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Nowe rozwiązania i modyfikacje najpopularniejszych polimerowych nośników substancji aktywnych

Odrobińska Justyna, Neugebauer Dorota

Wiadomości Chemiczne

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2019

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[Z] 73, 9-10

481--501

EN

The progress of medicine and cosmetology corresponds to the increase in the need for new drug design and delivery methods, due to the already common cancer risk, as well as other diseases, which are still difficult for curing. Regardless of the type of active substance and its final application, the selection and synthesis of the appropriate carrier is crucial to provide the pharmaceutics to the target with the controlled release for a set period of time, including the intelligent activity. Depending on the way the bioactive substance is bound to carriers in the drug delivery systems (DDS) they are classified onto: carriers that physically encapsulate them inside i.e. liposomes, solid lipid nanoparticles, nanostructural lipid carriers, nanoparticles (nanocapsules, nanospheres), micelles, and carriers that chemically bind the active substance, i.e. conjugates, polyplexes. The current studies are emphasized to achieve the most perfect improvement, which concerns the efficiency of encapsulation, the ability to deliver several compounds simultaneously or sequentially, the productive release, the elimination of side products, the replacement of synthetic polymers by natural, biodegradable, biocompatible and non-toxic polymers. These carriers are also developed in terms of sensitivity to stimuli (one or several simultaneously or sequentially activated) and adapted for combined therapy. Although the subject of active substance delivery with the use of carriers is already widely studied, these are still a needs for the designing of new or the enhancement of the already known DDS. Working on this issue there is hope that today still incurable diseases, neoplastic diseases, as well as the diagnosis of these diseases themselves, will be possible to control and treat in the future. This report presents the current state of the knowledge in the area of DDS, focusing on newly developed solutions in the last years.

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Krytyczne stężenie micelarne i metody jego wyznaczania

Piotrowska-Kirschling A., Drzeżdżon J., Chmurzyński L., Jacewicz D.

Wiadomości Chemiczne

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2018

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[Z] 72, 11-12

815--828

EN

Surfactants are substances, which have surface activity in aqueous solutions [1–3]. By adsorbing on the surface (boundary of phase separation) of the system, they change the surfactant properties of the liquid. Surfactants consist of a hydrophobic part (non-polar, called “tail”) and a hydrophilic part (polar, called “head”) [1–3]. The overall structure of the surfactant molecule is shown in Figure 1. In aqueous solution after exceeding one critical micellar concentration of the CMC surfatant (Critical Micelle Concentration), the surfactant molecules aggregate to form micelles [1–5]. Knowledge of CMC values and the micelle formation in solution, it determines the properties of surfactants and their subsequent use in the chemical industry. Surfactants are used in the chemical industry, inter alia, for the production of many detergents, cosmetics, paints, dyes, agrochemicals, pharmaceuticals, food or oil [2, 3].

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Polimery wykazujące samoorganizację makrocząsteczek jako systemy kontrolowanego uwalniania leków

El Fray M., Gajowy J.

Polimery

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2012

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T. 57, nr 4

257-265

PL

Artykuł stanowi przegląd literaturowy dotyczący polimerów wykazujących samoorganizację makrocząsteczek — interesującej grupy materiałów o różnorodnych właściwościach i zastosowaniach, zwłaszcza medycznych — wykorzystywanych jako systemy kontrolowanego uwalniania leków. Spontaniczne grupowanie się makrocząsteczek w roztworach prowadzi do tworzenia się różnych struktur, takich jak: micele, mikro/nanosfery lub polimerosomy, w efekcie występowania pomiędzy określonymi fragmentami makrocząsteczek słabych wiązań i oddziaływań, tj. wiązań wodorowych oraz oddziaływań van der Waalsa, elektrostatycznych lub hydrofobowych. Przedstawiono wybrane formy strukturalne powstające w wyniku samoorganizacji makrocząsteczek w roztworach (wodnych i organicznych). Scharakteryzowano polimery zdolne do tworzenia takich struktur, metody ich otrzymywania oraz przykłady zastosowań w medycynie w charakterze systemów kontrolowanego uwalniania leków.

EN

The paper is a literature review concerning the polymers capable of macromolecular self-assembly — an interesting group of materials possessing diverse properties, which found various, especially medical applications, as controlled release drug delivery systems. Spontaneous assembly of macromolecules in solutions leads to the formation of various structural forms such as micelles, micro/nanospheres or polymersomes, as a result of the presence of weak bonds and interactions, i.e. hydrogen bonds as well as van der Waals, electrostatic or hydrophobic interactions, between specific parts of macromolecules. Selected structural patterns formed by self-assembly of macromolecules in organic and aqueous solutions were presented. The polymers capable of forming self-assembled structures, methods of their synthesis as well as the examples of medical applications as drug delivery systems have been described.

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Acoustical Spectroscopy of Carbohydrate Aqueous Solutions: Saccharides; Alkyl Glycosides; Cyclodextrins. Part II. Association and Complexation

Kaatze U.

Archives of Acoustics

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2010

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Vol. 35, No. 4

739-762

EN

Results from broadband acoustical spectroscopy for aqueous solutions of mono- and disaccharides with salts added, of various alkyl glycosides, and of α-cyclodextrin with n-octyl-β-D-glucopyranoside added are briefly summarized in view of their relevance in the study of molecular association and complexation processes. Mono- and tridentate complexes of alkali earth ions with saccharides are discussed as well as the monomer exchange between micellar structures and the suspending phase in the alkyl glycoside surfactant solutions. Particular attention is given to the behaviour at solute concentrations close to the critical micelle concentration or aggregate concentration, respectively. Also described is the competition between inclusion complex formation and self-aggregation in solutions containing cyclodextrin and alkyl glycoside surfactant.

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The Miscibility of Sodium Dodecyl Sulfonate with Anionic, Nonionic and Cationic Surfactants in Mixed Monolayers and Micelles

Wydro P.

Polish Journal of Chemistry

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2007

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Vol. 81, nr 12

2157-2169

EN

The surface properties of sodium dodecyl sulfonate (SDSn), dodecyl-b-D-glucoside (DG), dodecyltrihydroxyethylammonium bro mide (DTEAB) and sodium dodecyl sul fate (SDS) and their mixtures: SDSn/SDS, SDSn/DG and SDSn/DTEAB were studied. The miscibility and the composition of the mixed monolayers and micelles as well as the interactions between their components were analyzed with the Motomura theory. It was found that among the investigated mixed systems the best surface properties reveal the anionic-cationic mixtures. Moreover, the investigated systems mix nonideally both in the monolayers and micelles. The magnitude of the deviations from ideal behaviour increases in the order: an ionic/an ionic < an ionic/nonionic << an ionic/cationic. Both the mixed monolayers and mi celles formed from SDSn/SDS and SDSn/DG mix tures are richer, as compared to the mixed solutions, in the more surface-active component, while the mixed monolayers and micelles formed from cationic/anionic mixtures (SDSn/DTEAB) possess more symmetrical composition than the mixed solution. As it was found the interactions between molecules both in the mixed monolayers and micelles are more attractive or less repulsive as compared to those in respective one-component monolayers and micelles and the strength of these interactions increases in the order: SDSn/SDS < SDSn/DG < SDSn/DTEAB.

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Electrochemical Behavior of Ascorbic Acid and Uric Acid in the Presence of Micelles and Their Selective Determination Application

Gao Z., Peng J., Han X.

Polish Journal of Chemistry

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2007

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Vol. 81, nr 3

441-454

EN

The electrochemical behavior of ascorbic acid (AA) and uric acid (UA) in both aqueous cetylpyridinium bromide (CPB) and sodium dodecyl benzene sulfonate (SDBS) micellar solutions have been studied by cyclic voltammetry. The oxidation peak potentials shift more negatively, and the peak currents increase in aqueous CPB micellar solutions for AA and UA. However, the oxidation peak potentials shift more positively, and the peak currents decrease in aqueous SDBS micellar solutions for AA and UA. Therefore, CPB can enhance the electrochemical oxidation reaction for AA and UA, and SDBS hinders the electrochemical oxidation reaction. The electrochemical kinetic parameters for AA and UA in both aqueous CPB and SDBS micellar solutions are determined by chronocoulometry (CC) and chronoamperometry (CA). The charge transfer coefficients _ and the electrode reaction rate constants kf for AA and UA are enhanced in aqueous CPB micellar solutions, but reduced in aqueous SDBS micellar solutions. The pulse differential voltammetric behavior for AAand UAare also investigated in this work. The experimental results show that the oxidation peak potentials forAAandUAare separated by 270mVin the presence ofCPB in aqueous PBS (phosphate buffer solution, pH 6.8) solutions. Thus, AA and UA can be selectively determined in aqueous CPB micellar solutions, especially selectively determination of UA in the presence of excess of AA is possible. According to our work, the practical application of the results can be used to determineUAin human urine and serum samples, the determination results are satisfied.

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Water soluble amphiphilic polymers

Shtilman M.I., Kuskov A.N., Tashmuhamedov R.I., Torchilin V.P., Tsatsakis A.M.

Prace Naukowe Instytutu Technologii Organicznej i Tworzyw Sztucznych Politechniki Wrocławskiej. Konferencje

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2003

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Vol. 52, nr 25

202-202

EN

Water soluble amphiphilic polymers of poly-N-vinylpyrrolidone (PVP) and polyacrylamide (PAA) were synthesized by radical polymerization in the presence of functional mercaptane and introduction of one end heptadecyl or octadecyl group. Polymers form micelles in water solution Polymers were found to be efficient steric protectors of liposomes in vitro and in vivo.