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EN
Suppositories with cocoa butter containing dehydroepiandrosterone (DHEA) without and with the addition of Span 80 and Tween 80 as surfactants with low and high HLB values were prepared. The physical properties and the drug content of all prepared suppositories were in accordance with the pharmacopoeial requirements. The release study tests in three dissolution media such as water, lactic acid solution at pH 4.2 and phosphate buffer at pH 7.4 were carried out. In acidic and alkalic media only about 10% and 27% of DHEA were released, respectively. The addition of Span 80 to the suppository mass did not improve the release process, but the addition of Tween 80 caused the increase in the amount of DHEA released in the acidic medium to about 35%. The data showed that rectal administration of suppositories with DHEA based on cocoa butter caused about 30% availability and after vaginal administration, only topical activity can be expected. By the addition of Tween 80 to the suppository mass availability of DHEA of about 35% from vaginal suppositories can be achieved.
EN
Due to continued interest in biodegradable polymers, chitosan is one of the most commonly used polymers in the field of control release of active substances. Currently as carriers of drugs, among tablets, or micro spheres transdermal systems, called films, are used. The presented results apply to study a drug release in buffer of pH = 7.2 from chitosan film. To study the kinetics of controlled release salicylic acid was used as a model substance. Obtained films were cross-linked in TPP solution and were also modified by applying outsider layer to slow down the release process. Received transdermal systems were tested with swelling kinetics and the release kinetics of salicylic acid. The obtained systems were tested in relation to different temperature of cross-linking solution of chitosan, different thickness of studied matrices, the influence of outside layer and varying initial amount of salicylic acid.
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EN
This minireview presents an overview of current knowledge on virion structure, genome organization and basic events in the development of influenza A virus. The processes of entry, transcription/replication and viral release are described. In this context, the roles of viral proteins (including recently discovered minor polypeptides) in the subsequent stages of viral development are also discussed.
EN
The aim of this paper was to prepare chitosan microspheres characterised by a narrow dispersion of dimensions, suitable for application for drug delivery systems (DDS). The materials, unmodified as well as functionalised using polyethyleneimine were then used for encapsulation of drug-mimicking dyes. The polymeric beads were prepared by one stage process of membrane emulsification. The encapsulation and then evaluation of the release of an active component was carried out using two cytostatics-mimicking dyes: methyl orange and Congo red. The efficiency of encapsulation changed with a type of microspheres and the type of a dye. The highest sorption towards dyes was revealed by PEI-modified chitosan microspheres. Methyl orange was released with the better efficiency than Congo red from all types of microspheres.
EN
BACKGROUND Semi-solid preparations for the skin are very popular. Bases affecting the release of active substances are the main component of this group of preparations. Among dermal formulations, a large percentage are those that contain non-steroidal anti-inflammatory drugs, including diclophenac sodium. Unfortunately, the permeation of diclofenac sodium through the skin is negligible, hence, numerous studies are conducted on its pharmaceutical availability. AIM OF THE STUDY The aim of the study was to assess the impact of the base on the release of diclophenac sodium from semi-solid dermal preparations. The following types of bases have been analyzed: gel-type, lipophilic, absorption and emulsion. MATERIAL AND METHODS The study compared two commercial preparations: Veral and Diclac Lipogel, and five formulations prepared with a prescription blender. The pharmaceutical availability of diclophenac sodium was examined using Kerckhoffs and Huizing apparatus. The release of diclophenac sodium was carried out at 37°C and 32°C. The absorbance of the samples was measured spectrophotometrically. RESULTS The ointment formulation based on glycerol possessed optimum pharmaceutical availability, which showed a high percentage of released diclofenac sodium, a high velocity release constant (k) and a low half-time release (t1/2). The least suitable bases for diclophenac sodium were the lipophilic vehicle – Vaseline and the absorption medium – eucerine. The pharmacokinetic parameters obtained from the glycerol ointment proved to be more advantageous than those from the gels based on carbopol. The kinetics of the other drugs turned out to be less fa-vorable than for the commercial gels. Faster and greater release of diclophenac sodium occurred at 37°C. CONCLUSIONS The study showed that the best release of diclofenac sodium was observed in the case of the prescription formulation (glycerol ointment), even compared to the commercially available preparations. The temperature influenced the amount and rate of diclofenac sodium released from the two analyzed gels.
PL
WSTĘP Półstałe preparaty na skórę cieszą się dużym zainteresowaniem. Podstawowym ich komponentem są podłoża mające wpływ na uwalnianie substancji czynnych. Wśród preparatów podawanych na skórę duży procent stanowią te, które zawierają niesteroidowe leki przeciwzapalne, w tym diklofenak sodu. Niestety, przenikanie diklofenaku sodu przez skórę jest niewielkie, stąd prowadzone są liczne badania nad jego dostępnością farmaceutyczną. CEL PRACY Celem pracy była ocena wpływu zastosowanego podłoża na uwalnianie diklofenaku sodu z półstałych preparatów podawanych na skórę. Analizie poddano podłoża typu żelowego, podłoże lipofilowe, absorpcyjne oraz podłoża emulsyjne. MATERIAŁ I METODY W pracy porównywano preparaty gotowe Veral i Diclac Lipogel oraz pięć preparatów wykonanych przy użyciu miksera recepturowego. Dostępność farmaceutyczną diklofenaku sodu zbadano aparatem Kerckhoffsa i Huizinga. Uwalnianie diklofenaku sodu przeprowadzono w temperaturze 37°C oraz 32°C. Absorbancję pobranych próbek mierzono spektrofotometrycznie. WYNIKI Optymalną dostępność farmaceutyczną miał preparat na bazie maści glicerolowej, który wykazywał wysoki procent uwolnionego diklofenaku sodu, wysoką stałą szybkości uwalniania k i niski czas połowicznego uwalniania t1/2. Podłożami najmniej odpowiednimi dla diklofenaku sodu okazały się podłoże lipofilowe – wazelina, oraz absorpcyjne – euceryna. Parametry farmakokinetyczne uzyskane z udziałem maści glicerolowej okazały się korzystniejsze niż parametry uzyskane z gotowych żeli na bazie carbopolu. Kinetyka pozostałych preparatów okazała się mniej korzystna niż gotowych żeli. Większe i szybsze uwalnianie diklofenaku sodu następowało w temperaturze 37°C. WNIOSKI Przeprowadzone badania wykazały, że diklofenak sodu najlepiej uwalniał się z preparatu recepturowego (maść glicerolowa), nawet w porównaniu z komercyjnie dostępnymi preparatami. Podłożami najmniej odpowiednimi okazały się wazelina i euceryna. Temperatura badania wpływała na ilość i szybkość uwolnionego diklofenaku sodu z dwóch badanych żeli.
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