energy profile of compression
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Eighth edition xxiii, 615 stran : ilustrace, tabulky ; 28 cm
- MeSH
- nádory radioterapie MeSH
- nukleární lékařství metody MeSH
- radioterapie metody MeSH
- Publikační typ
- učebnice MeSH
- Konspekt
- Učební osnovy. Vyučovací předměty. Učebnice
- Lékařské vědy. Lékařství
- NLK Obory
- radiologie, nukleární medicína a zobrazovací metody
- onkologie
- NLK Publikační typ
- kolektivní monografie
This paper evaluates and compares the properties of directly compressible tabletting materials and matrix tablets containing a combination of α-lactose monohydrate and microcrystalline cellulose in the 3:1 ratio in a physical mixture and in a coprocessed dry binder. Tested parameters include flow properties, compressibility, compactibility and the rate of drug release from tablets. Compressibility is evaluated by means of the energy profile of the compression process. Compactibility is evaluated by means of the tensile strength of the tablets. Dissolution testing is done using the rotating basket method. Dissolution profiles are evaluated by non-linear regression analysis. Total energy of compression and plasticity values were higher in tabletting materials with the coprocessed dry binder. Increasing additions of polyvinyl alcohol decreased the values of total energy of compression, plasticity, tensile strength of tablets and drug release rate. Dissolution behaviour of tablets, which contained the physical mixture or coprocessed dry binder and the same amount of polyvinyl alcohol, was comparable.
- MeSH
- celulosa chemie MeSH
- farmaceutická chemie metody MeSH
- farmaceutická technologie metody MeSH
- kyselina salicylová aplikace a dávkování chemie MeSH
- laktosa chemie MeSH
- nelineární dynamika MeSH
- pevnost v tahu MeSH
- polyvinylalkohol chemie MeSH
- pomocné látky chemie MeSH
- rozpustnost MeSH
- tablety MeSH
- uvolňování léčiv MeSH
- Publikační typ
- časopisecké články MeSH
- srovnávací studie MeSH
This paper deals with a study of the novel coprocessed dry binder Combilac®, which contains 70% of α-lactose monohydrate, 20% of microcrystalline cellulose and 10% of native corn starch. These tests include flow properties, compressibility, lubricant sensitivity, tensile strength and disintegration time of tablets. Compressibility is evaluated by means of the energy profile of compression process, test of stress relaxation and tablet strength. The above-mentioned parameters are also evaluated in the physical mixture of α-lactose monohydrate, microcrystalline cellulose and native corn starch and compared with Combilac. Combilac shows much better flowability than the physical mixture of the used dry binders. Its compressibility is better, tablets possess a higher tensile strength. Neither Combilac, nor the physical mixture can be compressed without lubricants due to high friction and sticking to the matrix. Combilac has a higher lubricant sensitivity than the physical mixture of the dry binders. Disintegration time of Combilac tablets is comparable with the disintegration time of tablets made from the physical mixture.
The paper evaluates and compares the compressibility and compactibility of directly compressible tableting materials for the preparation of hydrophilic gel matrix tablets containing tramadol hydrochloride and the coprocessed dry binders Prosolv® SMCC 90 and Disintequik™ MCC 25. The selected types of hypromellose are Methocel™ Premium K4M and Methocel™ Premium K100M in 30 and 50 % concentrations, the lubricant being magnesium stearate in a 1 % concentration. Compressibility is evaluated by means of the energy profile of compression process and compactibility by the tensile strength of tablets. The values of total energy of compression and plasticity were higher in the tableting materials containing Prosolv® SMCC 90 than in those containing Disintequik™ MCC 25. Tramadol slightly decreased the values of total energy of compression and plasticity. Tableting materials containing Prosolv® SMCC 90 yielded stronger tablets. Tramadol decreased the strength of tablets from both coprocessed dry binders.
- MeSH
- celulosa chemie MeSH
- deriváty hypromelózy chemie MeSH
- gely MeSH
- hydrofobní a hydrofilní interakce MeSH
- kyseliny stearové chemie MeSH
- mechanické jevy MeSH
- opioidní analgetika chemie MeSH
- pevnost v tahu MeSH
- pevnost v tlaku MeSH
- pomocné látky chemie MeSH
- přenos energie MeSH
- příprava léků * MeSH
- pružnost MeSH
- tablety MeSH
- tramadol chemie MeSH
- viskozita MeSH
- Publikační typ
- časopisecké články MeSH
- srovnávací studie MeSH
- Geografické názvy
- Česká republika MeSH
The aim of this study is to present the possibility of using of co-processed dry binders for formulation of matrix tablets with drug controlled release. Hydrophilic matrix tablets with tramadol hydrochloride, hypromellose and different co-processed dry binders were prepared by direct compression method. Hypromelloses Methocel™ K4M Premium CR or Methocel™ K100M Premium CR were used as controlled release agents and Prosolv® SMCC 90 or Disintequik™ MCC 25 were used as co-processed dry binders. Homogeneity of the tablets was evaluated using scanning electron microscopy and energy dispersive X-ray microanalysis. The release of tramadol hydrochloride from prepared formulations was studied by dissolution test method. The dissolution profiles obtained were evaluated by non-linear regression analysis, release rate constants and other kinetic parameters were determined. It was found that matrix tablets based on Prosolv® SMCC 90 and Methocel™ Premium CR cannot control the tramadol release effectively for >12h and tablets containing Disintequik™ MCC 25 and Methocel™ Premium CR >8h.
The article evaluates the compressibility and release rate of the active ingredient from hydrophilic-matrix tablets containing Carbopol®71G NF or Carbopol®971P NF polymer in concentrations of 5, 10, 15 and 20 mass %. The compressibility was evaluated by means of the energy profile of compression and tensile strengths of tablets. The total energy of compression decreased with increasing concentrations of both Carbopols, more markedly in the case of powdered Carbopol. Plasticity decreased with the compression force being slightly higher in tableting materials containing granulated Carbopol. Tensile strength of tablets increased with increasing concentration of powdered Carbopol, in the case of a granulated Carbopol the dependence was reversed. The release rate of the active ingredient decreased with increasing concentrations of Carbopols. The powdered Carbopol prolonged the release more than the granulated ones, even at the lowest concentration used.
The paper compared two spray-dried lactoses Flowlac 100 and SuperTab 14SD from the standpoint of tensile strength and disintegration time of tablets, the effect of an addition of the lubricant magnesium stearate and silicified microcrystalline cellulose on these properties, and also from the standpoint of the energy profile of compression. The comparison of the values was performed at the compression force of 15 kN. The strength of tablets was higher in the case of SuperTab 14SD, an increase in the concentration of magnesium stearate did not decrease tablet strength. Prosolv SMCC 90 increased the strength of tablets and made it equal for both lactoses, but it also increased the sensitivity to the added lubricant. The disintegration time of tablets was shorter in the case of SuperTab 14SD, an increased concentration of magnesium stearate prolonged it, and an addition of Prosolv SMCC 90 shortened it and made it equal for both lactoses. From the energy standpoint, the maximal energy was higher in the case of SuperTab 14SD, an addition of Prosolv SMCC 90 increased it and again made it equal for both lactoses. The differences in the values of the maximal energy were primarily due to the values of the energy for friction and the energy accumulated by the tablet after compression, and there was no marked difference in the values of the energy of decompression. SuperTab 14SD showed a higher plasticity than Flowlac 100.
- MeSH
- aerosoly MeSH
- celulosa chemie MeSH
- farmaceutická chemie MeSH
- farmaceutická technologie metody MeSH
- kinetika MeSH
- kyseliny stearové chemie MeSH
- laktosa chemie MeSH
- lubrikanty chemie MeSH
- pevnost v tahu MeSH
- pevnost v tlaku MeSH
- pomocné látky chemie MeSH
- rozpustnost MeSH
- tablety MeSH
- vysoušení MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
- srovnávací studie MeSH
The paper evaluates and compares the strength and disintegration time of tablets and the energy profile of compression in dependence on compression force in the coprocessed dry binders LubriToseTM SD and LubriToseTM AN. These substances are further compared in these parameters with the physical mixtures of the pertinent lactoses with various lubricants in a concentration of 4 %. The lubricants employed included glycerol monostearate, magnesium stearate, Poloxamer 407, and sodium stearyl fumarate.
Tensile strength and disintegration time of tablets from aglomerated α-lactose monohydrate or anhydrous β- lactose as well as the energy profile of compression (at 11 kN) were evaluated in dependence on the lubricant (Mg stearate) concentration and an addition of microcrystalline cellulose (25 %). No statistically significant differences were found between the corresponding values of tensile strength for tablets from both lactoses. Microcrystalline cellulose increased the strength, shortened the disintegration times and markedly decreased the differences in compression energies and plasticity of both types of tablets. Mg stearate prolonged the disintegration times and markedly decreased the tablet strength only in the presence of microcrystalline cellulose. The disintegration times were markedly longer for the tablets from anhydrous β-lactose. The total energy of compression and plasticity were higher for aglomerated α-lactose monohydrate tablets.
V práci je porovnávána lisovatelnost dvou přímo lisovatelných isomaltů galenIQ™ 720 a galenIQ™ 721 prostřednictvím energetického hodnocení lisovacího procesu pomocí záznamu „síla-dráha“. Jsou zde hodnoceny energie na tření, energie akumulovaná tabletou, energie dekomprese, energie lisování a plasticita, a to u čistých suchých pojiv, u suchých pojiv s mazadly (0,5 a 1% stearanu hořečnatého a stearylfumarátu sodného) a dále u tabletovin s modelovými léčivy kyselinou acetylsalicylovou a askorbovou. Z výsledků práce vyplynulo, že nižší hodnoty energie na tření i na lisování při stejné lisovací síle vykazuje látka galenIQ 720, proto je lépe lisovatelná než látka galenIQ 721.
The paper compares the compressibility of two directly compressible isomalts, galenIQ™ 720 and galenIQ™ 721, using the energy evaluation of the compaction process by means of the force-?-displacement profiles. It evaluates the energies for friction, energies accumulated by the tablet, energy of decompression, energy of compaction and plasticity in pure dry binders, in dry binders with lubricants (0.5 and 1% of magnesium stearate and sodium stearyl fumarate) and further in the tableting materials containing the model ingredients acetylsalicylic acid and ascorbic acid. The results of the study have revealed that lower values of the energy for friction and compaction with the identical compression force are found by the substance galenIQ 720, which is therefore better compressible than the substance galenIQ 721.
