Drug-Eluting Stents and Balloons—Materials, Structure Designs, and Coating Techniques: A Review

Controlled drug delivery is a matter of interest to numerous scientists from various domains, as well as an essential issue for society as a whole. In the treatment of many diseases, it is crucial to control the dosing of a drug for a long time and thus maintain its optimal concentration in the tissue. Heart diseases are particularly important in this aspect. One such disease is an obstructive arterial disease affecting millions of people around the world. In recent years, stents and balloon catheters have reached a significant position in the treatment of this condition. Balloon catheters are also successfully used to manage tear ducts, paranasal sinuses, or salivary glands disorders. Modern technology is continually striving to improve the results of previous generations of stents and balloon catheters by refining their design, structure, and constituent materials. These advances result in the development of both successive models of drug-eluting stents (DES) and drug-eluting balloons (DEB). This paper presents milestones in the development of DES and DEB, which are a significant option in the treatment of coronary artery diseases. This report reviews the works related to achievements in construction designs and materials, as well as preparation technologies, of DES and DEB. Special attention was paid to the polymeric biodegradable materials used in the production of the above-mentioned devices. Information was also collected on the various methods of producing drug release coatings and their effectiveness in releasing the active substance

Biokoncentracja rtęci i metali ciężkich przez korę platana klonolistnego

Continuous civilization progress, urbanization, and growing level of industrialization cause the fact that the contents of mercury and heavy metals in the natural environment is increasing, posing a threat to proper ontogenesis of all living organisms. Thus it is justified to monitor and control the accumulation of the above-mentioned elements in the environment. The main goal of our research was to determine whether maple-leaf plane tree (Platanus x acerifolia) may be used as a bioindicator of the air pollutants. This tree may be found all across Central Europe, it is quite resistant to different environment pollutions, and, what is very important, it sheds the bark every autumn. The research covered a determination of the analytical procedure capable of quantitive analysis of the contents of some given heavy metals: copper, zinc, iron, mercury and sulfur. The results and correctness of the procedure of the preparation of the bark samples for the analysis were confirmed by the research of a certified material (BCR-062 Olive leaves). Particular attention was put to the influence of the separated stages of the sample preparation (washing, drying, grinding down), especially for the mercury analysis due to the fact that this element is characterized by high volatility. To broaden the analysis, the samples were taken from different parts of the trees: limbs, trunks, and roots, as well as from different places, such as high-traffic streets, parks, and from different cities of Poland and Europe. Total mercury contents were measured by means of automatic Mercury Analyzer MA-2. The quantification determination of the transient-metal ions was performed on a emission spectrometer with inductively coupled plasma VARIAN VISTA-MPX.Ciągły rozwój cywilizacyjny, urbanizacja, postępujące uprzemysłowienie sprawiają, iż zawartość rtęci i metali ciężkich w środowisku naturalnym wzrasta i stwarza zagrożenie dla prawidłowego rozwoju wszystkich organizmów. Wydaje się więc celowe, aby monitorować i kontrolować akumulowanie wspomnianych pierwiastków w naszym środowisku. Celem badań było określenie, czy platan klonolistny (Platanus x acerifolia) może służyć jako bioindykator zanieczyszczeń powietrza. Drzewo to występuje prawie w całej Europie Środkowej, jest stosunkowo odporne na zanieczyszczenia środowiska, a jego cechą charakterystyczną jest zrzucanie kory. Przeprowadzone badania obejmowały opracowanie procedury analitycznej pozwalającej na analizę ilościową zawartości wytypowanych metali ciężkich: miedzi, cynku, żelaza, manganu, rtęci oraz dodatkowo siarki. Wyniki i poprawność stosowanej procedury przygotowania próbek kory do analizy potwierdzono badaniami materiału certyfikowanego (BCR-062 Olive leaves). Zwrócono szczególną uwagę na wpływ poszczególnych etapów przygotowania próbek (mycie, suszenie, rozdrabnianie itd.), co zwłaszcza w przypadku rtęci ma bardzo duże znaczenie z uwagi na jej dużą lotność. Ponadto przebadano próbki pochodzące z różnych części drzewa: konary, pień i korzenie. Kolejną zmienną były miejsca pobrania próbek, kora drzew rosnących przy ruchliwych ulicach, w parkach, pobrane w różnych miastach Polski i Europy. Całkowitą zawartość rtęci oznaczono, wykorzystując automatyczny analizator rtęci Merkury Analyzer MA-2. Pozostałe metale ciężkie oznaczono na spektrometrze emisyjnym z indukcyjnie sprzężoną plazmą VISTA - MPX firmy VARIAN

Determination of N-nitrosodiethanolamine in trolamine by GC-FID method

This study investigated the possibility of determination of N-nitrosodiethanolamine in triethanolamine by GC-FID methods. Triethanolamine is a component of many pharmaceuticals, including Lamiderm and Ketoprofen. According to the 5th European Pharmacopoeia, the maximum permissible concentration of N-nitrosodiethanolamine is 25 ppb. N-nitrosodiethanolamine is characterized by high volatility and low concentration in real samples. Thus, vacuum distillation was applied for the preconcentration of an analyte. Chromatographic separation was performed using a J&W Scientific DB-WAX (30 m x 0.251 mm; DF = 0.25 µm) capillary column. The method was linear from 8 ppb to 1 ppm (R2 = 0.9995). According to the definition of the International Union of Pure Applied Chemistry (IUPAC), the detection limit (S/N = 3) of the present method for N-nitrosodiethanolamine is 7 ppm. The proposed GC-FID method is an efficient method for the separation and quantitative determination of N-nitrosodiethanolamine

Chemical modification of silica surface by bonding ketoimine groups for SPE

The applicability of silica gels, modified with ketoimine groups, in solid-phase extraction was tested. The surface characteristics of the modified silica was determined by elemental analysis, NMR spectra for the solid phases (29Si CP MAS NMR), analysis of pore size distribution of the silica support, and nitrogen adsorptiondesorption. The newly proposed sorbents with ketoimine groups were used for extraction of endocrine-disruptor compounds, extracted from water and powder milk. The properties of the sorbents were compared with commercial C18 ones

Flame Retardant Additives Used for Polyurea-Based Elastomers—A Review

The growing interest in modern polymer materials has targeted research on complex plastic coatings and the possibilities of modifying their features and properties during manufacturing. Today’s modern coatings, including polyurea and polyurethane, are among the most modern developed resins. Compared to other polymer coatings, they are distinguished by their versatility, strength, and durability. They undoubtedly represent the next step in the evolution of coatings. Advances in coating technology have also led to the development of spray, injection, and roto-cast application equipment, improving polyurea-based elastomers’ performance. For many years, there has been much interest in increasing the flame resistance of polymers. This is dictated by safety considerations and the increasing requirements for the flammability of plastics, the area of application of which is growing every year. This text attempts to provide an overview of current research on flame retardant composites. Particular attention was paid to polyurea (PU) and polyurea-based hybrids and the application areas of polyurea coatings. The paper defines flame retardants, discusses how they work, and presents the types of flame retardants and the current trends of their usage in the production of plastics

Ocena zawartości tytanu w błonie śluzowej pokrywającej dwuetapowe wszczepy śródkostne

Widely used biomaterials, including titanium and its alloys, manifest a range of the physicochemical properties which determine the way they are exploited. According to the literature, titanium dental implants, considered biocompatible with the human body, under certain conditions, may cause inflammatory or allergic reactions. The aim of the study has been to evaluate the content of titanium in the mucosa covering two-stage intraosseous implants of the Osteoplant-Hex® system. The content of titanium ions in the examined samples containing segments of mucosa collected from those dental implants was determined with an inductively-coupled plasma emission spectrometer VISTA-MPX produced by VARIAN ICP. A diverse titanium content in the mucosa adjoining the implants has been revealed during their healing period. The determined concentration of titanium ranged from 0.00 to 122.59 μg g–1. As the conducted research suggests, such a wide range may result from differences in the implant location, sex and age of patients. Therefore, the authors tried to find a relationship between the results and those variables.Szeroko stosowane współcześnie biomateriały, w tym tytan i jego stopy, wykazują wiele cech i właściwości fizykochemicznych, które determinują sposób ich wykorzystania. Jak wynika z piśmiennictwa, wszczepy tytanowe stosowane w stomatologii, uważane za biokompatybilne z ustrojem, mogą w określonych warunkach wywoływać reakcje zapalne lub alergiczne. Celem pracy była ocena zawartości tytanu w błonie śluzowej pokrywającej dwuetapowe wszczepy śródkostne systemu Osteoplant-Hex®. Zawartość jonów tytanu w badanych próbkach zawierających wycinki błony śluzowej pobrane nad wszczepami stomatologicznymi oznaczono na spektrometrze emisyjnym z indukcyjnie sprzężoną plazmą VISTA-MPX firmy VARIAN ICP. Wykazano zróżnicowaną zawartość tytanu w błonie śluzowej kontaktującej się z implantami w okresie ich wgajania. Oznaczono stężenia tytanu od 0,0 do 122,59 μg g–1. Jak wynika z badań, duża rozpiętość wyników może być uzależniona od lokalizacji wszczepu, płci pacjentów, a także wieku, i dlatego podjęto próbę powiązania uzyskanych wyników z kilkoma potencjalnymi parametrami