Binary and Ternary Complexes of Arteether β-CD - Characterization, Molecular Modeling and in Vivo Studies

The purpose of the present work is to improve the antimalarial activity of arteether through enhancing its solubility subsequently bioavailability by incorporating the drug into the cyclodextrins cavity. The effect of hydrophilic polyvinyl propylene (PVP) polymer on the complexation and solubilizing efficiencies of cyclodextrins (CDs) is also elucidated. Inclusion of arteether molecule in solid state was evidenced by Differential scanning calorimeter (DSC), Powder X-ray diffractometery (PXRD), and in solution state by NMR and solution calorimetry. A 1:1 stoichiometry was proposed by the phase solubility studies both in presence and absence of PVP. The most plausibe mode of inclusion of arteether into the CD cavity is revealed by molecular modeling studies utalizing Fast Rigid Exhaustive Docking acronym. Solution calorimetry was used further to confirm 1:1 stiochiometry in presence or absence of PVP by determining the enthalpy of interaction between the drug and cyclodextrins. The inclusion of drug was found to be exothermic process accompanied by small positive value of entropy (ΔSo). The methylated-β-CD showed the best ability to solublize arteether which is approximately at par with β-CD in the presence of PVP. Better complexation efficiency of β-CD in presence of PVP is also reflected by the higher numerical values of stability constant (K). Compelete eradication of the parasite from the blood and highest anti-malarial pharmacological activity was observed in the complexes of arteether with M-?-CD while 83.7% was observed for ternary complexes of β-CD in presence of PVP.

Review of Linear Switched Reluctance Motor Designs for Linear Propulsion Applications

Linear switched reluctance motor(LSRM)and its applications in different industries have been an interesting research topic for the past few years.LSRMs have proved to be a suitable alternative in a variety of applications requiring linear motion.However,its use is not that popular which instigated an active interest in the evolution of newer LSRM configurations.Enhancement in its propulsion force along with the reduction in force ripples,weight,acoustic noise,and vibration have been the main objectives in recently proposed LSRM designs.In this paper,recently proposed LSRM designs are reviewed and analyzed.The paper presents a one-stop introduction and a complete update to the designs,both in terms of qualitative and quantitative parameters.In addition,it takes into account the challenges in the implementation of these designs.Based on a detailed comparison of these designs as presented in this paper,an appropriate design can be chosen for a given application.

Crystal habit,characterization and pharmacological activity of various crystal forms of arteether

The aim of this study was to investigate and characterize different crystal forms of arteether,a rapidly acting,highly potent antimalarial drug for the treatment of acute Plasmodium falciparum malaria.Six different crystal forms were prepared utilizing various polar and non-polar solvents.Scanning electron microscopy(SEM)revealed differences in the surface characteristics of the six forms from those of a commercial sample.Differential scanning calorimetry(DSC)revealed the absence of a desolvation endotherm indicating that the forms were neither hydrates nor solvates.Powder X-ray diffraction(PXRD)patterns of the forms showed much weaker major peaks than in the commercial sample indicating them to be less crystalline.Solubility and dissolution studies showed that the most amorphous form was the most soluble and possessed the highest antimalarial activity.