Sahu D.K.,Indian Institute of Astrophysics |
Anupama G.C.,Indian Institute of Astrophysics |
Chakradhari N.K.,Pandit Ravishankar Shukla University
Monthly Notices of the Royal Astronomical Society | Year: 2013
Optical UBVRI photometry and low-resolution spectroscopy of the Type IIb supernova SN 2011dh in M51 are presented, covering the first year after the explosion. The light curve andspectral evolution are discussed. The early phase light-curve evolution of SN 2011dh is verysimilar to SN 1993J and SN 2008ax. In the late phase, however, SN 2011dh declines faster thanSN 1993J. The late phase decline in the B band is steeper than in the R and I bands, indicatingthe possibility of dust formation. With a peak V-band absolute magnitude of MV =-17.123±0.18 mag, SN 2011dh is a marginally faint type IIb event. The reddening corrected colourcurves of SN 2011dh are found to be redder than other well-studied Type IIb supernovae. Thebolometric light curve indicates ~;0.09Mȯ of 56Ni is synthesized during the explosion. TheHe I lines were detected in the spectra during the rise to maximum. The nebular spectra ofSN 2011dh show a box-shaped emission in the red wing of the [OI] 6300-6363Å feature, that is attributed to Hα emission from a shock-excited circumstellar material. The analysis ofnebular spectra indicates that ~0.2Mȯ of oxygen was ejected during the explosion. Further, the [Ca II]/[O I] line ratio in the nebular phase is ~0.7, indicating a progenitor with a mainsequence mass of 10-15Mȯ. © 2013 The Authors Published by Oxford University Press on behalf of the Royal Astronomical Society.
Verma S.K.,Pandit Ravishankar Shukla University |
Ghosh K.K.,Pandit Ravishankar Shukla University
Journal of Surfactants and Detergents | Year: 2011
The physicochemical and interfacial properties of the monomeric surfactants cetyltrimethyl ammonium bromide (CTAB), cetyltriphenyl phosphonium bromide (CTPB), tetradecyl triphenyl phosphonium bromide (TTPB), cetyldiethylethanol ammonium bromide (CDEEAB), cetyltrimethyl ammonium chloride (CTACl), tetradecyltrimethyl ammonium bromide (TTAB), and a gemini surfactant (C16-3-C16, 2Br-) at different pH (3.1, 7.0, and 7.75) have been investigated by conductivity and surface tension measurements at 300 K. The critical micellar concentration (CMC), degree of micellar ionization (a), surface excess concentration (Umax), minimum surface area per molecule of surfactant (Amin), Gibbs free energy of micellization (ΔGm 0 ), surface pressure at the CMC (pCMC), and the Gibbs energy of adsorption (ΔGads 0 ) of the monomeric surfactants have also been determined. The CMC, a and Umax, increase with increasing pH whereas Amin decreases. © AOCS 2011.
Gidwani B.,Pandit Ravishankar Shukla University |
Vyas A.,Pandit Ravishankar Shukla University
Colloids and Surfaces B: Biointerfaces | Year: 2014
Cyclodextrins, the macrocyclic compounds are renowned for their inclusion ability. Several chemical and polymerized derivatives of parent cyclodextrins are synthesized to improve the physicochemical/biopharmaceutical properties of drug and inclusion capacity of cyclodextrin. This review article recapitulates the potential aspects of polymerized water-soluble derivative of β-cyclodextrin viz. epichlorohydrin-β-cyclodextrin polymer in different areas of drug delivery. Polymerized cyclodextrin combines the advantage of the properties of polymer (high molecular weight and higher solubility) with the formation of inclusion complex with cyclodextrin. This justifies the superiority of polymerized cyclodextrin over parent cyclodextrin and some other chemically modified and non-polymerized derivatives. The use of polymerized cyclodextrin in various fields like biomedical, pharmaceutical and gene delivery is increasing day-by-day. β-Cyclodextrin-epichlorohydrin polymer is a high molecular weight compound, which acts as an effective drug carrier for enhancing the solubility and oral bioavailability of drugs along with the increase in therapeutic efficiency. The future panorama of polymerized cyclodextrins is quite bright as they can serve as useful multifunctional tools for pharmaceutical scientists to develop and optimize drug delivery through various routes. Also, no information concerning the regulatory status and toxicity of polymerized cyclodextrins is available. So, there is a need to focus on these critical issues for resolving the problems associated with the development and commercialization of drug products. © 2013 Elsevier B.V.
Kaur C.D.,Pandit Ravishankar Shukla University |
Saraf S.,Pandit Ravishankar Shukla University
Journal of Cosmetic Dermatology | Year: 2011
Background Ultraviolet radiations generate reactive oxygen species, leading to adverse effects on skin properties. Botanical extracts are multifunctional in nature having various properties like photoprotection, anti-aging, moisturizing, antioxidant, astringent, anti-irritant, and antimicrobial activity. Aims The aim of this study was to formulate creams having Curcuma longa extract loaded novel vesicular systems (liposomes, ethosomes, and transfersomes) and study their photoprotective effect by assessment of skin hydration (Cutometer) and sebum content (Sebumeter). Methods The alcoholic C. longa extract loaded liposomes, ethosomes, and transfersomes having 0.5-2.0% w/w extract were prepared, evaluated for size, entrapment efficiency, and incorporated into the cream. Their long-term interaction with skin (6weeks) was compared in terms of their effects on skin hydration and sebum content. Results Vesicular size obtained was in the range 167.3±3.0 to 262.4±2.4nm with low polydispersity index (0.2-0.3) and high entrapment efficiency. The efficacy was in the order C. longa extract loaded transfersomal creams > C. longa extract loaded ethosomal creams > C. longa extract loaded liposomal creams > C. longa extract loaded creams > Empty transfersome loaded cream > Empty ethosome loaded cream > Empty liposome loaded cream > Base cream. Conclusions The photoprotective properties of the constituents of C. longa extract and hydrant, moisturizing lipid components of nano vesicles with better skin penetration resulted in improvement in skin properties like skin hydration and sebum content. The herbal extract loaded nano vesicles incorporated in cream could be used as photoprotective formulations. © 2011 Wiley Periodicals, Inc.
Saraf S.,Pandit Ravishankar Shukla University
Journal of cosmetic science | Year: 2012
Botanical photochemoprotectives are used because they act on various stages to prevent skin cancer and photoaging. The aim of this study was to prepare herbal creams from various photochemoprotective herbs and to perform efficacy studies on them by using physicochemical, microbiological, safety, psychometric, biophysical, and sun protection factor measurements. Herbal creams were prepared by incorporating hydroalcoholic extracts of Curcuma caesia (rhizome), Areca catechu (seeds), Centella asiatica (leaves) Cinnamon zeylanicum (dried bark), and Tamarindus indica (fruit pulp) in varied concentrations (1-5% w/w) in a base cream. The efficacy of all formulations was checked out for four weeks on 60 normal subjects on the volar forearm for evaluation of biophysical properties, and for psychometric evaluations (fragrance, lathery feel, softness, irritation, stickiness, smoothness, and aftereffect on the skin) and safety measurements. In the biophysical characterization, a cutometer for viscoelasticity, a mexameter for melanin content, a corneometer for hydration, and a sebumeter for sebum determination were used. All the cream formulations with 1% and 3% w/w extracts showed positive results and passed physicochemical, microbiological, and safety tests. The SPF values increased as the concentration of extract was increased up to a limit in the formulations. The SPF values were significantly higher (p < 0.01) in formulations with 3% herbal extract than with 1% herbal extract. Increased skin hydration, sebum levels, viscoelasticity, and decreased melanin values were obtained. The Cinnamon, Centella, and Tamarindus formulations were found more effective as photoprotectives than the Areca and Curcuma formulations.
Suresh P.K.,Pandit Ravishankar Shukla University |
Sah A.K.,Pandit Ravishankar Shukla University
Expert Opinion on Drug Delivery | Year: 2014
Introduction: Many therapeutic strategies have been adopted in the treatment of anterior uveitis, and it includes corticosteroids and NSAIDs. But, the successful delivery of these drugs is restricted due to limitations of conventional formulation. This review emphasizes on the possible benefits and strategies for development of various novel nanocarriers.Areas covered: The article explores the various polymers involved in the preparation of novel nanocarriers like polymeric nanoparticles, micelles, microemulsion, liposomes and cubosomes. Reported clinical experimental findings are screened and also discussed in this review.Expert opinion: The principle behind the development of different nanocarriers is to overcome the limitations imposed by conventional formulations. Several efforts have been made by the researchers in achieving these objectives, but the major challenge with nanosystems remains the requirement of excipients that have unknown or objectionable toxicity profile and are not approved by regulatory authorities. This review is an attempt to provide comprehensive information for the scientists working in the concerned research area. © 2014 Informa UK, Ltd.
Deepmala,Pandit Ravishankar Shukla University |
Pathak H.K.,Pandit Ravishankar Shukla University
Acta Mathematica Scientia | Year: 2013
In this paper, we prove the existence of solutions of some nonlinear functional-integral equation by using a fixed point theorem which satisfy the Darbo condition. The results extend the corresponding results of many authors. In the sequel, we give an example of our main result to highlight the realized improvements. © 2013 Wuhan Institute of Physics and Mathematics.
Vyas A.,Pandit Ravishankar Shukla University
Journal of Inclusion Phenomena and Macrocyclic Chemistry | Year: 2013
In the present study influence of nature of selected cyclodextrins (CDs) and of methods of preparation of drug-CD complexes on the oral bioavailability, in vitro dissolution studies and pharmacodynamic activity of a sparingly water soluble drug rosuvastatin (RVS) was investigated. Phase solubility studies were conducted to find the interaction of RVS with β-CD and its derivatives, which indicated the formation of 1:1 stoichiometric inclusion complex. The apparent stability constant (K1:1) calculated from phase solubility diagram were in the rank order of β-CD < hydroxypropyl-β- cyclodextrin (HP-β-CD) < randomly methylated-β-cyclodextrin (RM-β-CD). Equimolar drug-CD solid complexes prepared by different methods were characterized by the Fourier transform infrared spectroscopy (FTIR), differential scanning calorimetry (DSC) and X-ray diffractometry (XRD). FTIR study demonstrated the presence of intermolecular hydrogen bonds and ordering of the molecule between RVS and CDs in inclusion complexes. DSC and XRD analysis confirmed formation of inclusion complex by freeze dried method with HP-β-CD and RM-β-CD. Aqueous solubility and dissolution studies indicated improved dissolution rates of prepared complexes in comparison with drug alone. Moreover, CD complexes demonstrated of significant improvement in reducing total cholesterol and triglycerides levels as compared to pure drug. However the in vivo results only partially agreed with those obtained from phase solubility studies. © 2012 Springer Science+Business Media B.V.
Das S.,Narsee Monjee Institute of Management and Higher Studies |
Suresh P.K.,Pandit Ravishankar Shukla University
Nanomedicine: Nanotechnology, Biology, and Medicine | Year: 2011
Present limitations in the management of ophthalmic fungal infections include the inability to provide long-term extraocular drug delivery without compromising intraocular structures and/or systemic drug exposure. In the present study, the potential of Eudragit RS 100 nanoparticles (NPs) as a new vehicle for the improvement of the delivery of drugs to the ocular mucosa was investigated. Amphotericin B (AmB) was chosen as a model compound because of its potential usefulness for the treatment of fungal diseases. A solvent displacement technique was used to produce AmB-loaded Eudragit NPs. These NPs had a mean size range of 150-290 nm and a zeta potential of +19-28 mV. Even after 6 months of stability study, results were unchanged, indicating the good potential for ocular application. In vitro release studies revealed that a maximum amount of drug was released within 24 hours (60%). The results obtained from microbial assay showed that the antifungal activity of drug-loaded NPs was equal to or slightly lower than that of free-AmB solution. In vivo experiments showed that, following topical instillation of nanosuspension to a rabbit's eye there was no irritation. From these results we can conclude that Eudragit RS 100 nanosuspension may represent an efficacious vehicle to deliver the drug into the eye. From the Clinical Editor: Amphotericin B encapsulated into Eudragit, a mildly cationic nanoparticle, was shown to have 6 month stability, release 60% of its drug payload in dissolution within 24 hours, and elicited no irritation when instilled into rabbit eyes. The concept is being considered for local ophthalmologic therapy of fungal disease. © 2011 Elsevier Inc.
Tamrakar R.K.,Bhilai Institute of Technology |
Bisen D.P.,Pandit Ravishankar Shukla University
AIP Conference Proceedings | Year: 2013
The Ceria doped Gadolinium (Gd2O3) nanopowder was synthesized by combustion synthesis by using urea as a fuel. The combustion synthesis method which is reported here is advantageous from the perspectives of small size of the nanoparticle. The structural and photoluminescence (PL) property of sample was studies. Gd2O3:Ce3+ nanoparticles exhibit green emission around 543 nm. The result of XRD show that synthesized sample has cubic structure. The average size of particle is found to be 45 nm. The surface morphology of the films is also presented. © 2013 AIP Publishing LLC.