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An accurate, simple, fast, and cheap spectrophotometric method has been developed for the determination of lisinopril in pharmaceutical pure and dosage forms. The method is based on the reaction of ninhydrin with primary amine present in the lisinopril in the presence of DMF. This reaction produces a greenish blue colored product which absorbs maximally at 600 nm. Beer's law was obeyed in the range of 10-150 mg/mL with molar absorptivity of 4.083´10 3 L mole -1 cm -1 . The effects of variables such as temperature, heating time, concentration of color producing reagent, and stability of color were investigated to optimize the procedure. The results are validated statistically. The proposed method was applied to commercially available tablets, and the results were statistically compared with the official potentiometric method.

Corrosion and heat treatment studies are essential to predict the performance and sustainability of the coatings in harsh environments, such as the oil and gas industries. In this study, nickel phosphorus (NiP)–titanium (Ti) nanocomposite coatings (NiP-Ti nanoparticles (TNPs)), containing various concentrations of Ti nanoparticles (TNPs) were deposited on high strength low alloy (HSLA) steel through electroless deposition processing. The concentrations of 0.25, 0.50 and 1.0 g/L TNPs were dispersed in the electroless bath, to obtain NiP-TNPs nanocomposite coatings comprising different Ti contents. Further, the effect of TNPs on the structural, mechanical, corrosion, and heat treatment performance of NiP coatings was thoroughly studied to illustrate the role of TNPs into the NiP matrix. Field emission scanning electron microscope (FESEM) and energy dispersive spectroscopy (EDX) results confirm the successful incorporation of TNPs into the NiP matrix. A substantial improvement in the mechanical response of the NiP matrix was noticed with an increasing amount of TNPs, which reached to its ultimate values (hardness 675 Hv, modulus of elasticity 18.26 GPa, and stiffness 9.02 kN/m) at NiP-0.5TNPs coatings composition. Likewise, the electrochemical impedance spectroscopy measurements confirmed a tremendous increase in the corrosion inhibition efficiency of the NiP coatings with an increasing amount of TNPs, reaching ~96.4% at a composition of NiP-0.5TNPs. In addition, the NiP-TNPs nanocomposite coatings also unveiled better performance after heat treatment than NiP coatings, due to the presence of TNPs into the NiP matrix and the formation of more stable (heat resistant) phases, such as Ni3P, Ni3Ti, NiO, etc., during the subsequent processing.

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Citalopram is a highly selective serotonin (5-hydroxytryptamine, 5-HT) reuptake inhibitor (SSRI) with minimal effects on the neuronal reuptake of norepinephrine and dopamine. It is a bicyclic phthalane derivative (racemic), which is not related to the tricyclic or tetracyclic antidepressants. It is used in the treatment of major depressive disorder. The hydrobromide salt of it is administered orally. Chemically, it is (Ϯ)-1-(3-dimethylaminopropyl)-1-(4-fluorophenyl)-1,3-dihydroisobenzofuran-5-carbonitrile, hydrobromide. 1)A very few analytical methods appeared in the literature for the determination of citalopram hydrobromide in tablets are generally based HPLC with UV detection 2) HPLC with fluorescence detection, 3) capillary zone electrophoretic method 4) densitometric HPTLC, and videodensitometric HPTLC methods. 5) HPLC-electrospray ionization mass spectrometry (HPLC-MS/ESI) 6) and HPLC-positive ion electrospray mass spectrometry method has been reported for the quantification of citalopram in human plasma.7) Officially assay of citalopram hydrobromide is not described in pharmacopoeias. In the present work, an attempt was made to provide a simple, accurate and low cost spectrophotometric method for the quantitative determination of citalopram hydrobromide in pharmaceutical preparations without the interferences of other constituent in the formulations. ExperimentalApparatus A Hitachi U 1100, UV/Vis spectrophotometer (Japan) with silica glass cell of 1 cm thickness was used. Officially calibrated Pyrex glassware was used throughout this study.Reagents and Standards Citalopram hydrobromide was supplied by Bio Fine pharmaceuticals (Pvt.) Ltd. Multan, Pakistan. Commercial dosage forms of citalopram hydrobromide were purchased from a local market. All reagents and solvents used were of Analytical Reagent Grade. 2,3-dichloro-5,6-dicyano-1,4-benzoquinone (DDQ) (Fluka, Switzerland) 2.0 mg ml Ϫ1 solution was prepared in 1,4-dioxan. The standard solutions (1 mg ml Ϫ1) of citalopram hydrobromide were prepared in methanol for method A and citalopram hydrobromide base in chloroform for method B. An aqueous solution of sodium carbonate (0.5 M, Merck, Germany) was prepared in doubly distilled water.Recommended Procedures. Method A Different aliquots of standard solution of citalopram hydrobromide (5-40 mg ml Ϫ1 ) were prepared in methanol. Absorbance of these solutions was noted at 240 nm against a reagent blank.Procedure for the Assay of Citalopram Hydrobromide in Pharmaceutical Formulations Twenty tablets were accurately weighed and powdered. A portion equivalent to 100 mg of citalopram hydrobromide was stirred with 30 ml methanol and the volume was made up to 50 ml in volumetric flask. The solution was filtered with Whatman filter paper No. 1. Then take aliquot of the filtrate made up to 100 ml volume with methanol in volumetric flask. The absorbance was measured at 240 nm against reagent blank.Method B. Preparation of Citalopram Base Solution A citalopram base solution was prepared by transferring 100 ml of 0.5% cital...

A rapid, simple and accurate spectrophotometric method is developed for the determination of ondansetron hydrochloride in pure and tablet formulations. The method depends on the charge-transfer complexation between ondansetron base as n-electron donor with chloranil as p-acceptor to give a colored complex, which absorbs maximally at 470 nm. Beer's law is obeyed in the concentration ranges 70-980 mg mL -1 with molar absorptivity of 4.47´10 2 L mole -1 cm -1 . The proposed method is precise, accurate and specific for the quantitative determination of drug in bulk and tablet formulations.

The comparison of several associated species and plant genome sequencing efforts has increased in recent years. The inflated level of the genomic variety leads to the discovery that the single reference genomes may not reflect the variability in a species, resulting in the evolution of a pan-genome idea. Pan-genomes exhibit a species' genetic variability and contain mutant genes lacking in some individuals and essential genes present in all individuals. Mutant gene classifications often reveal cross-species parallels, including genes for abiotic and biotic stresses generally concentrated within mutant gene groupings. Here we discuss the history of pan-genomics in plants, investigate the causes of gene variation, deletion, and existence and demonstrate why pan-genomes might assist crop genetics and breeding research.

N. Kishore, Proc. Amer. Math. Soc. 14 527 (1963), considered the Rayleigh functions σ n (ν) = ∞ k=1 j −2n νk , n = 1, 2,. . ., where the j νk are the (non-zero) zeros of the Bessel function J ν (z) and has provided a convolution type sum formula for finding σ n in terms of σ 1 ,. .. , σ n−1. Here we investigate corresponding expressions for sums of reciprocal powers of zeros τ n of derivatives and other functions related to Bessel functions. It turns out that we can get results similar to Kishore's expressing τ n in terms of τ 1 ,. .. , τ n−1 and σ 1 ,. .. , σ n .