FORCE DEGRADATION STUDY AND RP-HPLC METHOD DEVELOPMENT FOR ESTIMATION OF FLUVOXAMINE MALEATE IN TABLET

Objective: To evaluate stability of drug by force degradation studies and to develop validated RP-HPLC method for quantitative estimation of fluvoxamine maleate in pharmaceutical dosage form.Methods: The optimized chromatographic conditions utilizes reversed-phase C18 Hyperchrome ODS column (250X4.6 mm, 5µ), mobile phase comprised of Methanol and Phosphate buffer (pH-2.5) in the ratio of 70:30 v/v, flow rate of 1 ml/min at ambient temperature and UV detection at 250 nm. Results: In the proposed method the retention time of fluvoxamine was found to be 5.94 min. The linearity of the proposed method was tested in the range of 10-50 μg/ml and correlation coefficient was found to be 0.998. The accuracy of the proposed method was carried out by standard addition method and found to be 99.62%. The % RSD of precision study was calculated as 0.69. The standard and marketed formulation exposed to hydrolytic and oxidative stress conditions indicates significant degradation with good resolution between the peaks corresponds to degradation products and analyte. The proposed force degradation study shows that fluvoxamine is labile molecule to acid, alkali, neutral and oxidative conditions and also susceptible to degradation when exposed to UV light, and humidity conditions while it was stable under dry heat (50 °C).Conclusion: The proposed validated HPLC method for the quantitative estimation of fluvoxamine maleate in tablet dosage form is accurate, precise, economic, and robust. The developed stability indicating method can be recommended for analysis of drug and its degradation products in stability samples.Â

Spatially resolved simulation of a radio frequency driven micro atmospheric pressure plasma jet and its effluent

Radio frequency driven plasma jets are frequently employed as efficient plasma sources for surface modification and other processes at atmospheric pressure. The radio-frequency driven micro atmospheric pressure plasma jet ($\mu$APPJ) is a particular variant of that concept whose geometry allows direct optical access. In this work, the characteristics of the $\mu$APPJ operated with a helium-oxygen mixture and its interaction with a helium environment are studied by numerical simulation. The density and temperature of the electrons, as well as the concentration of all reactive species are studied both in the jet itself and in its effluent. It is found that the effluent is essentially free of charge carriers but contains a substantial amount of activated oxygen (O, O$_3$ and O$_2(^1\Delta)$). The simulation results are verified by comparison with experimental data

Simulations of electromagnetic effects in high frequency capacitively coupled discharges using the Darwin approximation

The Darwin approximation is investigated for its possible use in simulation of electromagnetic effects in large size, high frequency capacitively coupled discharges. The approximation is utilized within the framework of two different fluid models which are applied to typical cases showing pronounced standing wave and skin effects. With the first model it is demonstrated that Darwin approximation is valid for treatment of such effects in the range of parameters under consideration. The second approach, a reduced nonlinear Darwin approximation-based model, shows that the electromagnetic phenomena persist in a more realistic setting. The Darwin approximation offers a simple and efficient way of carrying out electromagnetic simulations as it removes the Courant condition plaguing explicit electromagnetic algorithms and can be implemented as a straightforward modification of electrostatic algorithms. The algorithm described here avoids iterative schemes needed for the divergence cleaning and represents a fast and efficient solver, which can be used in fluid and kinetic models for self-consistent description of technical plasmas exhibiting certain electromagnetic activity

Entire functions with Julia sets of positive measure

Let f be a transcendental entire function for which the set of critical and asymptotic values is bounded. The Denjoy-Carleman-Ahlfors theorem implies that if the set of all z for which |f(z)|>R has N components for some R>0, then the order of f is at least N/2. More precisely, we have log log M(r,f) > (N/2) log r - O(1), where M(r,f) denotes the maximum modulus of f. We show that if f does not grow much faster than this, then the escaping set and the Julia set of f have positive Lebesgue measure. However, as soon as the order of f exceeds N/2, this need not be true. The proof requires a sharpened form of an estimate of Tsuji related to the Denjoy-Carleman-Ahlfors theorem.Comment: 17 page

Systematic assessment of the growth plates of the wrist in young gymnasts: Development and validation of the Amsterdam MRI assessment of the Physis (AMPHYS) protocol

Objectives To develop and validate a protocol for MRI assessment of the distal radial and ulnar periphyseal area in gymnasts and non-gymnasts. Methods Twenty-four gymnasts with wrist pain, 18 asymptomatic gymnasts and 24 non-gymnastic controls (33 girls) underwent MRI of the wrist on a 3T scanner. Sequences included coronal proton density-weighted images with and without fat saturation, and three-dimensional water-selective cartilage scan and T2 Dixon series. Skeletal age was determined using hand radiographs. Three experienced musculoskeletal radiologists established a checklist of possible (peri)physeal abnormalities based on literature an