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Adhesive Properties of Branched Oligoesters Plasticized with Triethyl Citrate and Drug Release from These Carriers
Dvořáková, Petra ; Šnejdrová, Eva (advisor) ; Mužíková, Jitka (referee)
CHARLES UNIVERSITY IN PRAGUE FACULTY OF PHARMACY IN HRADEC KRÁLOVÉ Department of Pharmaceutical Technology Rigorous Thesis Adhesive properties of branched oligoesters plasticized with triethyl citrate and drug release from these carriers Mgr. Petra Dvořáková SUMMARY The aim of this thesis was the study of adhesive properties of branched terpolymers of D,L-lactic acid, glycolic acid and dipentaerythritol, and release of fluconazole and aciclovir from these carriers. All tested carriers were plasticized with 30% of triethyl citrate (TEC). In the theoretical part of this thesis mechanisms of bioadhesion, biological substrates, polymers used in drug delivery systems and mechanisms of drug release are described. In the experimental part adhesivity of plasticized oligoesters was measured. Hydrated mucin isolated from porcine stomach was used as a model substrate for bioadhesion. The rate of adhesivity is the maximal force Fmax [N], which is required for the detachment of tested samples from the substrate. This force was related to the size of the contact surface and expressed in units mN/mm2 . The highest adhesivity was measured in oligoesters labelled 5D and 8D, which had low dynamic viscosity. However, it is impossible to state linear relationship between adhesivity and dynamic viscosity. The release of...
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A Study of the Properties of Tablets from two Types of Microcrystalline Cellulose
Lišková, Simona ; Šnejdrová, Eva (referee) ; Mužíková, Jitka (advisor)
The thesis studies mechanical strenght and disintegration time of tablets from two types of Microcel - Microcel® MC - 12 a Microcel® MC - 500. These characteristics were studied depending on compression force (3, 4 and 5 kN) and addition of two types of lubricants (magnesium stearate, natrium stearyl fumarate) in two concentrations - 0, 5 % and 1 % and addition of two model active substances in concentration 50 % (acetylsalicylic acid and ascorbic acid). For compression with active substance the compression force of 5 kN was used. It was found that tablets from Microcel® MC - 12 had higher mechanical strenght than the tablets from Microcel® MC - 500. The mechanical strenght was markedly lower by the addition of lubricants in tablets using both types of Microcel. Microcel® MC - 500 was more sensitive to addition of the lubricants. Sensitivity was as higher as the concentration of lubricant was stronger. Addition of magnesium stearate made tablets of lower compactability. Also disintegration time of both types of tablets was shorter with addition of lubricant. With using Microcel® MC - 12 disintegration time was a little longer. In the case of using Souhrn 86 magnesium stearate as a lubricant in the concentration of 1 % the disintegration time was the shortest. Tablets from Microcel® MC - 12 and with...
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A study of the properties of tablets made of dibasic calcium phosphate dihydrate.
Korotvičková, Martina ; Mužíková, Jitka (advisor) ; Šnejdrová, Eva (referee)
This thesis deals with the study of properties of the tablets from calcium hydrogen phosphate dihydrate (Emcompress® ) with Vivasol in concentration 1 or 2 % and lubricants, their concentration was 0,5 or 1 %. Then the properties of tablets from Emcompress with Prosolv in ratio 1:1 and 3:1 without or with 0,5 or 1 % of lubricants were studied. The lubricants were magnesium stearate and sodium stearyl fumarate (Pruv). The tablets with Vivasol were compressed with a force of 10, 12 and 14 kN, the others with a force of 6, 8 and 10 kN. The tensile strenght and the disintegration time were tested. Whereas tensile strenght of tablets with Vivasol was increased with increasing compression force, independently on concentration or type of lubricant, the disintegration time did not increase with compression force and it was shorter with increasing concentration of Vivasol, mainly when magnesium stearat was added. The tensile strenght of tablets from Emcompress-Prosolv 1:1 was higher than of tablets from Emcompress-Prosolv 3:1 and it incereased with compression force. The lubricants decreased tensile strenght much more for tablets from Emcompress-Prosolv 1:1 directly proportional with increasing concentration of lubricants. The shortest disintegration time had the tablets from mixture of dry binders, without...
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A study of the properties of tablets made of three types of microcrystalline cellulose.
Koreňová, Michaela ; Mužíková, Jitka (advisor) ; Šklubalová, Zdeňka (referee)
THE STUDY OF TABLETS' PROPERTIES FROM THREE TYPES OF MICROCRYSTALLINE CELLULOSE SUMMARY The thesis deals with the study of properties of tablets from three type of directly compressible microcrystalline cellulose, namely Microcel® MC-102 SP, Microcel® MC-122 and Microcel® MC-250. The focus of the study was the dependence of tensile strength and disintegration time of the tablets on the compression force, the addition of 0,5% lubricants, namely magnesium stearate and sodium stearyl fumarate (Pruv), and addition of 50% model drugs, namely acetylsalicylic acid and ascorbic acid. The compression forces were used 3, 4 and 5 kN, compacts containing the drugs were compressed only with a force of 5 kN. The strength of tablets from all three types Microcels increased with increasing compression force, the presence of the lubricant resulted in a decrease in the strength. The compacts of Microcel MC-102 SP had similar tensile strenght like the compacts of Microcel MC-122, while the tensile strenght of compacts of Microcel MC-250 was lower. The greatest and smallest decline of tensile strenght due to the lubricant effect was recorded for Microcel MC-122 and Microcel MC-102 SP respectively. The lubricants shortened disintegration time of all Microcels. The longest disintegration time had the tablets of Microcel MC-102...
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A study of the properties of tablets made of directly compressible sorbitol.
Zemanová, Eva ; Mužíková, Jitka (advisor) ; Šnejdrová, Eva (referee)
A study of the properties of tablets made of directly compressible sorbitol. SUMMARY : The thesis deals with the study of the properties of tablets from two types of directly compressible sorbitol, namely SorbitabTM SD 250 a SorbitabTM SD 500. The focus of the study was the dependence of the tensile strength and disintegration time of the tablets on the compression force, the addition of lubricants magnesium stearate and sodium stearyl fumarate (Pruv ), with concentrations of 0,5% and 1% and a 50% addition of model active ingredients, namely acetylsalicylic acid and ascorbic acid. The compression forces were used 3, 4,5 and 6 kN; tablets containing the drugs were compressed only with a force of 6 kN. The tensile strength of tablets from SorbitabTM SD 500 was higher than of tablets from SorbitabTM SD 250. SorbitabTM SD 500 has demonstrated sensitivity to addition of both lubricants in both concentrations, unlike SorbitabTM SD 250, when the tensile strength of tablets decreased only with the addition of 1% magnesium stearate. The disintegration time of tablets was prolonged by the lubricants, in the case of tablets with SorbitabTM SD 500 most with 1% magnesium stearate at all compression forces. Higher tensile strength was found for tablets containing acetylsalicylic acid and for both drugs with SorbitabTM...
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The study of the properties of tablets made from the mixtures of directly compressible starch and lactitol.
Vajglová, Jana ; Mužíková, Jitka (advisor) ; Šnejdrová, Eva (referee)
The work studied the mechanical strenght and the disintegration time of tablets prepared by direct compession of mixtures of pregelatinized starch Starch 1500 and directly compresible lactitol LactyTab in proportion 1:1 and 3:1 according to the compression force (12, 16, 20kN), concentration of the lubricant, sodium stearyl fumarate, Pruv, (0, 0,5 and 1%) and addition of model active substance, acetylsalicylic acid (50%). The tablet strenght of the mixtures of Starch 1500 and lactitol in proportions 1:1 and 3:1 rose with the compression force and decreased with increasing concentration of Pruv, there was no significant difference between the strenght of the compacts with 0,5 and 1% of the lubricant for the mixture in proportion 1:1. The blend of Starch 1500 and lactitol 1:1 without any lubricant gave the firmest tablets. Similarly, the mixture in proportion 1:1 with acetylsalicylic acid showed higher strenght of the compacts which decreased with increasing concentration of Pruv. The disintegration time of the compacts rose with the compression force. The hypothesis of longer disintegration time of the tablets with bigger amount of Starch 1500 was confirmed at compression force 12 and 20kN with an exception to blends containing 1% of Pruv. The tablets including acetylsalicylic acid showed longer...
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A study of the properties of tablets from the mixture of directly compressible xylitol and microcrystalline cellulose.
Komínková, Hana ; Mužíková, Jitka (advisor) ; Šnejdrová, Eva (referee)
Název v anglictine: A study of the properties of tablets from the mixture of directly compressible xylitol and microcrystalline cellulose. Summary: The thesis deals with the study of properties of tablets from a mixture of directly compressible xylitol, namely Xylitab® 300, and microcrystalline cellulose, namely Microcel® MC-12, in the ratio of 1:1. (This ratio was arrived at after preceding experiments concerning the strength of tablets made only from Xylitab® 300, and from a mixture of Xylitab® 300 and Microcel® MC-12 in the ratio of 3:1. The strength was insufficient in these cases.) The focus of the study was the dependence of the tensile strength and disintegration time of the tablets on the compression force, the addition of lubricants, namely magnesium stearate and sodium stearyl fumarate (Pruv®), with concentrations of 0.5% and 1%, and a 50% addition of model active ingredients, namely acetylsalicylic acid and ascorbic acid. The compression forces used were 10, 12.5, and 15 kN; tablets containing the drugs were only compressed with a force of 15 kN. Tablets with a weight of 0.5 g and a diameter of 13 mm were compressed using material testing machine T1-FRO 50 TH.A1K Zwick/Roell and they were further subjected to a strength test using Schleuniger Tablet Tester 8M and to a disintegration time test...
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A Study of the Properties of Compacts from silicified microcrystalline celluloses.
Nováková, Petra ; Mužíková, Jitka (advisor) ; Šnejdrová, Eva (referee)
V práci je studována pevnost tablet v tahu a doba rozpadu výlisků ze silicifikovaných mikrokrystalických celulos, Prosolv SMCC 90 a Prosolv HD 90, v závislosti na lisovací síle, přídavku dvou typů mazadel a dvou léčivých látek. Mazadla byla stearan hořečnatý a stearylfumarát sodný v koncentraci 0,5%, aktivní látky kyselina askorbová a acetylsalicylová v koncentraci 50%. Prosolv SMCC 90 byl lépe lisovatelný než Prosolv HD 90; výlisky měly vyšší pevnost a ta se zvyšovala s lisovací silou. Prosolv HD 90 byl více citlivý na přídavek mazadel a větší pokles pevnosti byl zaznamenán v přítomnosti stearylfumarátu sodného. Vliv mazadel na pevnost tablet v přítomnosti léčivých látek nebyla stejná. Doba rozpadu výlisků z Prosolvu HD 90 bez i s mazadly byla kratší než z Prosolvu SMCC 90 a zvyšovala se s rostoucí lisovací silou. Doba rozpadu se prodloužila přídavkem mazadel a významně byla zkrácena přídavkem léčivých látek. Výlisky s kyselinou askorbovou měly kratší dobu rozpadu než s kyselinou acetylsalicylovou a doba rozpadu nebyla výrazně ovlivněna přítomností mazadel.
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Study of bioadhezive polymers
Kuntová, Darina ; Šnejdrová, Eva (advisor) ; Mužíková, Jitka (referee)
DIPLOMA THESIS 2006 DARINA KUNTOVÁ The aim of this graduation theses was to study the adhesiveness of oligoesters branched using mannitol or dipentaerythritol and plasticized 20% of ethyl pyruvate or 30% trietyl citrate under various testing conditions using Material testing machine Zwick/Roel T1-FR050TH.A1K. The maximum force (Fmax) required to detaching the polymer systems from substrate was measured for determination of adhesiveness of oligoesters. The detachmen speed of 10 mm/min, 100 mm/min and 200 mm/min, consolidation time of 5s or 10s and contact force 10N or 20 N were tested. It was found that Fmax of branched oligoesters was significantly higher in comparison with cellulose derivatives, acrylate derivatives or gelatine. The increase of the maximal adhesive force is due to the growing consolidation force, the contact time and sample detachment velocity.
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