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1

VAPOUR PERMEATION STUDY OF WATER AND ETHANOL THROUGH CROSSLINKED CHITOSAN AND ALGINATE MEMBRANES

100%

Turczyn R., Gnus M., Dudek G., Tórz A., Łącka D., Strzelewicz A., Łapkowski M.

Progress on Chemistry and Application of Chitin and its Derivatives

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2015

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vol. 20

281-288

EN

A vapour permeation of water and ethanol through homogenous chitosan and alginate membranes was investigated. The influence of the polymer matrix and crosslinking agents, and measurement protocol on the transport properties were discussed. The conducted experiments showed the greater separation factor, better stability and resistant to solvents for chemically crosslinked membranes. On the other hand, stronger association of the matrix, than the physical, caused decrease of vapour fluxes.

2

MECHANISM OF WATER DIFFUSION INTO NONCROSSLINKED AND IONICALLY CROSSLINKED CHITOSAN MEMBRANES

88%

Gierszewska-Drużyńska M., Ostrowska-Czubenko J.

Progress on Chemistry and Application of Chitin and its Derivatives

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2012

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vol. 17

63 - 70

EN

Ionically crosslinked chitosan membranes were prepared and their swelling behaviour was analysed. Low‑molecular pentasodium tripolyphosphate (TPP) and/or high‑molecular sodium alginate (NaAlg) were used as ionic crosslinkers. Dynamic swelling of noncrosslinked (Ch) as well as singly (Ch/TPP, Ch/NaAlg) and doubly (Ch/NaAlg/TPP) crosslinked chitosan membranes was performed in buffered aqueous solutions of various pH to determine the mechanism of water diffusion into these hydrogels. It was stated out that mechanism of water diffusion into studied chitosan hydrogel membranes depends both on pH of swelling solution as well as on the type of membrane (type of crosslinker). The water transport mechanism was determined to be: i) Fickian or ‘Less Fickian’ diffusion, ii) non‑Fickian diffusion (anomalous diffusion) and iii) Case II or Super Case II diffusion.

3

PERVAPORATIVE INVESTIGATION OF ETHYL ALCOHOL DEHYDRATION

88%

Gnus M., Dudek G., Turczyn R., Tórz A., Łącka D., Konieczny K., Łapkowski M.

Progress on Chemistry and Application of Chitin and its Derivatives

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2015

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vol. 20

54-63

EN

Pervaporative separation properties of crosslinked chitosan and alginate membrane on ethanol-water mixture at room temperature was studied. The influence of crosslinking agents on the separation properties were discussed. Selected crosslinking agents were affected differently on used polymer matrices. The better separation properties were obtained for membranes crosslinked by phosphoric (V) acid. The highest pervaporation separation index (309.6 kg/m2·h) and separation factor (52.6) were obtained for phosphoric (V) acid crosslinked alginate membranes, however, the greatest total flux (12.4 kg/m2·h) obtained for phosphoric acid crosslinked chitosan membranes

4

Controlled release formulations of atrazine produced by tumbling agglomeration

75%

Małyszka T., Jankowski T.

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issue 3

5

HYDROGEL ANTIBACTERIAL COATING FOR SILICONE MEDICAL DEVICES

75%

Kopeć K., Żuk M., Ciach T.

Progress on Chemistry and Application of Chitin and its Derivatives

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2021

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vol. 26

135-147

EN

Effective antibacterial coatings are in demand in medicine, especially for urological medical devices such as catheters and stents. We propose the production method of an antibacterial hydrogel coating on polydimethylsiloxane (PDMS, silicone), a popular surface for medical materials. The coating process consists of the following steps: PDMS surface activation (introduction of hydroxyl groups), silanisation (introduction of amine groups) and application of chitosan/alginate hydrogel with the addition of lysozyme as an antibacterial agent using the layer-by-layer method. We investigated the effect of polyion concentration on the coating mass, swelling ratio and stability. We analysed the adsorption of Micrococcus luteus, Escherichia coli and Proteus rettgeri on a PDMS surface using confocal laser scanning microscopy. The chitosan/alginate hydrogel coating with immobilised lysozyme protected the PDMS surface against adhesion for all three tested bacterial strains.

6

CHARACTERISTICS OF ASCORBIC ACID RELEASE FROM TPP-CROSSLINKED CHITOSAN/ALGINATE POLYELECTROLYTE COMPLEX MEMBRANES

75%

Gierszewska M., Ostrowska-Czubenko J., Chrzanowska E.

Progress on Chemistry and Application of Chitin and its Derivatives

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2018

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vol. 23

76 - 87

EN

Chitosan/alginate polyelectrolyte complex membranes (Ch/Alg) additionally cross-linked with tripolyphosphate (TPP) and containing ascorbic acid (AA) were prepared. The dynamic swelling behaviour of Ch/Alg/TPP and ascorbic acid release from the membrane were characterised in different buffer solutions. It has been found that the pH of the buffer solution affects the swelling and release behaviour of AA. Ascorbic acid release, observed over a period of 360 min, exhibited a biphasic pattern, characterised by a fast initial burst release, followed by a slow, sustained release. Different mathematical models were used to study the kinetics and transport mechanism of AA from Ch/Alg/TPP hydrogels. Drug release data were fitted to the zero order kinetic model and first order kinetic model. To characterise the drug mechanism, the release data were fitted to the Higuchi and Korsmeyer-Peppas equations. The initial burst AA release followed zero order kinetics and was quasi-Fickian in nature. The second step of AA release followed first order kinetics.

7

The use of alginate impression material for the controlled release of sodium fusidate

75%

Czarnecka B., Nicholson J. W.

Dental Forum

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2013

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vol. 41

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issue 2

11-14

EN

Introduction. Alginate impression material has the potential to act as a controlled release material, either for transmucosal drug delivery, or for use as a self-disinfecting impression material in clinical dentistry. Aim of the study. To study whether sodium fusidate could be released from alginate impression material and, if so, to determine the release kinetics. Material and methods. Sodium fusidate was incorporated into alginate impression material at the mixing stage (2% by mass). The mixed material was pressed into a sheet and, once cured, discs (6 mm diameter x 2 mm thick) were cut out, and stored in water, one disc in a 5 ml volume. Small samples (20 μl) were withdrawn at time intervals of 1, 2, 3, 4, 5, 24 h, 1, 2 and 3 weeks and analysed by HPLC. Results. Sodium fusidate was released from the impression material in a process that was shown to be diffusion based for the first 5 hours or so. The diffusion coefficient was 2.25 x 10-5 cm2 s-1, and the release corresponded to 36.0 ± 1.0% of the total loading. The system thus shows promise for clinical application.

PL

Wstęp. Alginatowe masy wyciskowe mogą być potencjalnie użyte jako materiały służące do kontrolowanego uwalniania, np. leków wchłanianych przez błonę śluzową czy środków dezynfekcyjnych, które umożliwiałyby autodezynfekcję wycisków w warunkach klinicznych. Cel pracy. Ocena czy fusydan sodu może być wydzielany z alginatowych mas wyciskowych oraz ocena kinetyki wydzielania. Materiał i metody. Fusydan sodu wprowadzono podczas mieszania do alginatowej masy wyciskowej w proporcji 2% masowych. Z zamieszanego materiału uformowano cienką warstwę, po związaniu wycięto próbki w kształcie krążka (6 mm średnicy x 2 mm grubości), każdą próbkę przechowywano oddzielnie w 5 ml wody. Po upływie kolejno 1, 2, 3, 4, 5, i 24 godzin a następnie 1, 2 i 3 tygodni pobierano niewielkie ilości roztworu, który poddawano analizie w HPLC. Wyniki. Fusydan sodu w ciągu pierwszych 5 godzin był wydzielany z masy wyciskowej w procesie dyfuzji. Współczynnik dyfuzji wynosił 2.25 x 10-5 cm2 s-1, wydzielona ilość odpowiadała 36.0 ± 1.0%. W związku z tym ten system wydaje się być obiecujący w warunkach klinicznych.

8

FUNCTIONAL THREE-COMPONENT POLYMERIC BIOCOMPOSITES FOR THE TREATMENT OF BEDSORES

75%

Wiśniewska-Wrona M., El Fray M.

Progress on Chemistry and Application of Chitin and its Derivatives

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2018

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vol. 23

185 - 206

EN

Presented here are the results of investigations into the preparation of three-component dressing materials from various biopolymers in the form of a single-layer film which is suitable as a carrier for pain-relieving (lidocaine) and bacteriostatic (sulphanilamid) therapeutic agents. Physical-chemical, biological and usable properties of the prepared materials were tested and assessed. The amount of added active substance was adopted based on the dose recommended by the Polish Pharmacopeia for external medicinal preparations. Antibacterial activity against gram (-) Escherichia coli and gram (+) Staphylococcus aureus was assessed in some of the biocomposites by quantitative methods. The cytotoxic action in direct contact with the mouse fibroblast NCTC clone 929 was also estimated. Thermal analysis (DSC), infrared spectrophotometry (FTIR) and nuclear magnetic resonance spectroscopy were employed to investigate the impact of the variable contents of chitosan, alginate, carboxymethyl cellulose (CMC), and the active substance upon the chemical- and phase-structure of the prepared three-component polymeric biocomposites. It was found that the quantitative composition of the biocomposites and the additive of active substances lidocaine and sulphanilamide exert a vital impact upon their physical-mechanical and usable properties (imbibition, absorption). Investigations into the release of the medicinal substance from the investigated biocomposites to an acceptor fluid led to the conclusion that the kinetics of the process may be described by a complex first order rate equation with two exponential functions.

9

Otrzymywanie włókien alginianowych i chitozanowych metodą elektroprzędzenia

63%

Michna J., Irusta S., Kyzioł A.

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EN

Electrospinning is a simple and efficient method of polymer fibers fabrication. In this method electrostatic forces are used to obtain fibers or particles with different morphology and size from micro- to nanometers. Nowadays more than 100 polymers, natural or synthetic ones, have been successfully electrospun into fibers. Electrospinning process is affected by various different parameters such as viscosity, polymer’s average molecular mass, voltage, flow rate, etc. Electrospinning of biopolymers, alginate and chitosan, is difficult. Both of these polymers are non-toxic, biodegradable and possess antibacterial properties, all these properties are desirable in biomedical applications. In the presented work an influence of parameters of electrospinning on process of obtaining of alginate and chitosan fibers was presented and discussed. Alginate fibers were obtained with poly(ethylene oxide), while chitosan fibers were prepared from trifluoroacetic acid and dichloromethane solution.

PL

Elektroprzędzenie (ang. electrospinning) jest prostą i efektywną techniką pozwalającą na produkcję włókien polimerowych. W metodzie elektroprzędzenia siły elektrostatyczne są używane do produkcji włókien lub sfer o różnej morfologii i rozmiarach w skali mikro- i nanometrów. Obecnie ponad 100 polimerów, naturalnych i syntetycznych, zostało z powodzeniem wytworzonych w procesie elektroprzędzenia. Na proces elektroprzędzenia wpływa wiele parametrów, między innymi lepkość roztworu, średnia masa cząsteczkowa polimeru, przyłożone napięcie, prędkość przepływu. Elektroprzędzenie biopolimerów, alginianu i chitozanu jest wyzwaniem. Te dwa naturalne polimery charakteryzują się niską toksycznością, biodegradowalnością i właściwościami antybakteryjnymi, co jest szeroko wykorzystywane i pożądane w aplikacjach biomedycznych. W prezentowanej pracy omówiono wpływ warunków elektroprzędzenia na proces otrzymywania włókien alginianowych domieszkowanych poli(tlenkiem etylenu) i włókien chitozanowych otrzymywanych z roztworu kwasu trifluorooctowego i dichlorometanu.

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VAPOUR PERMEATION STUDY OF WATER AND ETHANOL THROUGH CROSSLINKED CHITOSAN AND ALGINATE MEMBRANES

MECHANISM OF WATER DIFFUSION INTO NONCROSSLINKED AND IONICALLY CROSSLINKED CHITOSAN MEMBRANES

PERVAPORATIVE INVESTIGATION OF ETHYL ALCOHOL DEHYDRATION

Controlled release formulations of atrazine produced by tumbling agglomeration

HYDROGEL ANTIBACTERIAL COATING FOR SILICONE MEDICAL DEVICES

CHARACTERISTICS OF ASCORBIC ACID RELEASE FROM TPP-CROSSLINKED CHITOSAN/ALGINATE POLYELECTROLYTE COMPLEX MEMBRANES

The use of alginate impression material for the controlled release of sodium fusidate

FUNCTIONAL THREE-COMPONENT POLYMERIC BIOCOMPOSITES FOR THE TREATMENT OF BEDSORES

Otrzymywanie włókien alginianowych i chitozanowych metodą elektroprzędzenia