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Silver nanoparticles deposited on calcium hydrogenphosphate – silver phosphate matrix; biological activity of the composite

Szmuc K., Kus-Liskiewicz M., Szyller Ł., Szmuc D., Stompor M., Zawlik I., Ruman T., Wołowiec S., Cebulski J.

Polish Journal of Chemical Technology

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2019

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Vol. 21, nr 2

6--13

EN

The composite containing nanosilver uniformly deposited on matrix composed of CaHPO4 x 2H2 O (brushite, ca 89 mass %), CaHPO4 (monteonite, ca 9.5 mass%), and Ag3 PO4 (0.5 mas%) was obtained by addition of calcium nitrate and silver nitrate aqueous solution at 30:1 Ca:Ag molar ratio into excess of (NH4 )2 PO4 solution at pH 5.0 – 5.5. The isolated solid was characterized by STEM, XRD, and LDI mass spectrometry. It has been found that nanosilver was uniformly distributed within composite as <10 nm diameter sized nanoparticles. Determination of silver by AAS showed that 60% of silver is present as Ag(0) nanoparticles, the present as matrix Ag3 PO4 as identified by XRD method. The composite showed strong growth inhibition in E. coli and P. aeruginosa strains, and moderate towards S. aureus. The C. albicans cells were the most resistant to the tested material, although still composite was moderately cytostatic for the yeast.

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Zastosowanie nanocząstek srebra w laserowej spektrometrii mas oraz w obrazowaniu MS : przegląd

Sekuła J., Nizioł J., Ruman T.

Wiadomości Chemiczne

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2016

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[Z] 70, 7-8

519--539

EN

Metallic nanoparticles, especially silver nanoparticles, have attracted much attention due to their unique physical, chemical and opto-electronic properties. Silver nanoparticles have been successfully applied as a matrix replacement for the laser desorption/ionization time-of-flight mass spectrometry (LDI-ToF-MS). Silver nanoparticles (AgNPs) can efficiently absorb ultraviolet laser radiation, transfer energy to the analyte and promote analyte desorption, but also constitute a source of silver ions suitable for analyte cationisation. Nanoparticles, producing spectra with highly reduced chemical background in the low m/z region, are perfectly suited for low-molecular weight compound analysis and imaging. AgNPs have been demonstrated to allow efficient capture of different chemical compounds (including amino acids, cholesterol, fatty acids) on their surface, thus efficiently promoting their desorption and gas phase cationisation. The minimum detectable amount for those organic and biological molecules is often in the fmol range [23]. Despite the fact that scientists have developed a variety of methods for the synthesis of silver nanoparticles, there are still problems with obtaining surfaces with nanoparticles of high durability and chemical purity. Recently, a successful application of cationic silver nanoparticles (AgNPs), which were placed on MALDI targets for highly sensitive detection of d-ribose at attomolar levels as well as analysis of biological samples such as urine and blood serum [51] was shown. The application of new 109AgNPET surface has been presented with examples of analysis of nucleosides and nucleic bases [60]. One of the main directions of development of LDI-MS is the imaging mass spectrometry (MSI), enabling the visualization of surface distribution of biological samples. The critical limitations of the spatial resolution of MALDI-MSI are the size of the organic matrix crystals and the analyte migration during the matrix application process. To overcome these problems, researchers tried to use nanoparticles as substitutes of organic matrices. In 2013 Ruman group presented that direct contact of the analysed object with Ag nanoparticle-covered target permits direct surface transfer of chemical compounds. The active surface becomes then a “chemical photograph” of an object and allows MS analysis and MS imaging [68].

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Medyczne zastosowania sit molekularnych

Długopolska K., Ruman T., Pogocki D., Danilczuk M.

Wiadomości Chemiczne

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2009

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[Z] 63, 11-12

1073-1088

EN

Molecular sieves are porous, crystalline materials usually synthetic or natural zeolites, that contain well-defined pores of precise and uniform size. The term zeolite originally described a group of natural crystalline aluminosilicates, however nowadays the term covers many different materials such as aluminophosphates or gallium-silicalites. During the last few decades microporous and mesoporous materials have been considered for medical use due to biological properties and stability in biological environment [1-4]. Zeolites have been investigated as drug carriers, dietetic supplements, antimicrobial agents or as adjuvants in anticancer therapy [3–9]. Unique "magnetic" zeolite was obtained by Shan et al. Zeolite nanocrystals were in situ combined with superparamagnetic magnetite (Fe3O4) nanoparticles in the hydrothermal synthesis procedure. An high amount of enzymes adsorption and a good biocatalytic performance is shown by those newly formed magnetite/zeolite composite nanoparticles [15]. Zeolite of the CuX type has been used as a support for a antitumoral drug-cyclophosphamide. The in vivo tests show that the intensity of the antitumoral effects of the CuX zeolitecyclophosphamide system is similar in comparison to the one achieved by cyclophosphamide alone [21]. Ion-exchanged zeolites have also been used as a novel approach to storage and delivery of nitric oxide (NO) [16]. Zeolite surface coatings offer antimicrobial protection through the controlled release of antimicrobial agent and can be applied to different types of surfaces or incorporated in many types of polymers [17, 18]. Rivera group prove that both zeolitic materials and drugs could be simultaneously administrated to a patient without any loss of an individual pharmaceutical effect of each product [22]. Zeolite matrix has been also used to stabilize erythromycin solutions. An existing commercial product based on diisopropylsebacate/ethanol solution of 4% erythromycin and zinc acetate (ZinerytŽ, Yamanouchi Pharma) has been compared to analogical system where active compounds are loaded into porous material [26]. Natural clinoptilolite is the main and active component of the antidiarrheal drug acting as adsorbent of bile acids, Aflatoxine B and Glucose [64]. Recent studies show that this material can also be utilized as an adjuvant in anticancer therapy [10–13, 46–47]. The new antacid drug NeutacidŽ is based on the neutralizing capacity of the purified natural zeolite – clinoptilolite from the Tasajera deposit (Cuba) for therapy of patients suffering from hyperacidity produced by gastric dyspepsia and gastric-duodenal ulcer [50]. Mesoporous material MCM-41, due to the pore size tunability and functionalization possibilities, can especially encapsulate a variety of different drug molecules and release them in controlled ways [27, 28, 30–36]. Zeolites containing silver ions are used as antimicrobial agents [53–57]. Zeolites are the main ingredient of commercially available anti-bleed agents [67].

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Zastosowanie derywatyzacji w metodach chromatograficznych w analizie śladowej

Kalembkiewicz J., Ruman T.

Wiadomości Chemiczne

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2004

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[Z] 58, 3-4

263--276

EN

Derivatization is a modern method used in both organic and inorganic analytical chemistry. Application of derivatization to determine trace quantity of compounds requires very sensitive detection techniques. That combined with separation of analyzed compounds, makes the chromatographic systems like GC (gas chromatography) and HPLC (high performance liquid chromatography) especially useful in the analysis. There are mainly three routes in trace analysis of derivatized compounds. One can obtain derivative before performing a column separation (pre-column technique), which can be done both inside or outside chromatographic apparatus, or after column separation (post-column technique). The third method is based on dcrivatization reaction taking place simultaneously with column separation and requires special column filling which is resistant to derivatization reagents. There are several methods used to obtain derivatized compounds suitable for chromatographic methods. Acylation adapted to determine traces of amphetamine, methamphetamine and their metabolites allows lowering the detection level to 1 ppb. Very important part of derivatization methods in trace analysis is a determination of heavy metals via sodium tetraalkylborate alkylation with AED detection (atomic emission detection). Organometallic traces can be derivatized with tetraborate salts with AAD detection (atomic absorption detection). Less known methods like condensation and esterification are also very useful with suitable detector. For example, determination of ketones and aldehydes via derivatization with pentafluorophenylhydrazine allows to lower detection level down to 10^(-14) mol. Esterification of fatty acids with 9-(2-hydroxyethyl)carbazole performed on HPLC column gives full separation of esters with detection limit being around 45 fmol.