Macro and microscopic characters of Maerua oblongifolia (Forssk.) A. Rich leaf

The paper deals with a detailed investigation on the leaves of Maerua oblongifolia (Forssk.) A. Rich. which includes it’s morphological, anatomical and powder analysis. It is a low woody bushy under-shrub belonging to the family Capparaceae. The leaves are used in treatment of as fever, ear ache, stomach ache, skin infections, urinary calculii, diabetes mellitus, epilepsy, rigidity in lower limbs, and abdominal colic. The leaf amphistomatic, with mostly anamocytic, few tetracytic stomata. In transverse section of leaf is ribbed on either sides at midvein, epidermis one layered. Mesophyll differentiated into palisade and spongy tissues. Ground tissue of midvein differentiated into palisade, collenchyma and parenchyma. The midvien consists of one large oval shaped vascular bundles arranged are at the centre. Petiole in transverse section is circular adaxially small, grooved at centre and epidermis is having one layered, a single circular vascular bundle present at the centre, vascular bundle is enclosed by endodermis. The powder microscopic and organoleptic characters are also presented in this study. This study would helps as an appropriate source for authentification of the present studied drug. &nbsp

EVALUATION OF DIFFERENT SYNTHETIC AND NATURAL POLYMERS AS PROTECTIVE LAYER ON HIGHLY SOLUBLE AND HIGH DOSE DRUG METOPROLOL SUCCINATEFOR MANUFACTURING OF CONTROL RELEASE MULTI UNIT PELLETS TABLETS

Objective: Evaluation of different natural and synthetic polymers as protective layer (PL) in the manufacturing of control release (CR) multi-unit pellets (MUPS) tablets, highly soluble and high dose drug metoprolol succinate (MS) was selected as model drug. The function of PL is to protect CR functional coating layer of pellets from damage during compression of MUPS tablets. Methods: MS is highly soluble biopharmaceutics classification system(BCS) Class–I molecule, hence selected aqueous solution layering method for drug loading in fluid bed processor (FBP), optimized formulation was manufactured by using seal coating on microcrystalline cellulose (MCC) pellets followed by drug loading (DL) and CR coating, applied by using the solution layering method in FBP. Given coating on these functional coated pellets with different natural and synthetic polymers like hydroxypropyl cellulose (Klucel LF), polyethylene glycol 6000 (PEG 6000), hypromellose 5 cps (HPMC 5cps), guar gum (GG) and xanthan gum (XM). Evaluated these pellet's for physical characterization and chemical characterization.Results: Drug release profiles of CR MUPS tablets containing PL coating were compared to those CR pellets and f2 values observed was 81.83, 49.92, 89.35, 66.44, and 85.25 with Klucel LF, PEG 6000, HPMC 5 cps, GG and XM coated MUPS tablets respectively. The dissolution data indicated that, there was no significant change were observed with MUPS containing Klucel LF, HPMC 5 cps, GG and XG PLs whereas faster release profiles were observed with PEG 6000PL MUPS tablets.Conclusion: Based on these dissolution profiles it was concluded that by applying low viscous natural or synthetic binders like Klucel LF, HPMC 5 cps, GG and XG on functional coating pellets given good protection to functional coating pellets from damage during compression. It is a very effective and potent strategy for manufacturing of MUPS tablets. Whereas PEG 6000 polymer not able to give protection to functional coating pellets from damage during compression, it may be due to its very low viscosity of PEG 6000

Esters of petroselinic acid containing Trachyspermum copticum seed oil: Potential industrial lubricant base stocks

126-134Trachyspermum copticum seed oil contains volatile oil rich in thymol, which is distilled out and used for medicinal and aromatic formulations. The seed powder after removal of the volatiles loses its importance. However, the fixed oil being rich in unsaturation with petroselinic acid (18:1, Δ6; 68.3%) and linoleic acid (18:2; 25.3%) is used for preparing biolubricant base stocks. Methyl, isopropyl and 2-ethyl hexyl esters of the oil have been converted to epoxides, followed by in situ hydroxylation and acylation using hexanoic and butyric anhydrides. The acylated products have been evaluated for lubricant properties, and are found to exhibit density (0.91-0.97 g/cc); viscosity of 23.5-27.3 cSt at 40°C and 4.85-5.33 cSt at 100°C. The values are comparable to jatropha acylated products. The products exhibited good copper corrosion resistance value of ‘1a’ and high flash points of 230-242°C. The acylated esters with good weld load behavior, and lower wear and pour point values and viscosity indices, 128.84-138.94, can be potential base stocks belonging to group III category lubricants with ISO VG Grade about 22. These products can be further explored for the preparation of hydraulic, metal working and other industrial fluid formulations

Hexagonal boron nitride tunnel barriers grown on graphite by high temperature molecular beam epitaxy

We demonstrate direct epitaxial growth of high-quality hexagonal boron nitride (hBN) layers on graphite using high-temperature plasma-assisted molecular beam epitaxy. Atomic force microscopy reveals mono- and few-layer island growth, while conducting atomic force microscopy shows that the grown hBN has a resistance which increases exponentially with the number of layers, and has electrical properties comparable to exfoliated hBN. X-ray photoelectron spectroscopy, Raman microscopy and spectroscopic ellipsometry measurements on hBN confirm the formation of sp2-bonded hBN and a band gap of 5.9 ± 0.1 eV with no chemical intermixing with graphite. We also observe hexagonal moiré patterns with a period of 15 nm, consistent with the alignment of the hBN lattice and the graphite substrate

Spin-Dependent Transport in Fe/GaAs(100)/Fe Vertical Spin-Valves

The integration of magnetic materials with semiconductors will lead to the development of the next spintronics devices such as spin field effect transistor (SFET), which is capable of both data storage and processing. While the fabrication and transport studies of lateral SFET have attracted greatly attentions, there are only few studies of vertical devices, which may offer the opportunity for the future three-dimensional integration. Here, we provide evidence of two-terminal electrical spin injection and detection in Fe/GaAs/Fe vertical spin-valves (SVs) with the GaAs layer of 50 nanometers thick and top and bottom Fe electrodes deposited by molecular beam epitaxy. The spin-valve effect, which corresponds to the individual switching of the top and bottom Fe layers, is bias dependent and observed up to 20 K. We propose that the strongly bias-and temperature-dependent MR is associated with spin transport at the interfacial Fe/GaAs Schottky contacts and in the GaAs membranes, where balance between the barrier profiles as well as the dwell time to spin lifetime ratio are crucial factors for determining the device operations. The demonstration of the fabrication and spin injection in the vertical SV with a semiconductor interlayer is expected to open a new avenue in exploring the SFET

Magnetic Behavior of Surface Nanostructured 50-nm Nickel Thin Films

Thermally evaporated 50-nm nickel thin films coated on borosilicate glass substrates were nanostructured by excimer laser (0.5 J/cm2, single shot), DC electric field (up to 2 kV/cm) and trench-template assisted technique. Nanoparticle arrays (anisotropic growth features) have been observed to form in the direction of electric field for DC electric field treatment case and ruptured thin film (isotropic growth features) growth for excimer laser treatment case. For trench-template assisted technique; nanowires (70–150 nm diameters) have grown along the length of trench template. Coercive field and saturation magnetization are observed to be strongly dependent on nanostructuring techniques