DEVELOPMENT AND VALIDATION STABILITY INDICATING HPTLC METHOD FOR DETERMINATION OF VILDAGLIPTIN AND METFORMIN HYDROCHLORIDE IN THE PHARMACEUTICAL DOSAGE FORMS

Objective: A simple, precise, and accurate stability indicating high-performance thin layer chromatography method was developed and validated of vildagliptin (VIL) and metformin (MET) in pharmaceutical dosage forms.Methods: In the present study, system suitability test, stress study, alkali hydrolysis, acid hydrolysis, neutral hydrolysis, oxidative stress degradation, dry heat degradation, wet heat degradation, photodegradation study has been used. In this method, optimization by changing various parameters, such as organic solvent and the composition of the mobile phase, acid or base modifier used in the mobile phase; by varying one parameter and keeping all other conditions constant. 10 µl of the stock solution for MET (500 ng/band) and 2 µl of the stock solution for VIL (100 ng/band) were applied to TLC plates. The final solutions were applied on the HPTLC plates and these were developed as per the optimized densitometry conditions.Results: From the spectra, it was observed that MET and VIL exhibited good absorbance at about 217 nm. Both the drugs showed degradation with additional peaks at Rfvalues of 0.16 for MET and with Rfvalues 0.81 for VIL respectively. The method was validated for linearity, precision, accuracy, limit of detection, limit of quantification, ruggedness, specificity, and robustness. Good separation was achieved by using the mobile phase Hexane: Methanol: Acetonitrile: Glacial Acetic Acid (2:3.5:2.5:0.2 v/v/v/v) with retardation factor (Rf) values of 0.22±0.01 for MET and 0.73±0.02 for VIL.Conclusion: A validated HPTLC method was developed for the determination of metformin hydrochloride and vildagliptin. The method is simple, quick, and can be applied routinely for the analysis of these drugs from marketed dosage forms

In vitro antimitotic activity and in silico study of some 6-fluoro-triazolo-benzothiazole analogues

In this work, nine 6-fluoro-triazolo-benzothiazole derivatives were prepared and evaluated for in vitro antimitotic activity. In addition, in silico study was also done using tubulin protein (PDB: 6QQN) by molecular docking method. Results revealed that TZ2 and TZ9 were the most active compounds with antimitotic action opposing the standard drug, aspirin. Results of molecular docking exhibited the inhibitory potential of triazolo-benzothiazole against tubulin protein. The mitotic study indicates the efficacy of triazolo-benzothiazole analogues in inhibiting the proliferation of cancer cells either by promoting microtubule formation or affecting microtubules, thereby preventing microtubule breakdown

On representation of electron-electron repulsion energies by simple one-electron functionals

An analysis is presented of the various functional forms representating coulomb energies and the electron-electron repulsion energy in atomic and molecular systems. (AIP

Rigorous relationships among quantum-mechanical kinetic energy and atomic information entropies: upper and lower bounds

An uncertainty-type lower bound [I. Bialynicki-Birula and J. Mycielski, Commun. Math. Phys. 44, 129 (1975)] to the information-entropy sum in complementary spaces has recently been reformulated by Gadre et al. [Phys. Rev. A 32, 2602 (1985)] in terms of the respective one-particle probability densities. This bound has been exploited to derive rigorous upper as well as lower bounds to the information entropies and their sum in terms of the corresponding second moments of their distributions. Thus the present work establishes a direct connection, as suggested by Sears, Parr, and Dinur [Israel J. Chem. 19, 165 (1980)], between the quantum-mechanical kinetic energy and information entropy in position space. It has also been demonstrated that given at least one arbitrary moment-type constraint in each space, it is possible to derive an upper bound to the information entropy sum in complementary spaces

On the similarity between molecular electron densities, electrostatic potentials and bare nuclear potentials

The similarities among the molecular contours of three scalar fields, viz. electron density (ED), electrostatic potential (ESP) and bare nuclear potential (BNP) have been investigated. The topological resemblance between ESP and ED contour diagrams (as prompted by the Thomas-Fermi model) is more pronounced than that for BNP and ED contour diagrams (as predicted by the local density functional model of Parr, Gadre and Bartolotti) with three-membered ring systems as test cases. An analysis of critical points of these distributions has also been included. Thus it may be conjectured that ED maps may prove useful in predicting reactive sites in molecules

Chronic tendoachilles rupture

We report two cases of chronic tendoachilles (TA) rupture, which was treated with V-Y plasty and turned down flap from the proximal segment to cover the defect. Chronic TA ruptures can be challenging to treat. A number of operations have been described for the repair and augmentation of the chronic TA rupture

Analysis of atomic electron momentum densities: use of information entropies in coordinate and momentum space

The entropy maximization procedure has been extended to treat simultaneously the densities in coordinate and momentum space. The key quantity to be maximized is the sum of information entropies in complementary spaces rather than the entropy in one space alone. This modified procedure has been used to assess the quality of refined electron momentum densities for He, Be and H2. The momentum density which maximizes the entropy sum yields good estimates of Compton lineshape and related momentum space expectation values

Some novel characteristics of atomic information entropies

Near-Hartree-Fock information entropies Sρ=-Fρ(r)lnρ(r)dr and Sγ=-Fγ (ρ)lnρ(ρ)dρ, where ρ(r) and ρ(ρ) are one-electron densities in coordinate and momentum space, respectively, have been computed for atoms in their ground and excited states. The information entropies for the harmonic oscillator and hydrogen atom as prototype systems are also discussed. The result of this exercise is a numerical discovery that for the ground state, Sρ+Sγ shows its minimum value. This study for atoms in their ground states, using wave functions of single-zeta, double-zeta, and near-Hartree-Fock quality, also unearths a startling feature that the entropy sum, Sρ+Sγ , increases with an enhancement in the ground-state wave-function quality

Iris Recognition using Consistent Corner Optical Flow

Abstract. This paper proposes an efficient iris based authentication system. Iris segmentation is done using an improved circular hough transform and robust integro-differential operator to detect inner and outer iris boundary respectively. The segmented iris is normalized to polar coordinates and preprocessed using LGBP (Local Gradient Binary Pattern). The corners features are extracted and matched using dissimilarit