The interface between a biofilm and the underlying substrate to which it is attached is challenging to study. Currently, available methods of studying this microenvironment have not been able to record data in real-time over a time period in the range of days. To address this challenge, we report the...
The general theme of this dissertation is the development of new analytical sensors to quantitatively study biological and environmental samples in aqueous and non-aqueous environments. A platinum ultramicroelectrode (UME) and a unique carbon-based pH microprobe were used to design a new SECM-based electrochemical bioassay. The Pt UME was used to...
The structural architecture present in marine toxin azaspiracid - 20 stereocenters, 9 rings, 3 separated spirocenters - has attracted considerable synthetic attention. Our efforts toward the synthesis of azaspiracid have led to the completion of both C₁-C₂₆ northern and C₂₇-C₄₀ southern halves. Herein, the
synthesis of southern FGHI ring system...
Azaspiracid has generated an enormous amount of scientific interest in the fourteen years since its initial discovery. The structure contains a 6,5,6 bis-spiroketal, a [3.3.1] bicyclic ketal and a 6,5-spiroaminal linkage as key moieties. With 9 rings, 20 stereocenters and three alkenes, the azaspiracid immediately attracted the interest of the...
Polycyclic aromatic hydrocarbons (PAHs) are a group of environmental contaminants consisting of fused benzene rings. Parent-PAHs, methylated-PAHs (MPAHs), and PAHs with molecular weight of 302 a.m.u (MW302-PAHs) are considered as unsubstituted-PAHs. These unsubstituted-PAHs undergo transformation reactions resulting in the formation of PAH-transformation products (PAH-TPs), or substituted-PAHs, including nitrated-, oxygenated-, and...
Structure-property relationships have always underpinned the field of solid state chemistry; dependable structural descriptions are integral to understanding and controlling the physical properties of inorganic compounds old and new. While a handful of crystal structures are celebrated for their versatility, flexibility, and functionality, the existence of more exotic structures is...
Femtosecond stimulated Raman spectroscopy (FSRS) is an ultrafast vibrational technique which allows rapid collection of Raman spectra with simultaneously high temporal and spectral resolution. With the recent development of FSRS methodology, three FSRS techniques (conventional, tunable, and anti-Stokes) have been implemented in our laboratory to dissect the excited state structural...