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Journal of Thermal Analysis and Calorimetry
Authors: Susan Moreno-Molek, Salaam Saleh, Druthiman Reddy Mantheni, Manik Pavan Kumar Maheswaram, Tobili Sam-Yellowe, and Alan T. Riga

cytokine receptors using the Protein Information Resources search window ( http://pir.georgetown.edu/cgi-bin/comp_mw.pl ). Dielectric thermal analysis A TAI 2970 DEA was used to measure the electrical conductivity of

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such as dielectric thermal analysis (DETA) and thermogravimetry (TG), as the basis for diagnostic test fabrication. DETA is a thermoanalytical technique that measures changes in electrical properties of a sample, liquid or solid, as a function

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Journal of Thermal Analysis and Calorimetry
Authors: Dhruthiman R. Mantheni, M. P. K. Maheswaram, Hany F. Sobhi, Naullage Indika Perera, Alan T. Riga, M. Ellen Matthews, and K. Alexander

in the crystal lattice[ 10 ]. Dielectric thermal analysis of amino acids also exhibited an enhanced electrical linear conductivity increase prior to the melt. Matthews and Riga [ 10 ] referred to these new properties as dielectric viscoelastic

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Abstract  

Dielectric Thermal Analysis (DETA) of drugs, proteins and amino acids reveals a strongly linear conductivity increase prior to and peaking at the melt, associated with dielectric viscoelastic properties of the material. Premelt onset and peak are shown to depend on thermal history. Comparisons of neat amino acid samples to samples heated to 150 °C; dried in a desiccator; or heated above their melting point and cooled show significant premelt and melt shifts. Melts are also correlated with phase transitions observed by Differential Scanning Calorimetry (DSC). Activation energies attributed to charging in the premelt for amino acids were typically 250 J/mole.

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Abstract  

The long-term goal of this investigation is to study the effects of increased cholesterol levels on the molecular activity of membrane-bound enzymes such as nitric oxide synthase, that are critical in the functioning of the cardiovascular system. In this particular investigation, we used differential scanning calorimetry (DSC) and dielectric thermal analysis (DETA) to study the effect of added cholesterol on melting/recrystallization and dielectric behavior, respectively, of phosphatidylcholine (PC) bilayered thin films. We also used electrochemical methods to investigate the effect of added cholesterol on the redox behavior of the oxygenase domain of nitric oxide synthase as a probe embedded in the PC films. The results show that added cholesterol in the PC films seems to depress the molecular dynamics as indicated by lowered current responses in the presence of cholesterol as well as a slight increase of the transition temperature in the overall two-phase regime behavior observed in PC–cholesterol films. These results are rationalized in the context of the general DSC and DETA behaviors of the PC–chol films.

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Solid-state mechanical properties of crystalline drugs and excipients

New data substantiate discovered dielectric viscoelastic characteristics

Journal of Thermal Analysis and Calorimetry
Authors: Shravan Singh Thakur, Manik Pavan Kumar Maheswaram, Dhruthiman Reddy Mantheni, Lakshmi Kaza, Indika Perara, David W. Ball, John Moran, and Alan T. Riga

signature patterns of human cytokine and soluble cytokine receptors investigated using dielectric thermal analysis and thermogravimetry . J Therm Anal Calorim Anal . 2011 . 10.1007/s10973-011-1530-9 . 18

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