compactability Dotaz Zobrazit nápovědu
The objective of the present research is to evaluate directly compressible chitosan-based tableting materials for the formulation of mucoadhesive matrix tablets intended for targeted drug release to distal segments of the GIT. The influence of sodium alginate, hypromellose, and silicified microcrystalline cellulose (P90) on compressibility, compactability and lubricant sensitivity ratio was tested. Furthermore, the rheological properties of the hydrated surface layer of the matrix tablets and the mucoadhesion to a mucin substrate were analysed. Compressibility was evaluated using the energy profile of the compression process, compactability by means of the tensile strength of tablets, and lubricant sensitivity ratio was calculated to assess the sensitivity to lubricant. Addition of P90 to chitosan improved compressibility, which is demonstrated by the increase in the energy of plastic deformation and the higher tensile strength of tablets. P90 also significantly reduced the high lubricant sensitivity of chitosan. Presence of retarding components led to a decrease in Emax. All tested matrix tablets revealed a good mucoadhesion without a negative effect of P90 content. The viscosity of a gel layer on the surface of matrix tablets containing hypromellose was higher compared to those with sodium alginate. This was not reflected in the adhesive strength of the tablets. The formulated tableting materials combining chitosan and P90 are a suitable matrix for incorporation of an active ingredient, whose delayed release in the intestine can be achieved by the functionality of the chitosan-sodium alginate complex.
- Klíčová slova
- chitosan, compactability, compressibility, matrix tablets, mucoadhesion, silicified microcrystalline cellulose,
- Publikační typ
- časopisecké články MeSH
Co-processed dry binders for ODTs are important multifunctional excipients for tablet manufacturing by direct compression. Testing their binary mixtures with lubricants is an important aspect of their use in combination with drugs. The aim of this study was to evaluate the rheological and compression properties of lubricated mixtures of co-processed dry binders Parteck® ODT, Prosolv® ODT G2 and Ludiflash®, and subsequently also the compactability and disintegration time of the tablets made thereof. The lubricants employed were magnesium stearate and sodium stearyl fumarate in the concentrations of 0.5% and 1%. The best flowability was shown by Prosolv® ODT G2 combined with magnesium stearate in the concentration of 0.5%. Lubricated mixtures with Prosolv® ODT G2 showed a lower angle of internal friction as well as lower pre-compression energy values. The values of plastic deformation energy were the highest in the case of Prosolv® ODT G2, which was also reflected in the highest tablet strength. On the contrary, the ejection force values were the lowest for this co-processed dry binder. Magnesium stearate reduced the ejection force more effectively than sodium stearyl fumarate. Prosolv® ODT G2 tablets exhibited the highest tensile strength and shortest disintegration time.
- Klíčová slova
- Co-processed dry binders, Compactability, Disintegration time, Energy profile of compression, Flow properties, Orally disintegrating tablets,
- MeSH
- lubrikanty * MeSH
- pevnost v tahu MeSH
- pomocné látky * MeSH
- tablety MeSH
- Publikační typ
- časopisecké články MeSH
- Názvy látek
- lubrikanty * MeSH
- pomocné látky * MeSH
- tablety MeSH
An important feature of orodispersible tablets (ODTs) is the convenient administration of the drugs, in some cases, faster onset of action, stability maintenance, and dose precision. This work focused on the preparation of ODTs containing mannitol-based co-processed excipients Prosolv® ODT G2, Ludiflash® and Parteck® ODT in combination with tramadol, captopril, and domperidone by direct compression. Prosolv® ODT G2 showed high energy of plastic deformation due to the content of microcrystalline cellulose. Parteck® ODT provided compact tablets due to the content of granulated mannitol. All drugs decreased tensile strength, increased friability, prolonged disintegration time, and decreased the porosity of tablets. Tablets containing Prosolv® ODT G2 with captopril, domperidone, and tramadol; and Parteck® ODT with domperidone met the requirements for ODTs production, i.e., friability ≤ 1% and disintegration time ≤ 180 s, fast wetting time, high water absorption ratio, and adequate tensile strength. The disintegration time was tested using both the pharmacopeial method and the BJKSN-13 apparatus. The results indicate the significant difference between these methods, with the disintegration time being longer when tested with the BJKSN-13 instrument.
- Klíčová slova
- Co-processed excipients, Compactability, Disintegration time, Energy profile of compression, Orodispersible tablets, Tomography,
- MeSH
- aplikace orální MeSH
- domperidon MeSH
- kaptopril MeSH
- mannitol chemie MeSH
- pomocné látky * chemie MeSH
- příprava léků metody MeSH
- rozpustnost MeSH
- tablety chemie MeSH
- tramadol * MeSH
- Publikační typ
- časopisecké články MeSH
- Názvy látek
- domperidon MeSH
- kaptopril MeSH
- mannitol MeSH
- pomocné látky * MeSH
- tablety MeSH
- tramadol * MeSH
Taurine, a sulphur - containing amino acid, has been termed a functional nutrient. Its synthetic form is a common ingredient in supplements and energy drinks. There is no information concerning taurine impact on bone microstructure after prolonged supplemental use. Also, differences in bone parameters of mice following taurine exposure are unknown. In this study, a detailed microstructure of compact and trabecular bone tissues of mice subchronically exposed to taurine was determined. Animals (n=12) were segregated into three groups: E1 group - mice received 20 mg/kg b.w. of taurine per day during 8 weeks; E2 group - mice were fed by taurine at a dose of 40 mg/kg b.w. for 8 weeks and a control (C) group. Decreased density of secondary osteons, increased sizes of primary osteon's vascular canals (P<0.05) were observed in taurine - treated animals. Cortical bone thickness, trabecular thickness were decreased (P<0.05) in E1 group, and relative volume of trabecular bone was lower (P<0.05) in E2 group as compared to C group. According to our results, prolonged taurine exposure at the doses used in this study can negatively affect both compact and trabecular bone tissues microstructure.
- MeSH
- femur účinky léků patologie fyziologie MeSH
- kortikální kost cytologie účinky léků fyziologie MeSH
- kostní denzita účinky léků fyziologie MeSH
- myši MeSH
- náhodné rozdělení MeSH
- rozvrh dávkování léků MeSH
- taurin aplikace a dávkování toxicita MeSH
- zvířata MeSH
- Check Tag
- myši MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- Názvy látek
- taurin MeSH
The paper deals with a study of tensile strength and disintegration time of compacts made from silicified microcrystalline celluloses, Prosolv SMCC 90, and Prosolv HD 90, in dependence on compression force, addition of two types of lubricants, and two active ingredients. The lubricants were magnesium stearate and sodium stearyl fumarate in a concentration of 0.5%, the active ingredients being ascorbic acid and acetylsalicylic acid in a concentration of 50%. Prosolv SMCC 90 proved to be better compatible than Prosolv HD 90; the compacts were of higher strength, which was markedly increased with increasing compression force. Prosolv HD 90 was more sensitive to additions of lubricants, and a greater decrease in strength was recorded due to the influence of sodium stearyl fumarate. The effect of lubricants on the strength of compacts in the presence of active ingredients was not identical. The disintegration time of compacts from Prosolv HD 90 without as well as with lubricants was shorter than from Prosolv SMCC 90 and was increasing with increasing compression force. Disintegration time was increased with added lubricants, and it was markedly shortened by addition of active ingredients. Compacts containing ascorbic acid possessed a shorter disintegration time than those containing acetylsalicylic acid, and it was not markedly influenced by the presence of lubricants.
- MeSH
- Aspirin chemie MeSH
- celulosa chemie MeSH
- farmaceutická chemie MeSH
- farmaceutická technologie MeSH
- fumaráty chemie MeSH
- kyselina askorbová chemie MeSH
- kyseliny stearové chemie MeSH
- lubrikace MeSH
- oxid křemičitý chemie MeSH
- pevnost v tahu MeSH
- pomocné látky chemie MeSH
- tablety chemie MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
- srovnávací studie MeSH
- Názvy látek
- Aspirin MeSH
- celulosa MeSH
- fumaráty MeSH
- kyselina askorbová MeSH
- kyseliny stearové MeSH
- microcrystalline cellulose MeSH Prohlížeč
- oxid křemičitý MeSH
- pomocné látky MeSH
- sodium stearyl fumarate MeSH Prohlížeč
- stearic acid MeSH Prohlížeč
- tablety MeSH
The paper compares the compressibility of two directly compressible isomalts, galenIQ 720 and galenIQ721, 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.
Soil compaction represents a major challenge for modern agriculture. Compaction is intuitively thought to reduce root growth by limiting the ability of roots to penetrate harder soils. We report that root growth in compacted soil is instead actively suppressed by the volatile hormone ethylene. We found that mutant Arabidopsis and rice roots that were insensitive to ethylene penetrated compacted soil more effectively than did wild-type roots. Our results indicate that soil compaction lowers gas diffusion through a reduction in air-filled pores, thereby causing ethylene to accumulate in root tissues and trigger hormone responses that restrict growth. We propose that ethylene acts as an early warning signal for roots to avoid compacted soils, which would be relevant to research into the breeding of crops resilient to soil compaction.
- MeSH
- Arabidopsis genetika růst a vývoj metabolismus MeSH
- ethyleny metabolismus MeSH
- kořeny rostlin růst a vývoj metabolismus MeSH
- proteiny huseníčku genetika metabolismus MeSH
- půda * MeSH
- receptory buněčného povrchu genetika metabolismus MeSH
- regulátory růstu rostlin metabolismus MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
- Názvy látek
- EIN2 protein, Arabidopsis MeSH Prohlížeč
- ethylene MeSH Prohlížeč
- ethyleny MeSH
- proteiny huseníčku MeSH
- půda * MeSH
- receptory buněčného povrchu MeSH
- regulátory růstu rostlin MeSH
- MeSH
- kortikální kost chirurgie MeSH
- kyretáž * metody MeSH
- lidé MeSH
- nádory kostí * chirurgie patologie sekundární MeSH
- Check Tag
- lidé MeSH
- Publikační typ
- časopisecké články MeSH
Acrylamide (AA) is one of the most common toxins in foods. Its effect on bone microstructure has not been investigated. The aim of our study was to analyze the impact of acute exposure to AA on femoral bone microstructure in mice. Adult animals were treated perorally with 2 doses of AA (E1 group, 1 mg/kg b.w.) in a 24-h period and with 3 doses of AA (E2 group, 1 mg/kg b.w.) in a 48-h period. Mice exposed to AA had smaller sizes of primary osteon's vascular canals. Secondary osteons were significantly smaller in mice from E2 group; however their increased number (from 38 % to 77 %) was identified in both E1 and E2 groups. In these groups, a higher number of resorption lacunae (from 100 % to 122 %) was also found. The values for bone volume, trabecular number were increased and that for trabecular separation was decreased in mice administered AA. Significantly higher value of bone surface was observed in mice from E1 group whereas trabecular thickness was increased in E2 group. The effect of AA on microstructure of compact and trabecular bone tissues is different. In our study, one dose of AA was used and acute effects of AA were investigated. Therefore, further studies are needed to study mechanisms by which AA acts on bone.
- MeSH
- akrylamid toxicita MeSH
- femur diagnostické zobrazování účinky léků patologie MeSH
- kontaminace potravin * MeSH
- kortikální kost diagnostické zobrazování účinky léků patologie MeSH
- myši MeSH
- rentgenová mikrotomografie MeSH
- trabekulární kostní tkáň diagnostické zobrazování účinky léků patologie MeSH
- zvířata MeSH
- Check Tag
- mužské pohlaví MeSH
- myši MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- Názvy látek
- akrylamid MeSH
The phospholipid content of the spongious and compact musculature of the heart of the carp (Cyprinus carpio) was compared. The content of phospholipids is higher in the spongious musculature, the greatest difference being in the content of diphosphatidylglycerol: 2.53 mumol P . g-1 wet weight in the spongious layer and 1.29 mumol P . g-1 wet weight in the compact one. In both tissues plasmalogens represent 20-27% of the tissue content of choline and ethanolamine phosphoglycerides.
- MeSH
- Cyprinidae metabolismus MeSH
- fosfolipidy metabolismus MeSH
- kapři metabolismus MeSH
- kardiolipiny metabolismus MeSH
- myokard metabolismus MeSH
- srdce anatomie a histologie MeSH
- tkáňová distribuce MeSH
- zvířata MeSH
- Check Tag
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- srovnávací studie MeSH
- Názvy látek
- fosfolipidy MeSH
- kardiolipiny MeSH