89 research outputs found
UV-Visible Spectrophotometric Method Development and Validation of Itraconazole in Bulk and Capsule Formulation
A simple, rapid, accurate and precise UV method was developed and validated for the estimation of Itraconazole in pharmaceutical dosage form. Spectroscopic method was carried out by using acidic ethanol as solvent. Itraconazole detection wavelength was set at 262nm for validation purpose linearity, accuracy, repeatability, precision, LOD, LOQ, and ruggedness parameters were studied. The linearity was found to be in the range of 2-12 g/ml
Synthesis, Characterization and Study of Microbiological Activity of Some Transition Metal Ion Complexes with [N -(o -hydroxy benzylidene) Pyridine -2 -Amine] (NOHBPA)
ABSTRACT A Schiff base ligand derived from o -hydroxy benzaldehyde and 2 -amino pyridine and its transition metal complexes with Fe(II), Cu(II), Ru(III) and Rh(III) have been synthesized which were characterized by elemental analysis, molar conductance, magnetic susceptibility, electronic spectra, IR and ESR spectroscopy. The metal complexes are coloured, solid and non -hygroscopic in nature. The Schiff base ligand exhibits tridentate nature, coordination through azomethine nitrogen, phenolic oxygen and nitrogen of pyridine ring to the metal ions. On the basis of electronic spectral analysis and magnetic susceptibility values, geometry of complexes were proposed to be octahedral. The molar conductivity data of complexes suggests their non -electrolytic nature. The ligand and metal complexes have been screened for their microbiological activity
Discovery of Ranking Fraud for Mobile Apps Evidence Aggregation Based Ranking Fraud Detection (EA-RFD)
Ranking fraud within the mobile App market refers to dishonest or deceptive activities that have a purpose of bumping up the Apps within the quality list. Indeed, it becomes additional and additional frequent for App developers to use shady suggests that, like inflating their Apps? sales or posting phony App ratings, to commit ranking fraud. Whereas the importance of preventing ranking fraud has been well known, there's restricted understanding and analysis during this space. to the present finish, during this paper, we offer a holistic read of ranking fraud and propose a ranking fraud detection system for mobile Apps. Specifically, we tend to 1st propose to accurately find the ranking fraud by mining the active periods, specifically leading sessions, of mobile Apps. Such leading sessions will be leveraged for detective work the native anomaly rather than world anomaly of App rankings. Moreover, we tend to investigate 3 forms of evidences, i.e., ranking based mostly evidences, rating {based based mostly primarily based mostly} evidences and review based evidences, by modeling Apps? ranking, rating and review behaviors through applied mathematics hypotheses tests. Additionally, we tend to propose AN optimization based mostly aggregation methodology to integrate all the evidences for fraud detection. Finally, we tend to evaluate the projected system with real-world App knowledge collected from the iOS App Store for an extended fundamental measure. Within the experiments, we tend to validate the effectiveness of the projected system, and show the quantifiability of the detection algorithmic program furthermore as some regularity of ranking fraud activities
Mechanical Properties of Glassy Polyethylene Nanofibers via Molecular Dynamics Simulations
The extent to which the intrinsic mechanical properties of polymer fibers depend on physical size has been a matter of dispute that is relevant to most nanofiber applications. Here, we report the elastic and plastic properties determined from molecular dynamics simulations of amorphous, glassy polymer nanofibers with diameter ranging from 3.7 to 17.7 nm. We find that, for a given temperature, the Youngâs elastic modulus E decreases with fiber radius and can be as much as 52% lower than that of the corresponding bulk material. Poissonâs ratio Îœ of the polymer comprising these nanofibers was found to decrease from a value of 0.3 to 0.1 with decreasing fiber radius. Our findings also indicate that a small but finite stress exists on the simulated nanofibers prior to elongation, attributable to surface tension. When strained uniaxially up to a tensile strain of Δ = 0.2 over the range of strain rates and temperatures considered, the nanofibers exhibit a yield stress Ïy between 40 and 72 MPa, which is not strongly dependent on fiber radius; this yield stress is approximately half that of the same polyethylene simulated in the amorphous bulk.DuPont MIT AllianceDuPont (Firm) (Young Professor Award
A Dual FluorescenceâSpin Label Probe for Visualization and Quantification of Target Molecules in Tissue by Multiplexed FLIMâEPR Spectroscopy
Simultaneous visualization and concentration quantification of molecules in biological tissue is an important though challenging goal. The advantages of fluorescence lifetime imaging microscopy (FLIM) for visualization, and electron paramagnetic resonance (EPR) spectroscopy for quantification are complementary. Their combination in a multiplexed approach promises a successful but ambitious strategy because of spin label-mediated fluorescence quenching. Here, we solved this problem and present the molecular design of a dual label (DL) compound comprising a highly fluorescent dye together with an EPR spin probe, which also renders the fluorescence lifetime to be concentration sensitive. The DL can easily be coupled to the biomolecule of choice, enabling inâ
vivo and inâ
vitro applications. This novel approach paves the way for elegant studies ranging from fundamental biological investigations to preclinical drug research, as shown in proof-of-principle penetration experiments in human skin exâ
vivo
Synthetic Nanoparticles for Vaccines and Immunotherapy
The immune system plays a critical role in our health. No other component of human physiology plays a decisive role in as diverse an array of maladies, from deadly diseases with which we are all familiar to equally terrible esoteric conditions: HIV, malaria, pneumococcal and influenza infections; cancer; atherosclerosis; autoimmune diseases such
as lupus, diabetes, and multiple sclerosis. The importance of understanding the function of the immune system and learning how to modulate immunity to protect against or treat disease thus cannot be overstated. Fortunately, we are entering an exciting era where the
science of immunology is defining pathways for the rational manipulation of the immune system at the cellular and molecular level, and this understanding is leading to dramatic advances in the clinic that are transforming the future of medicine.1,2 These initial advances are being made primarily through biologic drugsâ recombinant proteins (especially antibodies) or patient-derived cell therapiesâ but exciting data from preclinical studies suggest that a marriage of approaches based in biotechnology with the materials science and chemistry of nanomaterials, especially nanoparticles, could enable more effective and safer immune engineering strategies. This review will examine these nanoparticle-based strategies to immune modulation in detail, and discuss the promise and outstanding challenges facing the field of immune engineering from a chemical biology/materials engineering perspectiveNational Institutes of Health (U.S.) (Grants AI111860, CA174795, CA172164, AI091693, and AI095109)United States. Department of Defense (W911NF-13-D-0001 and Awards W911NF-07-D-0004
Aqueous two-phase extraction in combination with ultrafiltration for downstream processing of Ipomoea peroxidase
The partition behaviour of a plant peroxidase extracted from the leaves of Ipomoea palmetta was studied in aqueous two-phase systems. The influence of various parameters such as system pH, phase composition, phase polymer molecular weight and concentration of neutral salt on differential partitioning of the enzyme and cell debris into opposite phases were evaluated. Desirable conditions for differential partitioning were found in systems having polyethylene glycol of lower molecular weight 1550, where the enzyme partitioned to the bottom phase and the cell debris partitioned to the top phase. Optimum conditions for extraction of the enzyme were observed in a polyethylene glycol (PEG-1550)/KH2PO4 system having 2% NaCl. Hence, using this system, extraction, enrichment and purification of the enzyme was performed on a larger-scale (1-l scale) in combination with ultrafiltration to obtain about 76% recovery, 5.9-fold purity and 9.7-fold activity concentration of the enzyme
Drop formation in aqueous two-phase systems
Extraction using aqueous two-phase systems (ATPSs) is a versatile technique for the downstream processing of various proteins/enzymes. The study of drop formation deals with the fundamental understanding of the behavior of liquid drops under the influence of various external body as well as surface forces. These studies provide a basis for designing of the extractions in column contactors in which liquid drops play a major role. Most of the drop formation studies reported so far is restricted to aqueousâorganic systems. ATPSs, differ from aqueousâorganic systems in their physical properties. In view of this, an attempt was made to develop a model for drop formation in ATPSs adopting the information available on aqueousâorganic systems. In order to validate the model, experiments were performed by using polyethylene glycol (PEG)/salt systems of different phase compositions at various flow rates. At low flow rates the single stage model and at high flow rates the two stage model are able to predict the drop volume during its formation from tip of capillary. The experimental results were found to agree reasonably well with those predicted by the model
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