Starch Source and Its Impact on Pharmaceutical Applications

Starch can be obtained from a variety of plant sources. The specific source of starch, the environmental conditions during starch maturation, and the age of the plant affect the physicochemical composition of the starch. This is because of the effect they have on critical factors especially the amylose amylopectin content of the starch as well as their relative quantities. These factors also affect the starch granule size and size distribution and the levels of minor components such as phosphates, lipids, and the nature of these interactions with amylose and amylopectin. In its wide use as a pharmaceutical excipient especially as binder and disintegrant, unmodified starch is affected in its functionality by the physicochemical properties of the starch. These factors especially by their influence on the swelling power and gelatinization as well as granule size and shape determine the properties of dosage forms in which the starches are used. This results in dosage forms that, although meeting compendial standards, differ in specific properties. The source of starches therefore affects the properties of pharmaceutical dosage forms. This should be taken into consideration in the choice of excipients in drug formulation and before the substitution of one starch for another in a formulation

Učinak molekulske mase karboksimetilceluloze i nekih polimera na usporeno oslobađanje teofilina iz hidrofilnih matriksa

The objective of this study was to investigate the influence of the molecular size of carboxymethylcellulose (cmc) and some hydrophobic polymer additives on the release properties of theophylline from the tablet matrices. The cmc matrices were prepared by the conventional wet granulation method. The granules were evaluated for angles of repose, bulk density, compressibility index, and porosity, while the tablets were subjected to hardness, friability and compression characteristics. All the tablet formulations showed acceptable pharmacotechnical properties. Low molecular size cmc (cmc-L) had the fastest drug release t50% values of 27 min, for medium size cmc (cmc-M) 55 min and high molecular size cmc (cmc-H) 200 min. Overall, results showed that drug release rate decreases with increase in molecular size of cmc. All the polymer additives ethylcellulose (ETC), cellulose acetate phthalate (CAP) and Eudragit l-100 (EUD) retarded theophylline release from cmc-L and cmc-H, with ethylcellulose having the most pronounced effect on cmc-L. Kinetic studies using Hixson-Crowell and Peppas-Ritger equations showed that different drug release mechanisms were involved in controlling drug dissolution from the tablets. Drug release mechanism was influenced by both the molecular size of cmc and the presence of polymer additives.U radu je ispitivan učinak molekulske mase karboksimetilceluloze (cmc) i nekih hidrofobnih polimera kao aditiva na profil oslobađanja teofilina iz tabletnih matriksa. Matriksi s cmc pripremljeni su uobičajenom metodom vlažne granulacije. Granulama je određivana sipkost, gustoća, poroznost i indeks kompresivnosti, dok je tabletama ispitivana tvrdoća, rastrošljivost i kompresibilnost. Sve priređene tablete imala su prihvatljiva farmakotehnološka svojstva. Najbrže vrijeme oslobađanja t50% od 27 min postignuto je iz pripravka cmc male molekulske mase (cmc-L), 55 min iz pripravka cmc srednje molekulske mase (cmc-M) 55 min i 200 min iz pripravka cmc velike molekulske mase (cmc-H). Rezultati ukazuju da se brzina oslobađanja smanjuje povećanjem molekulske mase cmc. Svi polimerni aditivi, etilceluloza, celuloza acetat ftalat i Eudragit l-100 usporili su oslobađanje teofilina iz cmc-L i cmc-H pripravka, a najveći učinak imala je etilceluloza na cmc-L. Kinetičke studije provedene pomoću Hixson-Crowell-ove i Peppas-Ritger-ove jednadžbe ukazuju da su u oslobađanju teofilina iz tableta uključeni različiti mehanizmi. Na mehanizam oslobađanja utjecali su i molekulska masa cmc i prisutnost polimernih aditiva

Polimerne mješavine obložene Eudragitom: Potencijalni sustav za kontroliranu peroralnu isporuku teofilina

Sustained release (SR) dosage forms enable prolonged and continuous deposition of the drug in the gastrointestinal (GI) tract and improve the bioavailability of medications characterized by a narrow absorption window. In this study, a new strategy is proposed for the development of SR dosage forms for theophylline (TPH). Design of the delivery system was based on a sustained release formulation, with a modified coating technique and swelling features aimed to extend the release time of the drug. Different polymers, such as Carbopol 71G (CP), sodium carboxymethylcellulose (SCMC), ethylcellulose (EC) and their combinations were tried. Prepared matrix tablets were coated with a 5 % (m/m) dispersion of Eudragit (EUD) in order to get the desired sustained release profile over a period of 24 h. Various formulations were evaluated for drug concentration and in vitro drug release. It was found that the in vitro drug release rate decreased with increasing the amount of polymer. Coating with EUD resulted in a significant lag phase in the first two hours of dissolution in the acidic pH of simulated gastric fluid (SGF) due to decreased water uptake, and hence decreased driving force for drug release. Release became faster in the alkaline pH of simulated intestinal fluid (SIF) owing to increased solubility of both the coating and matrixing agents. The optimized formulation was subjected to in vivo studies in rabbits and the pharmacokinetic parameters of developed formulations were compared with the commercial (Asmanyl®) formulation. Asmanyl® tablets showed faster absorption (tmax 4.0 h) compared to the TPH formulation, showing a tmax value of 8.0 h. The cmax and AUC values of TPH formulation were significantly (p < 0.05) higher than those for Asmanyl®, revealing relative bioavailability of about 136.93 %. Our study demonstrated the potential usefulness of eudraginated polymers for the oral delivery of the sparingly soluble drug theophylline.Pripravci za produljeno oslobađanje (SR) omogućavaju produljeno i kontinuirano oslobađanje lijeka u gastrointestinalnom (GI) traktu i poboljšavaju bioraspoloživost lijekova s uskim apsorpcijskim prozorom. U radu se predlaže nova strategija za razvoj formulacija s produljenim oslobađanjem teofilina (TPH), koja se temelji na sustavu za produljeno oslobađanje, kojem je u svrhu produljenja vremena oslobađanja modificiran način oblaganja i bubrenja. Korišteni su različiti polimeri, kao što su Carbopol 71G (CP), natrijeva karboksimetilceluloza (SCMC), etilceluloza (EC) i njihove kombinacije. Pripravljene matriks tablete obložene su 5-postotnom (m/m) disperzijom Eudragita (EUD) kako bi se postiglo produljeno oslobađanje tijekom 24 h. U pripravljenim formulacijama određena je koncentracija lijeka i in vitro oslobađanje. Rezultati pokazuju da se povećanjem udjela polimera smanjuje brzina oslobađanja in vitro. Oblaganje s EUD značajno je produljilo lag fazu tijekom prva 2 sata otapanja u kiselom pH simuliranog želučanog soka (SGF). Naime, oblaganje usporava ulazak vode i tako smanjuje pogonsku silu za oslobađanje lijeka. Zbog povećane topljivosti obložnog sloja i matriksa u lužnatom mediju, oslobađanje u simuliranoj intestinalnoj tekućini (SIF) je brže. Optimizirana formulacija ispitana je in vivo na zečevima. Farmakokinetički parametri novih formulacija uspoređivani su s komercijalnim pripravkom Asmanyl®. Asmanyl® tablete pokazuju bržu apsorpciju (tmax 4,0 h) u odnosu na TPH formulaciju (tmax 8,0 h). cmax i AUC vrijednosti TPH formulacije bile su značajno (p < 0,05) više od onih za Asmanyl®, što ukazuje na relativnu bioraspoloživost od oko 136,93 %. Stoga smatramo da su polimeri obloženi eudragitom potencijalno korisni za oralnu upotrebu teško topljivog lijeka teofilina

Micromeritic and compation characterization of Lacapregs: a group of novel multifunctional excipients

In the study, Lacagpregs, a multifunctional excipient series containing lactose, cashew gum and partially pregelatinized starch, were subjected to micromeritic and compaction characterization to identify the most suitable product for tablet formulation. Sieve analysis, fluid displacement, tapping experiment, Heckel analysis and lubricant sensitivity tests were carried out using standard protocols. Excipients’ particle diameters ranged from 232 μm – 320 μm with corresponding median particle diameters of 210 μm and 330 μm. The span ranged from 1.43 – 2.45, an indication of wide particle size distributions. Particle densities of excipients ranged from 1.497 g/ml to 1.503 g/ml without any significant difference. Excipients’ angle of repose ranged from 31.53o – 36.03o, Carr’s index ranged from 17.50% – 24.14%, Hausner’s ratio ranged from 1.21 – 1.32, all indicative of intermediate flow characteristics. Among the excipients, products from longer processing times displayed higher plastic deformation at constant binder concentration. The differences between the yield pressures of the excipients were significant (p &lt; 0.05). The plastic excipients were more lubricant sensitive than the brittle ones. In conclusion, excipients containing cashew gum at 5% and processed with intermediate agitation for a duration of 30-60 min may be the best choice for drug powders with poor compactibility characteristics.Keywords: Lacagpregs, Multifunctional excipient, Micromeritics, CompactibilityJournal of Pharmaceutical and Allied Sciences, Vol. 10 No. 3 (2013

Pharmaceutical Characterization of Aqueous Stem Bark Extract of Bridelia ferruginea Benth (Euphorbiaceae)

Purpose: To characterize some preformulation properties of aqueous stem bark extract of Bridelia ferruginea Benth (Euphorbiaceae) (BF). Methods: The stem bark was extracted by maceration in hot distilled water. Two batches of granules containing the extract were prepared by wet granulation using maize starch, polyvinylpyrrolidone (PVP), Avicel® PH-101, magnesium stearate, acacia and lactose as excipients. Some physicochemical and micromeritic properties of the powdered extract and granules were determined following standard procedures. Results: The pH of the aqueous BF extract was 5.4 ± 0.1 while the moisture content of the dry extract was 12.0 %. Total ash value of the extract was 7.91 ± 0.03. Particle size increased after granulation from 228 to 531 μm in the order: granules 1 > granules 2 > powder. The bulk and tapped densities decreased significantly (p < 0.05) from 0.40 ± 0.04 to 0.77 ± 0.09 and 0.49 ± 0.05 to 0.85 ± 0.09 g/ml, respectively in the order: granules 2 < granules 1 < powder. Similarly, the angle of repose increased after granulation from 24.0 ± 0.5 to 25.4 ± 0.9 o in the order: granules 2 < granules 1 < powder (p < 0.05). The flow rate and compressibility of the granules (2.45 ± 0.08 g/min and 0.17, respectively) improved significantly (p < 0.05) over those of the powdered BF extract (2.34 ± 0.05 g/min and 0.26, respectively). Conclusion: The results of this preformulation study indicates that the powdered extract of Bridelia ferruginea possesses properties that make it suitable for its formulation into standard solid dosage forms

Piloting a smartphone-based application for tracking and supply chain management of medicines in Africa.

A confounding factor for healthcare programmes in African countries is the inability of essential health tools to reach targeted locations and populations, due to poor Logistics Management Information System (LMIS). In a bid to contribute towards addressing these challenges, a pilot study was undertaken to evaluate the tracking ability, reliability and applicability of EASE App, a novel Smart Phone based Application. The App is designed to provide real-time tracking and tracing of commodities as well as curation of data in a cloud based database with restricted access which can be linked with other databases. In this study, NIPRIMAL was labelled with QR codes, and tracked within the Federal Capital Territory, Abuja, Nigeria, using the smartphone based EASE App. Data collected showed that the "EASE App" tracking had accuracy of 100% for date and time of scan, operators' codes and product identity; and 92.83±1.69% and 99.83±0.27% accuracy for GPS mapping label for the city and country, respectively. The GPS mapping label for specific streets, roads or districts, gave an accuracy of about 64.28±3.14%. The technology was able to provide real-time data on user unique identity, user location as well as date/time of use, and the feedback report indicated that it was readily deployable and easy to use. The results demonstrate that the "EASE App" is a promising technology that can support supply chain and related data management challenges in resource poor settings. The potential benefit of the EASE App in strengthening LMIS and distribution chain system in Africa as well as future optimization of the App are discussed