170 research outputs found
Controlled release floating multiparticulates of metoprolol succinate by hot melt extrusion
YesWe present hot melt extrusion (HME) for the design of floating multiparticulates. Metoprolol succinate was selected as the model drug. Our foremost objective was to optimize the components Eudragit® RS PO, polyethylene oxide (PEO) and hydroxypropyl methylcellulose (HPMC) to balance both buoyancy and controlled release. Gas generated by sodium bicarbonate in acidic medium was trapped in the polymer matrix to enable floating. Eudragit® RS PO and PEO with sodium bicarbonate resulted in multiparticulates which exhibited rapid flotation within 3 minutes but inadequate total floating time (TFT) of 3 hours. Addition of HPMC to the matrix did not affect floating lag time (FLT), moreover TFT increased to more than 12 hours with controlled release of metoprolol succinate. Floating multiparticulates exhibited t50% of 5.24 hours and t90% of 10.12 hours. XRD and DSC analysis revealed crystalline state of drug while FTIR suggested nonexistence of chemical interaction between the drug and the other excipients. The assay, FLT, TFT and the drug release of the multiparticulates were unchanged when stored at 40 °C/75%RH for 3 months confirming stability. We present floating multiparticulates by HME which could be extrapolated to a range of other drugs. Our approach hence presents platform technology for floating multiparticulates
Ispitivanje vosku sličnih svojstava ibuprofena kao veziva
The study investigates ibuprofen with wax-like properties as a multifunctional agent (as an active component and as a melt binder). Binding efficiency was compared with granules prepared by wet granulation using polyvinylpyrollidone (PVP K-30) as a binder for micromeritic, physical and mechanical properties such as angle of repose, particle size distribution Carr’s index, Hausner’s ratio, crushing strength, percentage fines, Heckel plot study and tensile strength. To check the binder distribution during melt granulation, content uniformity was determined. To check changes in the physical state of ibuprofen, XRPD, DSC and FTIR studies were carried out. The present study underlines the fact that ibuprofen may be adopted as a binder in ibuprofen formulations using the melt granulation techniqueSvrha rada je ispitivanje vosku sličnih svojstava ibuprofena, tvari s višeznačnom funkcijom (ljekovita tvar i vezivo pri granulaciji). Vezivna svojstva uspoređivana su s granulama pripravljenim vlažnom granulacijom s polivinilpirolidonom (PVP K-30) kao vezivom, ispitivanjem mikrometričkih, fizikalnih i mehaničkih svojstava kao što su sipkost materijala, Carrov indeks distribucije veličine čestica, Hausnerov parameter, otpornost na vlak. Da bi se ispitala distribucija veziva tijekom granulacije taljenjem određivana je ujednačenost sadržaja. Za praćenje promjena fizikalnih svojstava ibuprofena snimljeni su XRPD, DSC, FTIR spektri. Istraživanja ukazuju da se ibuprofen može koristiti kao vezivo u ljekovitim pripravcima ibuprofena u kojima se primjenjuje granulacija taljenjem
Coformer Replacement as an Indicator for Thermodynamic Instability of Cocrystals: Competitive Transformation of Caffeine:Dicarboxylic Acid
yesThe thermodynamic stability of caffeine (CA) cocrystals with dicarboxylic acids (DAs) as coformers was investigated in the presence of a range of structurally related dicarboxylic acids (SRDs). Two experimental conditions (slurry and dry-grinding) were studied for mixing the cocrystal and the SRD additive. The additives oxalic, malonic and glutaric acid led to the replacement of the acid coformer for certain cocrystals. Interestingly, a change in stoichiometry was observed for the CA:maleic acid system. A stability order among the cocrystals was established depending on their tendency to replace the coformer. To understand the factors controlling the relative stabilities, lattice energies were calculated using dispersion corrected Density Functional Theory (DFT). Gibbs free energy changes were calculated from experimental solubilities. The observed stability order corroborated well with lattice energy and Gibbs free energy computations
Investigation of Plasma Treatment on Micro-Injection Moulded Microneedle for Drug Delivery
YesPlasma technology has been widely used to increase the surface energy of the polymer surfaces for many industrial applications; in particular to increase in wettability. The present work was carried out to investigate how surface modification using plasma treatment modifies the surface energy of micro-injection moulded microneedles and its influence on drug delivery. Microneedles of polyether ether ketone and polycarbonate and have been manufactured using micro-injection moulding and samples from each production batch have been subsequently subjected to a range of plasma treatment. These samples were coated with bovine serum albumin to study the protein adsorption on these treated polymer surfaces. Sample surfaces structures, before and after treatment, were studied using atomic force microscope and surface energies have been obtained using contact angle measurement and calculated using the Owens-Wendt theory. Adsorption performance of bovine serum albumin and release kinetics for each sample set was assessed using a Franz diffusion cell. Results indicate that plasma treatment significantly increases the surface energy and roughness of the microneedles resulting in better adsorption and release of BSA
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Polymorphs of Curcumin and Its Cocrystals With Cinnamic Acid
YesWe report formation of polymorphs and new eutectics and cocrystals of curcumin, a sparingly water-soluble active component in turmeric, structurally similar to cinnamic acid. The curcumin polymorphs were formed using liquid antisolvent precipitation, where acetone acted as a solvent and water was used as the antisolvent. The metastable form 2 of curcumin was successfully prepared in varied morphology over a wide range of solvent-to-antisolvent ratio and under acidic pH conditions. We also report formation of new eutectics and cocrystals of curcumin with cinnamic acid acting as a coformer. The binary phase diagrams were studied using differential scanning calorimetry and predicted formation of the eutectics at the curcumin mole fraction of 0.15 and 0.33, whereas a cocrystal was formed at 0.3 mole fraction of curcumin in the curcumin–cinnamic acid mixture. The formation of the cocrystal was supported with X-ray powder diffraction, the enthalpy of fusion values, Fourier-transform infrared spectroscopy, and scanning electron microscopy. The hydrogen bond interaction between curcumin and cinnamic acid was predicted from Fourier-transform infrared spectra, individually optimized curcumin and cinnamic acid structures by quantum mechanical calculations using Gaussian-09 and their respective unit cell packing structures
Mechanism of Hydrogen-Bonded Complex Formation between Ibuprofen and Nanocrystalline Hydroxyapatite.
Nanocrystalline hydroxyapatite (nanoHA) is the main hard component of bone and has the potential to be used to promote osseointegration of implants and to treat bone defects. Here, using active pharmaceutical ingredients (APIs) such as ibuprofen, we report on the prospects of combining nanoHA with biologically active compounds to improve the clinical performance of these treatments. In this study, we designed and investigated the possibility of API attachment to the surface of nanoHA crystals via the formation of a hydrogen-bonded complex. The mechanistic studies of an ibuprofen/nanoHA complex formation have been performed using a holistic approach encompassing spectroscopic (Fourier transform infrared (FTIR) and Raman) and X-ray diffraction techniques, as well as quantum chemistry calculations, while comparing the behavior of the ibuprofen/nanoHA complex with that of a physical mixture of the two components. Whereas ibuprofen exists in dimeric form both in solid and liquid state, our study showed that the formation of the ibuprofen/nanoHA complex most likely occurs via the dissociation of the ibuprofen dimer into monomeric species promoted by ethanol, with subsequent attachment of a monomer to the HA surface. An adsorption mode for this process is proposed; this includes hydrogen bonding of the hydroxyl group of ibuprofen to the hydroxyl group of the apatite, together with the interaction of the ibuprofen carbonyl group to an HA Ca center. Overall, this mechanistic study provides new insights into the molecular interactions between APIs and the surfaces of bioactive inorganic solids and sheds light on the relationship between the noncovalent bonding and drug release properties
Priprava i evaluacija plutajućih matriksa rizedronat natrija Gelucire® 39/01
Incorporation of bisphosphonates in the lipid reduces gastric irritation. Only gastric retention with sustained release allows the drug to reach the duodenum and jejunum and improves the availability of bisphosphonates. Risedronate sodium and Gelucire® 39/01 floating matrices were prepared using melt solidification. The sustained release floating matrices were evaluated for in vitro and in vivo floating ability and in vitro drug release. Ageing of the matrices was studied by differential scanning calorimetry, hot stage polarizing microscopy, scanning electron microscopy and in vitro drug release. Ageing causes changes in the crystal structure of the Gelucire®, which is responsible for increase in drug release.Uklapanje bisfosfonata u lipide smanjuje iritaciju želuca. Samo zadržavanje u želucu s usporenim oslobađanjem omogućava da ljekovita tvar dospije u duodenum i jejunum i povećava bioraspoloživost bisfosfonata. Rizedronat natrij i Gelucire® 39/01 plutajući matriksi pripravljeni su metodom taljenja i očvršćivanja. Proučavana je sposobnost plutanja pripremljenih matriksa in vitro i in vivo te oslobađanje ljekovite tvari. Starenje matriksa proučavano je diferencijalnom pretražnom kalorimetrijom, polarizirajućom mikroskopijom s vrućom pločom i pretražnom elektronskom mikroskopijom. Starenje uzrokuje promjene u kristalnoj strukturi Gelucire® zbog kojih se povećava oslobađanje ljekovite tvari
Samoemulzirajući pripravci za peroralnu primjenu simvastatina: Ispitivanja in vitro i in vivo
The objective of the present work was to formulate a self-emulsifying drug delivery system (SEDDS) for simvastatin, which is widely used in the treatment of hypercholesterolemia and dyslipidemia as an adjunct to diet. Simvastatin SEDDS were formulated using a 1:1 (V/V) mixture of diesters of caprylic/capric acids and polyglycolyzed glycerides with varying concentrations of polyoxy 35 castor oil and C8/C10 mono-/diglycerides. The developed SEDDS were evaluated for turbidimetry, droplet size analysis, drug content and in vitro diffusion profiles. In vivo performance of the optimized formulation was evaluated in rats using pharmacodynamic marker parameters like plasma total cholesterol (CH), triglycerides (TG) and high-density lipoprotein (HDL-CH) for 21 days. SEDDS containing 9.1% (m/m) simvastatin and 23%, (m/m) of each excipient showed minimum mean droplet size (124 nm) and optimal drug diffusion. This test formulation showed significant reduction in plasma CH and TG (around 5-fold and 4-fold, respectively), while HDL-CH concentration was markedly higher (2-fold) compared a reference simvastatin suspension formulation after oral administration for 21 days of study. Test formulation has shown enhanced pharmacodynamic performance compared to reference formulation in rats. The study illustrated the potential of simvastatin SEDDS for oral administration and its biopharmaceutic performance.Cilj rada bio je pripraviti samoemulzirajući sustav za isporuku lijeka (SEDDS) za simvastatin, hipolipemik koji se uz dijetu upotrebljava u terapiji hiperkolesterolemije i dislipidemije. Simvastatin SEDDS su pripravljene koristeći smjesu 1:1 (V/V) diestera kaprilne i kaprinske kiseline i poliglikoliziranih glicerida s različitim koncentracijama polioksil 35 kastorovog ulja i C8/C10 mono-/diglicerida. Pripravcima su ispitana turbidimetrijska svojstva, veličina čestica, udio lijeka i in vitro difuzijski profil. U pokusima in vivo na štakorima praćeni su parametri farmakodinamičkih markera kao što su ukupni kolesterol u plazmi (CH), trigliceridi (TG) i lipoproteini velike gustoće (HDL-CH) tijekom 21 dana. Pripravci koji sadrže 9,1% (m/m) simvastatina i 23% (m/m) svake od pomoćnih tvari imaju najmanju prosječnu veličinu čestica (124 nm) i iz njih je difuzija lijeka optimalna. Ispitivani pripravci značajno snizuju CH i TG u plazmi (5, odnosno 4 puta), dok je koncentracija HDL-CH ostaje izrazito visoka, 2 puta viša u usporedbi s referentnom suspenzijom simvastatina poslije peroralne primjene tijekom 21 dan. Ispitivani pripravci imaju bolji farmakodinamički profil u odnosu na referentni pripravak pa imaju veliki potencijal za peroralnu primjenu simvastatina
Ispitivanje vosku sličnih svojstava ibuprofena kao veziva
The study investigates ibuprofen with wax-like properties as a multifunctional agent (as an active component and as a melt binder). Binding efficiency was compared with granules prepared by wet granulation using polyvinylpyrollidone (PVP K-30) as a binder for micromeritic, physical and mechanical properties such as angle of repose, particle size distribution Carr’s index, Hausner’s ratio, crushing strength, percentage fines, Heckel plot study and tensile strength. To check the binder distribution during melt granulation, content uniformity was determined. To check changes in the physical state of ibuprofen, XRPD, DSC and FTIR studies were carried out. The present study underlines the fact that ibuprofen may be adopted as a binder in ibuprofen formulations using the melt granulation techniqueSvrha rada je ispitivanje vosku sličnih svojstava ibuprofena, tvari s višeznačnom funkcijom (ljekovita tvar i vezivo pri granulaciji). Vezivna svojstva uspoređivana su s granulama pripravljenim vlažnom granulacijom s polivinilpirolidonom (PVP K-30) kao vezivom, ispitivanjem mikrometričkih, fizikalnih i mehaničkih svojstava kao što su sipkost materijala, Carrov indeks distribucije veličine čestica, Hausnerov parameter, otpornost na vlak. Da bi se ispitala distribucija veziva tijekom granulacije taljenjem određivana je ujednačenost sadržaja. Za praćenje promjena fizikalnih svojstava ibuprofena snimljeni su XRPD, DSC, FTIR spektri. Istraživanja ukazuju da se ibuprofen može koristiti kao vezivo u ljekovitim pripravcima ibuprofena u kojima se primjenjuje granulacija taljenjem
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