Fluorescent Indicators for Disease Biomarkers

Abstract

Table 2.1 Selected aldehyde functionalized fluorescent probes based on thiol cyclization…………………………………………………………………10 vii LIST OF FIGURES 1.1 Chapter 2 describes the selective detection of Cys via an -unsaturated aldehyde-appended fluorescein derivative………………………………………...2 1.2 Chapter 3 describes multidimensional data analysis and its application to multianalyte detection via a single indicator……………………………………...3 1.3 Chapter 4 describes the selective detection of AICAr directly in human urine without sample processing, towards the development of a practical assay for ADSL deficiency………………………………………………………………….4 2.1 Some common biological thiols…………………………………………………...5 2.2 DNBS cleavage type fluorescent probes…………………………………………..7 2.3 Some dimaleimide derivative probes and a ketocoumarin derivative……….……7 2.4 Squaraine derivative probes……………………………………………………….8 2.5 p-dimethylaminocinnamaldehyde………………………………………………..11 2.6 1 H-NMR spectra vs. times in 0.1M pH 7.4 phosphate buffer/D 2 O 9:1………….13 2.7 Absorption of 2.1 ( 501 =46981 cm-1 M-1 in 0.1 M phosphate buffer pH 7.4)……14 2.8 Absorption of 2.1 as a function of pH……………………………………………14 2.9 Spectral properties of fluorescein and compound 2.1 (2.31 × 10-6 M in 0.1 M phosphate buffer pH 7.4) in absence and presence of Cys (10.0 mM)…………..16 2.10 Spectral properties of compound 2.1 (9.38 × 10-7 M) in the presence of Cys (10.0 mM)……………………………………………………………………………....17 2.11 Response of compound 2.1 to thiols (10.0 mM) of interest and their structural analogs…………………………………………………………………………...19 2.12 Selectivity towards Cys over Hcy………………………………………………..20 2.13 Energy-minimized structures of the reaction products of 2.1 with Cys and Hcy showing the distance between the NH 3 + and the phenolate groups……………...20 2.14 Response of compound 2.1 to thiols (0.5 mM) and peptides (0.5 mM) of interest…………………………………………………………………………....23 viii 3.1 Rhodamine boronic acid 3.1 and ribose and ribose-containing target molecules………………………………………………………………………...28 3.2 Energy-minimized model of the boronate ester formed after condensation of one equivalent of a nucleoside (AICAr) to 3.1……………………………………….29 3.3 Emission spectra demonstrating selective response to various analytes………...31 3.4 Intensity as a function of time……………………………………………………32 3.5 EEMs demonstrating the response of 3.1 towards various analytes……………..34 3.6 Time and wavelength dependent detection………………………………………36 4.1 ADSL deficiency biomarker SAICAr and S-Ado……………………………….42 4.2 Rhodamine boronic acid 3.1 and AICAr………………………………………...44 4.3 EEMs and emission spectra demonstrating the responses of 3.1 to AICAr at 8 min after mixing in a simple 10% buffer: 90% DMSO solvent system………………45 4.4 EEMs and emission spectra demonstrating the responses of 3.1 to AICAr at 20 min after mixing in 5% healthy human urine: 5% buffer: 90% DMSO………....47 ix LIST OF ABBREVIATIONS