Detection of Hazardous Analytes Synthesis Photophysical and Photobiological Studies of Designed Fluorescent Chemodosimeters

Abstract

My thesis, named Detection of Hazardous Analytes: Synthesis, Photophysical and Photobiological Studies of Designed Fluorescent Chemodosimeters , discusses the use of a few optical sensing techniques for recognizing harmful chemicals and ions. In this thesis, I will present several newly created organic compounds for detecting certain physiologically and environmentally harmful toxic chemicals and ions even in and#956;M and nM ranges. The chemodosimeters addressed in this thesis bind to the targeted analyte extremely quickly, accompanied by a noticeable and prominent visible color change in most cases, giving them the advantage of real-time, naked-eye detection. More importantly, the constructed chemodosimeters discussed in this thesis can be used in cellular imaging research, and their applicability can also be demonstrated for the qualitative identification of these analytes using a simple, low-cost, and user-friendly experiment known as the quotdip-stick methodquot. newline newlineThe fundamental concepts of fluorescence chemosensors/chemodosimeters are covered in Chapter 1, along with an examination of a few notable studies that demonstrate how they have grown over time into a powerful and complex analytical method. newline newlineIn Chapter 2, a methoxynaphthalene benzothiazole conjugate (MNBTZ) with a C=C vinylic double bond is developed for the selective detection of CNand#8722; ions. The probe shows yellow fluorescence due to ICT from the methoxynaphthalene moiety to benzothiazole, which immediately changes to light purple upon the nucleophilic addition of CNand#8722; to the vinylic double bond, inhibiting ICT due to the break-in conjugation. The detection limit is 2.1(± 0.0022) ×10-8 M. newline newlineChapter 3 discusses a thiophene-derived biocompatible quotturn-onquot fluorescence probe (TPHZ) for detecting hypochlorite (ClOand#8722;). The fluorescence and colorimetric sensing of the probe used an ICT OFF technique. The experimental results indicated a spectacular quotturn onquot fluorescence amplification from colorless to bright blue after the addition of ClOand#8722; within 130 seconds in a