Formulation and evaluation of a sublingual tablet containing terbutaline sulphate: optimisation and in vivo studies

La finalidad de este trabajo de investigación es la formulación de un comprimido sublingual de sulfatode terbutalina de acción rápida y mejorar la biodisponibilidad y el cumplimiento de las pautas por partedel paciente. Para la preparación de los gránulos se utilizó una técnica de granulación húmeda. Seprepararon formulaciones basadas en el diseño factorial con variables de formulación 32: la cantidad decelulosa microcristalina (MCC) (X1) y la crospovidona como componente bioadhesivo (X2). Comovariables de respuesta se evaluaron la resistencia al aplastamiento, la friabilidad y el tiempo de desintegración(DT). Los principales efectos y términos de interacción se evaluaron cuantitativamente medianteun modelo cuadrático. Los resultados revelaron que la cantidad de MCC y crospovidona afectabansignificativamente a las variables de respuesta. La formulación optimizada de comprimidos contiene 31,5mg de MCC y 4,5 mg de crospovidona, se desintegra en un período corto con un índice DT de 30,2+ 5,5 seg. y tiene una resistencia al aplastamiento suficiente y una friabilidad aceptable. Las concentracionesplasmáticas de terbutalina se obtuvieron a los 5 minutos. Los resultados indican que lacrospovidona, un componente bioadhesivo, impide tragar la terbutalina, sin afectar a su liberación yabsorción. En conclusión, la formulación del comprimido sublingual se puede extrapolar a otros fármacosen los que se desee una absorción rápida.The objective of this research was to formulate a sublingual tablet formulation of terbutaline for rapidaction, and to improve both bioavailability and patient compliance to therapy. A wet granulation techniquewas adapted to prepare the granules. Granule formulations were prepared using an adapted wet granulationtechnique based on a 32 full factorial design. The formulation variables were expressed as follows;quantity of microcrystalline cellulose (MCC), (X1), and bioadhesive component crospovidone, (X2),while crushing strength, friability and disintegration time (DT) were determined as response variables.The main effects and interaction terms were quantitatively evaluated using a quadratic model. The resultsobtained showed that the quantity of MCC and crospovidone significantly affect response variables. Anoptimised tablet formulation, containing 31.5 mg of MCC and 4.5 mg of crospovidone, provides a shortDT of 30.2 + 5.5 sec with sufficient crushing strength and acceptable friability, while DT for serumconcentrations of terbutaline were obtained within 5 min. The results indicate that the inclusion ofcrospovidone, a bioadhesive component, in sublingual tablet formulations, makes the swallowing of tablets unnecessary, because the release and absorption of the terbutaline in such formulations isacceptably effective. In conclusion, the developed sublingual tablet formulations is of interest, becauseit can be extrapolated to other drugs, where rapid absorption is desirable

Development of gastro retentive drug delivery system of cephalexin by using factorial design

The objective of this research work was to formulate and optimize the floating drug delivery system containing cephalexin using 23 factorial design. Floating tablets were prepared by direct compression method incorporating HPMC K4M, xanthan gum, guar gum, sodium bicarbonate and tartaric acid as gas generating agent. The influence of independent variables like, polymer: polymer ratio, polymer type and tartaric acid on floating lag time and cephalexin release profile were studied. The diffusion exponent (n) of Krosmeyer Peppas for optimized formulation was found to be 0.635 which indicates the mechanism of drug release was anomalous transport. Floating lag time of optimized formulation was 1.50 min and remained buoyant for 24 hrs. Optimized formulation was checked for stability at 40ºC / 75% RH which was found to be stable. Scanning electron microscopy study revealed gel formation. FT-IR studies revealed that there was no chemical interaction between cephalexin and other excipients

Geotechnical Investigations for Foundation Design for Multi-storeyed Building

Oil and Natural Gas Commission of India plans to construct a multi-storeyed building in Dehradun city at the foothills of Himalayas. The geotechnical investigations were carried out at site to determine soil parameters for foundation design. It was found that it was not possible to provide a raft foundation for the building and hence alternatively the pile foundation was suggested. The pile load capacity was predicted on the basis of soil parameters determined and a comparison was then made with the results obtained by carrying out load tests on constructed piles

STATISTICAL DESIGN AND DEVELOPMENT OF A LIQUID ORAL FLOATING IN SITU GEL OF METFORMIN HYDROCHLORIDE FOR SUSTAINED RELEASE: PHARMACODYNAMIC AND TOXICITY (HISTOPATHOLOGY) STUDIES

Objective: To statistically design, optimize and evaluate a liquid oral, floating in situ gel of metformin hydrochloride (MH) to increase the gastric residence time (the absorption window being the upper part of the duodenum), sustain and modulate the release behavior of the drug. No liquid oral SR formulations of MH are yet available in the market. Methods: A simple mixing based ionic cross-linking method was used for the formulation. A Two-square Factorial Design was employed and the effect of sodium alginate and three categorical levels of HPMC (K4M, K100M, E50) on the response variables were studied. Results: The optimized formulation gelled instantaneously in simulated gastric fluid and showed>24 h floating. The drug release in 1h was 37.98 %, followed by a moderate sustained release for 12 h. Pharmacodynamic studies showed a significant reduction in blood glucose levels in Wistar rats. Short term preclinical safety studies revealed no toxicity to pancreatic tissues. On the contrary, faster regeneration of the β cells of the islets of Langerhans was observed with the group treated with the optimized formulation. Stability studies revealed a 2-year shelf life. Conclusion: An elegant, needle-free, in situ gelling, SR liquid oral of metformin hydrochloride could be developed with drug release modulated as per official specifications for SR formulations of MH. This would be an interesting alternative for geriatric patients who find it difficult to swallow bulky tablets

Hatchery production of Black-lip pearl oyster spat in the Andaman and Nicobar Islands: a success story

The lustrous black pearls produced by the black-lip pearl oysler Pinctada margaritifera in the inner surface its two shells have become one of the most valuable pearls on earth with prices ranging from a minimum of 100 US$and to a maximum of 10,000 US$ per pearl, in the case of those at exceptional and rare quality. Through the production of black pearls from Pinctada margaritifera, the island country of Tahili became the global leader in this business controlling 28.8% of the world market