Metastable State Photoacids and Ultrasound Responsive Carbon Monoxide Releasing Polymer Micelle
Alghazwat, Osamah Zaid Saleh
MetadataShow full item record
This dissertation described my Ph.D. work on the development of a novel metastable state photoacids (mPAH), which can be activated by near infrared light and a reversible mPAH switched by different wavelengths of light. Also, it described the development of a micelle that responded to ultrasound to localized carbon monoxide CO delivery. An introduction of metastable state photoacid is given in Chapter 1. In Chapter 2, described my work on the development of a novel mPAH, which can be activated by near infrared light is an important factor for various biological functions. mPAH was designed and synthesized with a donor-acceptor-donor structure, which increases the absorption wavelength without deactivating the photoreaction. The mPAH reversibly released a proton under 660 and 700 nm light, and effectively transferred the proton to a weak base. The reversibility, stability, reverse reaction rate, and photoreaction of them PAH were studied in detail using UV/Vis spectroscopy. In Chapter 3, a reversible mPAH switched by different wavelengths of light is described. The photo induce reverse reaction has illustrated an efficient recovery of mPAH with 22% ground state after irradiation with 365nm, in comparison to negligible thermal recovery. Reproducibility of the mPAH was confirmed after 11 cycles with switchable states using two wavelengths 470nm and 365nm without further decomposition. Well-defined photo stationary was observed at 365nm, which favor the closed form of mPAH (high acidity state). Although, the selected mPAH and yield recovery are considered not an ideal for reversible pattering application, mPAH and chlorophenol red sodium salt as indicator have demonstrated a clear reversible pattering. In Chapter 4, a micelle was developed that responded to ultrasound to localized CO delivery. The micelles consisted of a Pluronic shell and a core of Tricarbonyldichlororuthenium(II) dimer(CORM-2).The micelle released CO in the presence of cysteine. Ultrasound showed effective micelles breaking and four times the CO release without the use of ultrasound. Biological study of micelles showed a reduction in prostate cancer spread after 24 hours due to ultrasound stimulation. In Chapter 5, novels photoacid monomers and aldehydes were designed and synthesized. these works were explored and some of them showed promising results. Further work needs to be done.