Solid dispersion: A promising technique to enhance solubility of poorly water soluble drug

Poorly water soluble compounds have solubility and dissolution related bioavailability problems. The present review deals in detail about solid dispersion technology and its manufacturing techniques at laboratory and industrial level. This highlight about various hydrophilic polymers used in this technique to enhance solubility of poorly soluble drugs. It also discusses about modern characterization technique to characterize solid dispersion. In this review, it is intended to discuss the recent advances related on the area of solid dispersion technology.Keywords: Solid dispersion; Carriers; Solubility; Dissolution; Bioavailability

Solid dispersion: A promising technique to enhance solubility of poorly water soluble drug

Poorly water soluble compounds have solubility and dissolution related bioavailability problems. The present review deals in detail about solid dispersion technology and its manufacturing techniques at laboratory and industrial level. This highlight about various hydrophilic polymers used in this technique to enhance solubility of poorly soluble drugs. It also discusses about modern characterization technique to characterize solid dispersion. In this review, it is intended to discuss the recent advances related on the area of solid dispersion technology.Keywords: Solid dispersion; Carriers; Solubility; Dissolution; Bioavailability

Duality in the Quantum Hall Effect - the Role of Electron Spin

At low temperatures the phase diagram for the quantum Hall effect has a powerful symmetry arising from the Law of Corresponding States. This symmetry gives rise to an infinite order discrete group which is a generalisation of Kramers-Wannier duality for the two dimensional Ising model. The duality group, which is a subgroup of the modular group, is analysed and it is argued that there is a quantitative difference between a situation in which the spin splitting of electron energy levels is comparable to the cyclotron energy and one in which the spin splitting is much less than the cyclotron energy. In the former case the group of symmetries is larger than in the latter case. These duality symmetries are used to constrain the scaling functions of the theory and, under an assumption of complex meromorphicity, a unique functional form is obtained for the crossover of the conductivities between Hall states as a function of the external magnetic field. This analytic form is shown to give good agreement with experimental data. The analysis requires a consideration of the way in which longitudinal resistivities are extracted from the experimentally measured longitudinal resistances and a novel method is proposed for determining the correct normalisation for the former.Comment: 22 pages, 8 figures, typeset in LaTe

Standard Model Higgs boson mass from inflation: two loop analysis

We extend the analysis of \cite{Bezrukov:2008ej} of the Standard Model Higgs inflation accounting for two-loop radiative corrections to the effective potential. As was expected, higher loop effects result in some modification of the interval for allowed Higgs masses m_min<m_H<m_max, which somewhat exceeds the region in which the Standard Model can be considered as a viable effective field theory all the way up to the Planck scale. The dependence of the index n_s of scalar perturbations on the Higgs mass is computed in two different renormalization procedures, associated with the Einstein (I) and Jordan (II) frames. In the procedure I the predictions of the spectral index of scalar fluctuations and of the tensor-to-scalar ratio practically do not depend on the Higgs mass within the admitted region and are equal to n_s=0.97 and r=0.0034 respectively. In the procedure II the index n_s acquires the visible dependence on the Higgs mass and and goes out of the admitted interval at m_H below m_min. We compare our findings with the results of \cite{DeSimone:2008ei}.Comment: 24 paged, 9 figures. Journal version (typos fixed, expanded discussions

Development and validation of novel HPLC method for the estimation of Rutin in crude hydromethanolic leaf extract of Prosopis cineraria

A simple, specific, accurate and precise high performance liquid chromatography method has developed for the estimation of rutin in Prosopis cineraria. The chromatographic separation was achieved by using C18 column, 150 x 4.6mm i.d., 5µ bonded phase octadecylsilane (Thermo Labs Hypersil). Mobile phase was composed of 80 parts of methanol &amp; 20 parts of 0.05% formic acid. The pH of the mobile phase was 3.2.The retention time of rutin was found 5.7 min with 1 mL/min flow rate at ambient temperature. The estimation was performed on PDA detector at 281 nm. In this study, an excellent linearity was obtained with r2 0.999. Besides, the chromatographic peak was found sharp &amp; symmetric. The proposed method was validated in terms of the analytical parameters such as accuracy, linearity, precision, robustness, limit of detection (LOD), limit of quantification (LOQ) were determined based on the International Conference on Harmonization (ICH) guidelines. The detector response was linear in the range of 2-10 µg/mL. The proposed method was successfully applied for the estimation of the constituents in crude extract of Prosopis cineraria. This study established a quantitative method for the determination of rutin from Prosopis cineraria. &nbsp;Keywords: Prosopis cineraria, HPLC, Validation, Rutin

Comparative fingerprint and extraction yield of Prosopis cineraria (Lin.) Druce. Leaves with phenolic compounds (Gallic acid) & flavonoids (Rutin)

The main objective of this study is to analyse the extraction yield of Prosopis cineraria leaf with respect to phenolic compounds (Gallic acid) and flavonoids (Rutin). UV and FTIR spectroscopic methods were employed for qualitative and quantitative analysis of phenolic compounds (gallic acid) and flavonoids (rutin) in the leaf extract of Prosopis cineraria. The extraction yield of methanolic extract was found to be superior. The FTIR signals at 675-600, 1225–950, 1540-1870, and 3500–3200 cm-1, are the indicator of presence of phenol (Gallic acid) &amp; Rutin (flavonoid). &nbsp;These signals were used to identify the presence of the functional groups in the extract. This study concludes that data obtained from the UV &amp; FTIR spectroscopy is enough to fingerprint &amp; evaluate extraction yield of Prosopis cineraria. Key words:&nbsp; UV spectroscopy, FTIR spectroscopy, Methanolic extract, Rutin, Gallic acid, Prosopis cineraria

Universal flow diagram for the magnetoconductance in disordered GaAs layers

The temperature driven flow lines of the diagonal and Hall magnetoconductance data (G_{xx},G_{xy}) are studied in heavily Si-doped, disordered GaAs layers with different thicknesses. The flow lines are quantitatively well described by a recent universal scaling theory developed for the case of duality symmetry. The separatrix G_{xy}=1 (in units e^2/h) separates an insulating state from a spin-degenerate quantum Hall effect (QHE) state. The merging into the insulator or the QHE state at low temperatures happens along a semicircle separatrix G_{xx}^2+(G_{xy}-1)^2=1 which is divided by an unstable fixed point at (G_{xx},G_{xy})=(1,1).Comment: 10 pages, 5 figures, submitted to Phys. Rev. Let

Calculating the jet-quenching parameter in STU background

In this paper we use the AdS/CFT correspondence to compute the jet-quenching parameter in a N=2 thermal plasma. We consider the general three-charge black hole and discuss some special cases. We add a constant electric field to the background and find the effect of the electric field on the jet-quenching parameter. Also we include higher derivative terms and obtain the first-order correction for the jet-quenching parameter.Comment: 17 pages, 3 figures, revised versio

STU/QCD Correspondence

In this review article we consider a special case of $D=5$, $\mathcal{N}=2$ supergravity called the STU model. We apply the gauge/gravity correspondence to the STU model to gain insight into properties of the quark-gluon plasma. Given that the quark-gluon plasma is in reality described by QCD, therefore we call our study STU/QCD correspondence. First, we investigate the thermodynamics and hydrodynamics of the STU background. Then we use dual picture of the theory, which is type IIB string theory, to obtain the drag force and jet-quenching parameter of an external probe quark.Comment: 56 pages, 20 figures. The paper is review of previous papers arXiv:0905.1466, arXiv:1005.1368, arXiv:1011.2291 and arXiv:1011.2291. Published versio

Hamiltonian theory of gaps, masses and polarization in quantum Hall states: full disclosure

I furnish details of the hamiltonian theory of the FQHE developed with Murthy for the infrared, which I subsequently extended to all distances and apply it to Jain fractions \nu = p/(2ps + 1). The explicit operator description in terms of the CF allows one to answer quantitative and qualitative issues, some of which cannot even be posed otherwise. I compute activation gaps for several potentials, exhibit their particle hole symmetry, the profiles of charge density in states with a quasiparticles or hole, (all in closed form) and compare to results from trial wavefunctions and exact diagonalization. The Hartree-Fock approximation is used since much of the nonperturbative physics is built in at tree level. I compare the gaps to experiment and comment on the rough equality of normalized masses near half and quarter filling. I compute the critical fields at which the Hall system will jump from one quantized value of polarization to another, and the polarization and relaxation rates for half filling as a function of temperature and propose a Korringa like law. After providing some plausibility arguments, I explore the possibility of describing several magnetic phenomena in dirty systems with an effective potential, by extracting a free parameter describing the potential from one data point and then using it to predict all the others from that sample. This works to the accuracy typical of this theory (10 -20 percent). I explain why the CF behaves like free particle in some magnetic experiments when it is not, what exactly the CF is made of, what one means by its dipole moment, and how the comparison of theory to experiment must be modified to fit the peculiarities of the quantized Hall problem