Paying Obeisance to the Humble “Coconut”: A Short Commentary

Short commentary on the occasion of World Coconut Day, celebrated on 2nd September every yea

Novel Catalytic Materials for Selective Oxidation of Carbon Monoxide for Use in Fuel Cells

The present work includes the preparation, characterisation and testing of alumina supported Pt-based bimetallic catalysts for the selective removal of carbon monoxide in the presence of excess hydrogen, to be used as the feed stock for fuel cells. In this study, an attempt has been made to modify the Pt/Al203 (low- and high-dispersed) catalyst with Sn, Fe, Co, Cr, Mn, Ni and Cu as promoters using the surface organometallic chemistry (SOMC) route. Various techniques have been employed to characterise the Pt/Al2O3 and the M-Pt/Al2O3 bimetallic catalysts. Inductively Coupled Plasma - Atomic Emission Spectroscopy (ICP-AES) technique has been used to determine the composition of the promoted catalysts. The presence of the expected amounts of the second metal in the bimetallic catalysts indicated success of the SOMC route for the preparation of the bimetallic catalysts. The CO uptake by bimetallic catalysts has been found to be lower than that by Pt/AEO] catalyst. Decrease in the CO uptake during CO chemisorption experiments relative to the basic Pt/Al203 catalyst indicates the physical presence of the second metal on the Pt sites suggesting a selective reaction between the reduced surface Pt of the Pt/Al203 catalyst and the organometallic precursor of the second metal had occurred. The shift in the reduction peaks for the bimetallic catalysts in the Temperature Programmed Reduction (TPR) profile compared with that of unpromoted catalyst suggested physical proximity of the two metal species in the catalyst. The presence of the two metals together with no observable change in the size of the particles in the bimetallic catalysts has been confirmed by using Transmission Electron Microscopy (TEM/STEM) together with Energy Dispersive X-Ray (EDX) analysis. This was yet another proof of successful deposition of second metal on Pt by the SOMC technique. All the M-Pt/Al203 bimetallic catalysts (low-dispersed) prepared by the SOMC route were screened towards CO oxidation in the presence of excess H2. Out of all the bimetallic catalysts screened, the best performing catalysts were chosen for the detailed study using two different gas mixtures, containing 02:C0 ratios of 2.5 and 1. The most interesting feature of this study was the performance of Fe- and Co-promoted catalysts under different O2:CO ratios. Both the systems, FePt and CoPt, brought the temperature for the complete CO oxidation down to the temperature range of 80 - 100 °C which is highly preferred for the commercial applications, while maintaining the high value of CO selectivity. The enhanced activity of the promoted Pt catalysts was suggested to be due to the presence of a metal oxide, MOx (M = Fe and Co) which provides the site for O2 absorption and dissociation and therefore eliminates the normal inhibition observed in the oxidation of CO on Pt catalysts

DESIGNING AND OPTIMIZATION OF NAPROXEN SODIUM DEFORMABLE VESICULAR SYSTEMS THROUGH FACTORIAL DESIGN: BOX BEHENKEN MODEL

Objective: The objective of this investigation was to develop and statistically optimize deformable vesicles such as transfersomes and transethosomes of Naproxen sodium by employing 33factorial designs through software Design expert version 12 (Box–Behnken design) for dermal delivery. Methods: The levels of the drug, phosphatidylcholine, and span 80 (independent variables) were varied to study the influence on vesicle size and % entrapment efficiency (dependent variables) of transfersomes and for transethosomes, the levels of phosphatidylcholine, ethanol, and span 80 were selected as independent variables Second-order quadratic polynomial equation, 2D and 3D contour plots represented the relationship between variables and desired response. The optimization process was carried out using desirability plots and point prediction techniques. Results: Results of the present study demonstrated that optimized transfersomes and transethosomes showed vesicle sizes of 114.91 nm and 102.91 nm respectively, while entrapment efficiency of 80.11 % and 86.97%, respectively. Both formulations showed high zeta potential values indicating the stability of the optimized formulation. ANOVA statistical results showed a significant difference (P<0.05). Conclusion: The results indicated that the independent variable plays a crucial role in optimizing a formulation that can be used for further research studies. Present preliminary study data provided strong evidence that the optimized deformable vesicular formulations through box Behnken factorial design can be a potentially useful drug carrier for naproxen sodium dermal delivery with minimum vesicle size and efficient entrapment efficiency

Bioadhesive or Mucoadhesive Drug Delivery System: A Potential Alternative to Conventional Therapy

The term bioadhesive describes materials that bind to biological substrates, such as mucosal membranes and in bioadhesive drug delivery systems, the term bioadhesion is used to describe the bonding or adhesion between a synthetic or natural polymer and soft tissues such as epithelial cells. The bioadhesive drug delivery formulation highlights the fact that readily accessible sites are utilized with the eye, oral cavity and vegina being targeted. The GI tract and the nasal cavity have also been extensively examined as a site for bioadhesive drug delivery. The term mucoadhesion is the subgroup of bioadhesion and in the mucoadhesion formulation attaches with the mucus membrane. The mucoadhesion can be defined as the adhesion between the two materials in which one is biological material and other one is polymeric materials with the help of interfacial forces to increase the residence time. Over the past few decades, mucosal drug delivery has received a great deal of attention. The mucoadhesion drug delivery system is better than the traditional drug delivery systems. Mucoadhesion is a useful strategy for drug delivery systems, such as tablets, patches, gels, liposomes, micro/nanoparticles, nanosuspensions, microemulsions and colloidal dispersions. The mucoadhesion bypasses the first pass metabolism and used for localized delivery of biomolecules such as peptides, proteins and oligonucleotides. Mucoadhesion drug delivery system engages much attention due to their benefits such as prolong retention time, fast uptake and increased bioavailability of active substance. Application of dosage forms to mucosal surfaces may be of benefit to drug molecules not amenable to the oral route, such as those that undergo acid degradation or extensive first-pass metabolism. The mucoadhesive ability of a dosage form is dependent upon a variety of factors, including the nature of the mucosal tissue and the physicochemical properties of the polymeric formulation. This review article aims to provide an overview of the various aspects of mucoadhesion, theories of mucoadhesion, mucoadhesive materials, factors affecting mucoadhesion, evaluating methods, mucoadhesive polymers and herbal drugs. Keywords: Bioadhesive, bioadhesive drug delivery, Mucoadhesion, Patches, Herbal drug

An Overview on Phyto-molecules and Screening Method of Antiurolithiatic Activity

Kidney stones are one of the oldest known and common diseases in the urinary tract system. Kidney stones are a growing global problem. It is also known as Urolithiasis. Lithiasis is a condition where urinary calculus is formed in the kidney and urinary tract. It is a complicated urinary disorder that has gravely troubled the health and quality of human life. It has been associated with an increased risk of end-stage renal failure. Urinary stones affect 10-12% of the population in industrialized countries. There are only a few geographical areas in which the stone disease is rare, e.g., Germany and in the coastal areas of Japan. The etiology of kidney stone is multifactorial. The most common type of kidney stone is calcium oxalate formed at Randall’s plaque on the renal papillary surfaces. The mechanism of stone formation is a complex process which results from several physicochemical events including supersaturation, nucleation, growth, aggregation and retention of urinary stone constituents within tubular cells. These steps are modulated by an imbalance between factors that promote or inhibit urinary crystallization. Currently, there is no satisfactory drug to cure and/or prevent kidney stone recurrences.  Conventional agents are being used to control kidney stone along with lifestyle management.  Medicinal plants are found to be useful in this metabolic disorder from ancient days due to its no or low-toxic nature, easily available in rural areas, cheap; there are fewer chances of recurrence. Thus, further understanding of the pathophysiology of kidney stone formation is a research area to manage urolithiasis using new drugs. Therefore, this review has intended to provide compiled up-to-date information on kidney stone etiology, pathogenesis and prevention approaches and critically review the available literature on various medicinal plants with their antilithiatic activity and screening method of this activity to develop an effective drug to treat the disease. Keywords: Kidney stones, Urolithiasis, Etiology, Calcium oxalate, Pathophysiology, Medicinal plant

Spintronics: Combination of Nanotechnology & Superconductivity

Advances in fabrication & characterization of magnetic & superconductivity materials on nanometre length scales paves the way for new experimental, theoretical & technological frontiers. This paper emphasize on “spintronics”:  it is a nanoscale technology in which information is carried not by the electon’s charge, as it is in conventional microchips, but by the electron’s intrinsic spin, by controlling the spin degree of freedom in solid – state heterostructures & magnetic quantum  dots,  Spintronics  offers new possibilities for developing data processing speeds, lower electric consumption & the ability to carry out radically new quantum computations over conventional electronics. Spintronics a prototype device that is already in use in industry as a read head & a memory –storage cell is the giant – magneto resistive (GMR) sandwich structure which consists of alternating ferromagnetic & non-magnetic metal layers. Experimental work is reviewed with the emphasis on the fundamentals & application in which external electric & magnetic field will be used to control spin & charge dynamics to create new functionalities which are ineffective with conventional electronics. Key Words: spintronics,  superconductivity,  giant – magneto resistive (GMR),  magnetic field,  heterostructures,  conventional electronics etc

A Survey: Spider Monkey Optimization Algorithm

Swarm intelligence is a one of the areas for evaluating the optimization states. Many algorithms have been developed by simulating the swarming behaviour of various creatures like ants, honey bees, fishes, birds and their results are found as very motivating for solving optimization problems. In this paper, a new approach for optimization is proposed by modelling the social behaviour of spider monkeys. Spider monkeys have been categorized as fission-fusion social structure based animals. The animals which follow fission-fusion social systems, initially work in a large group and based on need after some time, they divide themselves in smaller groups led by an adult female for foraging. There- fore, the proposed strategy broadly classified as inspiration from the intelligent foraging behaviour of fission-fusion social structure based animals

Formulation and Evaluation of Extended Release Floating Matrix Tablet of Eperisone Hydrochloride by Direct Compression Method

Increased complications and costs of marketing of innovative drugs focused greater attention to the development of sustained release (SR) or controlled release (CR) drug delivery systems. Delivery systems extended release or controlled release rate can achieve predictable and reproducible, the extended duration of activity for the short time of life - drugs, reduced toxicity and dose reduction request, the optimized therapy and better patient compliance. It is controlled primarily by the type and the proportion of the polymers used in the preparation. Eperisone hydrochloride is a centrally acting muscle relaxant acting through poly and mono-synaptic reflexes in the spinal cord, exhibits vasodilator effect, increases blood flow and inhibits the pain reflex pathway. The objective of present work was to develop and evaluated oral extended release floating matrix tablet of eperisone HCl prepared by the method of direct compression, using hydroxy propyl methyl cellulose (HPMC K15, HPMC K4) and PVP K30 as matrix formation polymers. Sodium bicarbonate and citric acid was used as gas generating agents. The FTIR spectra of the eperisone HCl and other excipients alone and in combination show the compatibility of the drug and excipients. Nine formulations of different polymer percentages were formulated (F1-F9). Pre-compression parameters were evaluated. The influence of matrix forming agents and binary mixtures of them on eperisone HCl release was investigated. The formulated tablets were characterized by thickness and diameter, drug content, hardness, friability, uniformity of weight, In vitro buoyancy studies and dissolution rate studies. The formulated tablets had acceptable physicochemical characters. The data obtained from the in-vitro dissolution studies of optimized batch F7 were fitted in different models. The optimized formulation F7 showed 99.45±0.45% drug content and floating lag times of 65±4 sec. Drug release mechanism was found to be first order kinetics. Eperisone HCl floating tablets exhibited increased gastric residence time, there by improved bioavailability and therapeutic effect of the drug. Keywords: Sustained release, Eperisone hydrochloride, Direct compression, Pre and post compression parameter

Preparation, Characterization and Evaluation of Silver Nanoparticles of Thunbergia Grandiflora and Its Antimicrobial Activity

Nanoparticles are gaining interest in biomedical applications due to its importance such as anti-bacterial, anti-fungal and anti-cancer agents. A conventional method for the synthesis of metal nanoparticles involves toxic reagents which produce harmful by-products and are hazardous to the environment. To overcome these limitations, green synthesis of nanoparticles was established. Eco-friendly methods using plant extracts are gaining popularity due to the abundance of raw materials and the production of non-toxic by-products threatening to the environment. Moreover, the nanoparticles synthesized from the plant extract are cost-effective. In addition, nanoparticles produced by green synthesis methods produce synergetic effect where both the nanoparticles as well as the natural bioactive constituents of the plant influence the biocidal properties. The present investigation evaluates phytochemical screening, antimicrobial, antioxidant activities and green synthesis, characterization of silver nanoparticles and its antimicrobial activity. Three dissimilar solvents viz., petroleum ether, ethyl acetate and methanol were used to prepare crude extracts of T. grandiflora leaves.  Antioxidant activity was examined by means of DPPH and reducing power assay method. AgNPs were synthesized by using 1mM AgNO3 solution mixed with leaf aqueous extract of T. grandiflora. The characterization of the prepared AgNPs was done by UV-Vis spectrometry and FTIR spectroscopy. Antimicrobial activity was studied by agar well diffusion method. The phytochemical screening results unveiled the bearing of different phytochemicals viz., flavonoids, alkaloids, saponins, carbohydrates, terpenoids, steroids, tannins and free anthraquinones particularly with relatively high abundance in methanol extract. The total phenolics content of leaves of methanolic extract was (0.058mg/gm), followed by flavonoids (1.080mg/gm).  Likewise methanol extract too exhibited effective free radical scavenging and antimicrobial activities were concentration dependent. The characterization results of the prepared AgNPs displayed that the silver nanoparticles are formed and stabilized by plant phyto-constituents and also exhibited virtuous antimicrobial property. Green synthesis process is a pivotal area in nanotechnology and usage of natural resources is the best choice for the making of NPs as a sustainable, eco-friendly, inexpensive and free of chemical contaminant method

Formulation, Development and Evaluation of Fast Dissolving Oral Film of Antipsychotic Drug

In case of psychiatric treatment immediate release of drug from the dosage form is required. Fast dissolving dosage forms are gaining popularity in recent time, as this dosage forms requires no water for administration. Oral films dissolve rapidly along with drug in mouth and majority of the drug is absorbed through buccal/oral mucosa in to systemic circulation avoiding first pass metabolism. Olanzapine is a thienobenzodiazepine class of drugs, which has been approved by the FDA, for the treatment of schizophrenia, depressive episodes associated with bipolar disorder, acute manic episodes and maintenance treatment in bipolar disorder. The absolute bioavailability is only approximately 31.5% due to extensive hepatic metabolism. Thus the objective of the present study was to formulate and evaluate fast dissolving oral films of Olanzapine to improve water solubility, dissolution rate, oral bioavailability and reduction of first pass metabolism and increase patient’s compliance. Oral fast dissolving films prepared by solvent casting method using water and 95% ethanol as solvents and HPMC as film forming polymer. PEG 400 was the selected plasticizers, Superdisintegrants such as croscarmellose sodium (CCS) and sodium starch glycolate (SSG) alone and also in combinations was incorporated to achieve the aim. The prepared films were evaluated for the drug content, weight variation, film thickness, disintegration time, folding endurance, percentage of moisture content and in vitro dissolution studies. Among all, the formulation F4 was found to be best formulation which releases 98.78 % of the drug within 15 min and disintegration time is 42 sec. which was significantly high when compared to other formulation. The data obtained from In-vitro release were fitted into the various kinetic models such as Zero Order, Higuchi, First Order and Korsmeyer–Peppas Model in order to determine the mechanism of drug release. When the regression coefficient values compared, it was observed that ‘r’ values of formulation F4 was maximum i.e 0.974 hence indicating drug release from formulations was found to follow first order drug release kinetics. &nbsp