@article { ISI:000273174300036, title = {Novel/conceptual floating pulsatile system using high internal phase emulsion based porous material intended for chronotherapy}, journal = {AAPS Pharmscitech}, volume = {10}, number = {4}, year = {2009}, month = {DEC}, pages = {1368-1380}, publisher = {SPRINGER}, address = {233 SPRING ST, NEW YORK, NY 10013 USA}, abstract = {

The aim of the present study was to design a novel/conceptual delivery system using ibuprofen, anticipated for chronotherapy in arthritis with porous material to overcome the formulation limits (multiple steps, polymers, excipients) and to optimize drug loading for a desired release profile suitable for in vitro investigations. The objective of this delivery system lies in the availability of maximum drug amount for absorption in the wee hours as recommended. Drug loading using 3(2) factorial design on porous carrier, synthesized by high internal phase emulsion technique using styrene and divinylbenzene, was done via solvent evaporation using methanol and dichloromethane. The system was evaluated in vitro for drug loading, encapsulation efficiency, and surface characterization by scanning electron, atomic force microscopy, and customized drug release study. This study examined critical parameters such as solvent volume, drug amount, and solvent polarity on investigations related to drug adsorption and release mostly favoring low-polarity solvent dichloromethane. Overall release in all batches ranged 0.98-52\% in acidic medium and 71-94\% in basic medium. These results exhibit uniqueness in achieving the least drug release of 0.98\%, an ideal one, without using any release modifiers, making it distinct from other approaches/technologies for time and controlled release and for chronotherapy.

}, keywords = {chronotherapy, floating pulsatile drug delivery system, high internal phase emulsion, ibuprofen, multiparticulate porous carriers}, issn = {1530-9932}, doi = {10.1208/s12249-009-9331-1}, author = {Sher, Praveen and Ingavle, Ganesh C. and Ponrathnam, Surendra and Benson, James R. and Li, Nai-Hong and Pawar, Atmaram P.} } @article { ISI:000276061200012, title = {Ultrasound-triggered release of ibuprofen from a chitosan-mesoporous silica composite - a novel approach for controlled drug release}, journal = {Macromolecular Symposia}, volume = {287}, year = {2010}, note = {4th International Symposium on Macro-and Supramolecular Architectures and Materials, Dusseldorf, GERMANY, SEP 07-11, 2008}, month = {JAN}, pages = {80-88}, publisher = {Int Union Pure \& Appl Chem; German Res Fdn}, address = {PO BOX 10 11 61, D-69451 WEINHEIM, GERMANY}, abstract = {

In this work, an attempt was made to synthesize a novel Chitosan-Mesoporous silica (CS-MS) hybrid composite to design a drug delivery system based on ultrasound triggered stimuli-responsive smart release. The in-vitro drug release properties of both the Mesoporous Silica (MS) and Chitosan (CS) hybrids were investigated. Ibuprofen (Ibu) was used as a model drug. The results from powder X-Ray diffraction (XRD) patterns, and BET N(2) adsorption isotherms exhibited that MS can accommodate drug molecules into the lumen of the channels and pores. Drug release, stimulated by temperature and pH of the release media was also investigated. We studied the Ultrasound (US) triggered release of Ibu in a simulated body fluid (pH 7.4). The results exhibited that US can be used as a non-invasive technique for drug release from polymeric materials. The enhancing effect of ultrasound on drug release is due to the Cavitation effect, without causing any significant destruction on the polymer morphology.

}, keywords = {Chitosan, drug delivery systems, ibuprofen, Mesoporous silica, Ultrasound}, issn = {1022-1360}, doi = {10.1002/masy.201050111}, author = {Depan, Dilip and Saikia, Lakshi and Singh, Raj Pal} } @article { ISI:000306547300013, title = {Microstructural elucidation of self-emulsifying system: effect of chemical structure}, journal = {Pharmaceutical Research}, volume = {29}, number = {8}, year = {2012}, month = {AUG}, pages = {2180-2188}, publisher = {SPRINGER/PLENUM PUBLISHERS}, address = {233 SPRING ST, NEW YORK, NY 10013 USA}, abstract = {

Self-emulsifying systems (SES) emulsify spontaneously to produce fine oil-in-water emulsion when introduced into aqueous phase. The self-emulsification process plays an important role during formation of emulsion. The objective of current work was to understand and explore the inner structuration of SES through controlled hydration and further to study the influence of additive on the same which ultimately governs performance of final formulation in terms of droplet size. Droplet size of final formulations containing structural analogues of ibuprofen was determined. Microstructural properties of intermediate hydrated regimes of SES were investigated using techniques such as small angle X-ray scattering, differential scanning calorimetry and rheology. The current work established inverse relationship between droplet size of the formulations containing structural analogues of ibuprofen and their Log P values. Microstructural analysis of intermediate hydrated regimes of the prepared samples showed formation of local lamellar structure. Structural analogues of ibuprofen significantly altered microstructure of lamellae which was well correlated with the droplet size of final formulations. In vitro drug release study showed increase in dissolution rate of lipophillic drugs when formulated as SES. The current work emphasizes the fact that tailor-made formulations can be prepared by controlling the properties of intermediate regimes.

}, keywords = {emulsion, flurbiprofen, ibuprofen, ketoprofen, lamellar structure, self-emulsifying system, structural analogues}, issn = {0724-8741}, doi = {10.1007/s11095-012-0746-0}, author = {Patil, Sharvil S. and Venugopal, Edakkal and Bhat, Suresh K. and Mahadik, Kakasaheb R. and Paradkar, Anant R.} } @article { ISI:000363839500017, title = {Exploring microstructural changes in structural analogues of ibuprofen-hosted in situ gelling system and its influence on pharmaceutical performance}, journal = {AAPS Pharmscitech}, volume = {16}, number = {5}, year = {2015}, month = {OCT}, pages = {1153-1159}, publisher = {SPRINGER}, address = {233 SPRING ST, NEW YORK, NY 10013 USA}, abstract = {

The present work explores inner structuration of in situ gelling system consisting of glyceryl monooleate (GMO) and oleic acid (OA). The system under study involves investigation of microstructural changes which are believed to govern the pharmaceutical performance of final formulation. The changes which are often termed mesophasic transformation were analysed by small angle Xray scattering (SAXS), differential scanning calorimetry (DSC), rheology and plane polarised light (PPL) microscopy. The current work revealed transformation of blank system from W/O emulsion to reverse hexagonal structure upon addition of structural analogues of ibuprofen. Such transformations are believed to occur due to increased hydrophobic volume within system as probed by SAXS analysis. The findings of SAXS studies were well supported by DSC, rheology and PPL microscopy. The study established inverse relationship between log P value of structural analogues of ibuprofen and the degree of binding of water molecules to surfactant chains. Such relationship had pronounced effect on sol-gel transformation process. The prepared in situ gelling system showed sustained drug release which followed Higuchi model.

}, keywords = {flurbiprofen, hexagonal phase, ibuprofen, ketoprofen, liquid crystal, sustained drug release}, issn = {1530-9932}, doi = {10.1208/s12249-015-0308-y}, author = {Patil, Sharvil S. and Venugopal, Edakkal and Bhat, Suresh K. and Mahadik, Kakasaheb R. and Paradkar, Anant R.} }