Physical Sciences and Mathematics Commons^™

Anti-Solvent Precipitation And Subsequent Film Formation Of Hydrophobic Drugs For Drug Delivery, Xiangxin Meng

Dissertations

It is estimated that about forty percent of the drug molecules being developed by the pharmaceutical industry are hydrophobic in nature, leading to poor water solubility and bioavailability in the gastrointestinal tract. Dissolution is a limiting factor in their in vivo performance, and increasing their dissolution rate is a major challenge. It has been proven that the dissolution rate is directly proportional to the specific surface area, which can be effectively increased by reducing the particle size. Therefore, considerable efforts have gone into developing reliable and efficient methods for the manufacture of fine particles. Particle size reduction technologies such as …

Application Of Raman Spectroscopy In Pharmaceuticals, Anna Zarow

Dissertations

Experimental research on the use of Raman spectroscopy as an in- and on-line sensing tool and a complementary characterization technique for pharmaceutical applications is presented in this thesis. In the first chapter following a broad overview, the use of Raman spectroscopy, together with x-ray powder diffraction, scanning electron microscopy (SEM) and differential scanning calorimetry, for multilevel characterization of cryomilled powders, and the melt-grown amorphous phase of griseofulvin, a model active pharmaceutical ingredient (API), is presented and discussed in detail. A key feature was the observation of a broad inelastic background superimposed on the Raman spectra of cryomilled powders, which is …

Synthesis Towards Synthetic Adenosine Receptor, Rajni Gupta

Theses

Adenosine is a biologically important molecule as it acts as local modulator with cytoprotective function in the body. Adenosine accumulates in the extracellular space in response to metabolic stress and cell damage, and elevations in extracellular adenosine level are found in conditions like myocardial ischemia, hypoxia, inflammation and trauma. Its abnormal concentration therefore could be a marker of many diseases. Therefore determining its concentration can help understand the physiological state of the body. However its selective detection by synthetic receptors is not possible till date.

Efforts have been made here to design molecular tweezer for adenosine. Multistep synthesis was done …

Thermochemistry And Bond Energies Of Acetohydrazide, Amides And Cyclic Alkyl Ethers, Sumit Charaya

Theses

Structure, thermochemical properties, bond energies and internal rotation potentials of Acetic Acid Hydrazide (CH₃CONHNH₂), Acetamide (CH₃CONH₂) and N-methyl Acetamide (CH3CONHCH3) and their radicals corresponding to loss of hydrogen atom have been studied. Gas phase standard enthalpies of formation and bond energies were calculated using the DFT methods B3LYP/6-31G(d,p), B3LYP/6-31G(2d,2p) and the composite CBS-QB3 methods employing a series of work reactions to further improve accuracy of the ΔH_f°(298K). Molecular structures, vibration frequencies and internal rotor potentials were calculated at DFT level. The enthalpies of the parent molecules CH₃-C=ONHNH_{2 …}