Thesis (Master)--İzmir Institute of Technology, İzmir, 2004. / Includes bibliographical references (leaves. 70-73).

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A set of water-soluble 4,4-difluoro-4-bora-3a,4a-diaza-s-indacene (BODIPY) derivatives, has been prepared and their spectroscopic properties examined. These dyes can be used as either donor or acceptor in synthesis of through-bond energy transfer cassettes. Sulfonation conditions were developed for several BODIPY dyes to give the mono-sulfonated and di-sulfonated products. Compounds with an aryl iodide could be used for organometallic couplings. Similarly, BODIPYs with an aromatic bromide, but also two chlorine atoms could be replaced via SNAr reactions. The amine sulfonated BODIPY is amenable to couple to biomolecules via acylation reactions. A diazotization/azide reaction sequence was used to convert the amines into azides; the latter may be functionalized via click reactions. Spectral data for these materials indicates they are highly fluorescent probes in aqueous environments. We have also prepared some lipophilic BODIPY derivatives, which can be used for SNAr reactions and make some through-bond, energy transfer cassettes. DichloroBODIPYs can also be used for labeling proteins successfully.

M.Sc. (Chemistry) / An aqueous, simple, environmentally friendly synthetic method for the preparation of water-soluble CuS and CdS semiconductor nanoparticles has been developed. Different capping agents with active functional groups (-COOH, -NH and -OH) namely, alanine, glucuronic acid and thioglycolic acid, have been employed in the preparation copper sulfide (CuS) and cadmium sulfide (CdS) semiconductor nanoparticles as capping molecules. These capping agents were explained in Chapter 3 and 4. The reported nanoparticles display good optical and structural properties. The semiconductor nanoparticles were easily synthesized at low temperatures employing low cost materials. In Chapter 3 colloidal methods were used to develop CuS and CdS nanoparticles from metal acetate as a stabilizing agent at different low temperatures. The effect of temperature on the growth and solubility of nanoparticles was investigated. The absorption spectra of all samples prepared were blue shifted as compared to their bulk materials which signify small particles size. Water-soluble alanine-capped CuS and CdS semiconductor nanoparticles were obtained. The alanine-capped CuS in the form of rods, triangular and spherical like shaped with single crystal phase were successfully attained. Chapter 4 describes the uses of the acids, glucuronic and thioglycolic acids, as capping ligands. The glucuronic acid molecules were found to be the effective ligands to render solubility of the nanoparticles. Solubility tests revealed that both glucuronic acid-capped CuS and CdS nanoparticles were more soluble in water as compared to thioglycolic acid-capped CuS and CdS nanoparticles. In Chapter 5 sulphonated porphyrins were prepared and explored in combining them with nanoparticles. The results obtained from 1H NMR suggest that the porphyrins were sulphonated. The sulphonated porphyrins were conjugated with the water-soluble nanoparticles and this is described in Chapter 6. The results presented in Chapter 6 are in favour of the formation of nanoparticle-porphyrin complexes.

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acase@tulane.edu / In an effort to construct and study aqueous supramolecular assemblies that mimick those of nature (proteins and viral capsids), a novel, water-soluble deep-cavity cavitand has been synthesized – tetra-exo-methyl octa-acid (TEXMOA). In addition, water-soluble cavitand tetra-exo-carboxy tetra-acid (TECTA) was synthesized as an anti-dimerization host to further explore the binding properties of a monomeric host-guest system. The synthetic processes are investigated and discussed in this dissertation. Driven by hydrophobic effect, long-chain alkane guests bind strongly to the pocket of TEMOA in aqueous media. Initial NMR studies suggest that the steric hindrance induced from the exo-methyl groups of TEXMOA is responsible for a non-monotonic assembly profile toward the guests (from monomeric to dimeric and mixture of both in some cases). The synthesis of TECTA required direct ortho metalation and careful purification steps. However, the host still displayed the binding properties as intended, since the carboxylate groups of TECTA in the exo position prevented capsule formation with various aliphatic guests in water. Based on previous findings, modified 1-adamantanoic acids were expected to be potential strong-binding guests for these hosts. Therefore, chloro-, bromo, and iodo-substituted adamantanoic acids were synthesized in order to expand the library of guest molecules. The Z-isomer of these halogenated adamantanoic acids were synthesized from the Z-2-hydroxy-5-adamantanoic acids with the corresponding mineral acids, and these reactions were found to be stereoselective. The amine-footed meta-basket was also synthesized as a potential detection ligand in biosensors via SPR (surface plasmon resonance). The synthesis of the host utilized a modified Staudinger reaction from the azido- precursor. / 1 / Thong Nguyen

Low water solubility of drug compounds limits their dissolution in the aqueous body fluids. When formulated using conventional methods, those poorly water-soluble drugs often results in low and erratic bioavailability. The use of nanoparticle engineering technologies for the formulation of poorly water-soluble drugs is a valuable strategy to enhance dissolution rates and thus bioavailability. In Chapter 2, a nanoparticle engineering process, Evaporative Precipitation into Aqueous Solution (EPAS), was modified to provide improved control over the size of precipitated particles. The improved process, Advanced EPAS, was employed to prepare nanoparticles of the poorly water-soluble drug itraconazole (ITZ). The influence of processing parameters and formulation aspects on the size of suspended ITZ-particles was investigated. The process was shown to be robust such that the size distribution of dispersed nanoparticles was largely independent across the different parameters. In Chapter 3, aqueous nanoparticulate dispersions of the poorly soluble drug mefenamic acid (MFA) were developed and subsequently incorporated into controlled release formulations employing spray-drying. Release of MFA from spray-dried formulations was sustained and complete demonstrating the feasibility of using nanoparticulates for the preparation of controlled release systems. In Chapter 4, the nanoparticle engineering process, Rapid Freezing (RF), was utilized to produce nanostructured, amorphous aggregates of the poorly water soluble drug ketoprofen (RF-KET). The stability of RF-KET against recrystallization was improved through the deposition of a hydrophobic plasma-polymerized film. The coating presented an effective barrier against surface mobility and moisture uptake resulting in enhanced stability of RF-KET for up to six months at accelerated storage conditions as compared to three days for uncoated RF-KET. / text