Synthesis and Characterisation of Diaryl Furoxans

The paper discusses the synthesis, characterisation, and performance evaluation of diarylfuroxans namely, bis-phenyl-3,4-furoxan (5) and bis-(4’-nitrophenyl)-3,4-furoxan (6). Themolecules have been synthesised on the lines of reported method by cyclodimerisation of thenitrile oxides generated from benzaldoxime and p-nitro benzaldoxime, respectively. The synthesisedfuroxans (5 ) and (6) were characterised by the elemental analysis, UV, IR, and 1H NMRspectroscopy. The hazard characteristics (impact and friction sensitivity) confirm that thecompounds are safe to handle. The oxygen balance, velocity of detonation and detonationpressure have been computed. The detonation velocity and pressure along with oxygen balanceincreased with the substitution of nitro group in the benzene ring, as expected. Thethermogravimetric studies on promising compound (6) brings out that maximum weight lossoccurs at decomposition temperature of 259–260 °C

Higher order antibunching is not a rare phenomenon

Since the introduction of higher order nonclassical effects, higher order squeezing has been reported in a number of different physical systems but higher order antibunching is predicted only in three particular cases. In the present work, we have shown that the higher order antibunching is not a rare phenomenon rather it can be seen in many simple optical processes. To establish our claim, we have shown it in six wave mixing process, four wave mixing process and in second harmonic generation process.Comment: 6 pages, no figure, Latex 2

FORMULATION AND EVALUATION OF SUSTAINED RELEASE MATRIX TABLETS OF NATEGLINIDE

The objective of this work was to prepare and evaluate oral sustained release matrix tablet of Nateglinide and to study the effect of proportion of wax and addition of release liner on in-vitro release of drug.The prepared tablets were evaluated for pre and post compression parameters. Stability study of the promising formulation was also performed. The matrix tablets were prepared by Direct compression, Co-processed & melt granulation, method using wax in concentration 25%, 35% & 45% and evaluated for on in-vitro drug release using Compritol & Precirol. No interactions were found between drug and excipients. Formulation containing 25% Precirol F13 shows releases up to 12 hours. Tablets with release characteristics offers critical advantages such as site specificity with improved absorption and efficacy etc. Keywords: Nateglinide, Sustained release, Compritol 888, Precirol ATO 5, Melt Granulation, Direct compression

A MULTIPURPOSE AND NOVEL CARRIER FOR DRUG DELIVERY AND TARGETING - VIROSOMES

There is presently passionate investigation bustle aimed at the improvement of new delivery systems for vaccines. The aspiration is to identify best possible methods for presenting target antigens to the immune system in a manner that will elicit immune responses appropriate for protection against, or treatment of, a specific disease. Virosomes are biocompatible, biodegradable, nontoxic, and non-autoimmunogenic, attempts have been made to use them as vaccines or adjuvant as well as delivery systems for drugs, nucleic acids, or genes for therapeutic purposes. Influenza virus is the most common virus of choice. There are at present numerous factors that are creating pressure to develop delivery systems for vaccines. First, in the existing regulatory milieu, there is a budding prerequisite to build up vaccines that are very well defined in molecular requisites. Unambiguous targeting and liberation as well as the display of antigens on the surface of Professional antigen-presenting cells (APCs) are key issues in the blueprint and improvement of new-generation vaccines intended at the initiation of both humoral and cell mediated immunity. Prophylactic vaccination in opposition to infectious diseases in general aims at the generation of humoral immune responses to prevent infection. However, mmunization with live vaccines bears the peril of causing ailment. For that reason, unconventional vaccine delivery systems are must to produce better immune response. Virosomal technology presents a fresh urbane delivery system to congregate these challenges. On the whole, virosomes guard pharmaceutically active substances from proteolytic dilapidation and low pH within endosomes, allowing their contents to linger intact when they get in touch with the cytoplasm. This is a foremost benefit of virosomal transporter systems over other drug-delivery vehicles, including liposomal and proteoliposomal carrier systems.Â

A REVIEW ON MICROSPONGE DRUG DELIVERY SYSTEM

The drug delivery technology landscape has become highly competitive and rapidly evolving. More and more developments in delivery systems are being integrated to optimize the efficacy and cost-effectiveness of the therapy. Peptides, proteins and DNA-based therapeutics cannot be effectively delivered by conventional means. A Microsponges delivery system is a highly cross-linked, porous, polymeric microsphere, polymeric system consisting of porous microspheres that can entrap and release them into the skin over a long period of time. This delivery system provides extended release with reduced irritation, better tolerance, improved thermal, physical and chemical stability. The main goal of any drug delivery system is to achieve desired concentration of the drug in blood or tissue, which is therapeutically effective and non-toxic for a prolonged period In the present study various methods for preparation of microsponges drug delivery system are studied. Various advantages are also given which shows the importance of this method for the delivery of drugs over the other drug delivery system.  More and more developments in delivery systems are being integrated to optimize the efficacy and cost-effectiveness of the therapy. Microsponge technology offers entrapment of ingredients and is believed to contribute towards reduced side effects, improved stability, increased elegance, and enhanced formulation flexibility. In addition, numerous studies have confirmed that microsponge systems are non-irritating, nonmutagenic, non-allergenic, and non-toxic. Microsponges delivery technology is being used currently in cosmetics, over-the-counter (OTC) skin care, sunscreens and prescription products. One of the best feature of microsponge is it is self-sterilizing. This review is focused on method of preparation, characterization and application of microsponge. Keywords: Microsponge, Control relaease, Target release, topical formulation, oral administratio

Analysis of Genetic Diversity in Twelve Cultivars of Pea Based on Morphological and Simple Sequence Repeat Markers

Pea(Pisum sativum L.)is the second most important legume crop worldwide after chickpea (Cicer arietinum L.) and valuable resources for their genetic improvement. This study aimed to analyze genetic diversity of pea cultivars through morphological and molecular markers. The present investigation was carried out with 12 pea cultivars using 28 simple sequence repeat markers. A total of 60 polymorphic bands with an average of 2.31 bands per primer were obtained. The polymorphic information content, diversity index and resolving power were ranged from 0.50 to 0.33, 0.61 to 0.86 and 0.44 to 1.0 with an average of 0.46, 0.73 and 0.76, respectively. The 12 pea cultivars were grouped into 3 clusters obtained from cluster analysis with a Jaccardd's similarity coefficient range of 0.47-0.78, indicating the sufficient genetic divergence among these cultivars of pea. The principal component analysis showed that first three principal components explained 86.97% of the total variation, suggesting the contribution of quantitative traits in genetic variability. The contribution of 32.59% for number of seeds per plant, stem circumference, number of pods per plant and number of seeds per pod in the PC1 leads to the conclusion that these traits contribute more to the total variation observed in the 12 pea cultivars and would make a good parental stock material. Overall, this SSR analysis complements morphological characters of initial selection of these pea germplasms for future breeding program

Two-Level Atom in an Optical Parametric Oscillator: Spectra of Transmitted and Fluorescent Fields in the Weak Driving Field Limit

We consider the interaction of a two-level atom inside an optical parametric oscillator. In the weak driving field limit, we essentially have an atom-cavity system driven by the occasional pair of correlated photons, or weakly squeezed light. We find that we may have holes, or dips, in the spectrum of the fluorescent and transmitted light. This occurs even in the strong-coupling limit when we find holes in the vacuum-Rabi doublet. Also, spectra with a sub-natural linewidth may occur. These effects disappear for larger driving fields, unlike the spectral narrowing obtained in resonance fluorescence in a squeezed vacuum; here it is important that the squeezing parameter $N$ tends to zero so that the system interacts with only one correlated pair of photons at a time. We show that a previous explanation for spectral narrowing and spectral holes for incoherent scattering is not applicable in the present case, and propose a new explanation. We attribute these anomalous effects to quantum interference in the two-photon scattering of the system.Comment: 10 pages, 17 figures, submitted to Phys Rev

FABRICATION DEVELOPMENT, OPTIMIZATION AND CHARACTERIZATION OF GASTRORETENTIVE MICROSPHERES OF AN ANTIHYPERTENSIVE DRUG

The objective of the present study was to develop floating microspheres of Captopril in order to achieve an extended retention in the upper GIT which may enhance the absorption and improve the bioavailability. In the present study, preparation of captopril floating microspheres, evaluation of Floating Drug Delivery System (FDDS) in vitro, forecast of the release, and optimization of stirring speed and polymers ratio to match target release profile was investigated. The microspheres were prepared by solvent evaporation method using different ratio of hydroxyl propyl methyl cellulose (HPMC K4M) with drug in the mixture dichloromethane and ethanol at ratio of (1:1), with tween80 as the surfactant. Differential Scanning Calorimeter (DSC) study shows that drug and other excipients are compatible with each other. The effects of polymers concentration on drug release profile were investigated. The floating microspheres were characterized by and results obtained are % yield, particle size analysis, drug entrapment efficiency, surface topography, buoyancy percentage, in-vitro drug release was studied for 12 hour and scanning electron microscopy. Accelerated stability study was also performed for three months indicated that optimized formulation was stable. The floating microspheres showed better result and it may be use full for prolong the drug release in stomach and improve the bioavailability. The outcome showed that the polymer ratio and stirring speed affected the size, incorporation efficiency and drug release of microspheres (> 12 h), floating time (> 12 hr) and the best results were obtained at the ratio of HPMC K4M: EC (1:6). The mean particle size of prepared floating microspheres increased but the drug release rate from the microspheres decreased as the polymer concentration increased. The developed floating microspheres of captopril may be used for prolonged drug release for at least 12 hrs, thereby improving the bioavailability and patient compliance. Key words: Floating microspheres (FDDS), captopril, hydroxyl propyl methyl cellulose, ethyl cellulose, in-vitro release studies, bioavailability