowego Rezonansu Plazmonów oraz Powierzchniowo Wzmocnionego Rozproszenia Ramanowskiego. Uzyskane widma były porównywane z widmami w podczerwieni. Zaobserwowane linie przypisano do charakterystycznych grup funkcyjnych, aminokwasów, wiązań peptydowych, jak również dinukleotydu flawinoadeninowego czyli grupy prostetycznej oksydazy cholesterolowej. Zidentyfikowane linie mogą być wykorzystywane jako marker analityczny dla danego enzymu.

20

Towards mechanisms of nanotoxicity - interaction of gold nanoparticles with proteins and DNA

Krupa P., Mozolewska M. A., Rasulev B., Czaplewski C., Leszczyński J.

TASK Quarterly : scientific bulletin of Academic Computer Centre in Gdansk

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2014

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Vol. 18, No 4

337--341

EN

Even though most of the existing studies of gold nanoparticles indicate that they are safe to use, some researchers show that specific forms of nanoparticles (e.g. nanorods) are able to destroy the cell membrane and very small nanoparticles (below 37nm in diameter) in high concentration have been deadly for mice. We used the Amber12 package to perform a series of molecular dynamics (MD) simulations of gold nanoparticles with various small proteins important for the human body and a DNA molecule to determine the interactions and consequently the possible toxicity of gold clusters. Lennard-Jones interactions were used to simulate the behavior of gold nanoparticles with biomacromolecules in water with an optimal set of parameters (selected based on a comparison of MD structures and structures computed by DFT). Gold nanoparticle structures were obtained as a result of MD simulations from an initial structure, where gold atoms were at a distance of 10 ̊ A from one another. A predicted BDNA structure of a palindromic sequence‘ CGCATGAGTACGC ’ and a 2 JYK molecule were used as representatives of the DNA molecule. The preliminary results show that, in particular small gold nanoparticle s, interact strongly with proteins and DNA by creating stable complexes, which can then cause harmful reactions to the human body when present in high concentration.