Author ORCID Identifier
0000-0003-2829-2570
Biosketch
Sasikala R received her Bachelor’s and Master’s degrees in Chemistry from Seethalakshmi Ramaswami College (2014–2019). She qualified the Graduate Aptitude Test in Engineering (GATE) in 2020 and joined the School of Chemical & Biotechnology, SASTRA Deemed University, as a Junior Research Fellow.She conducted her doctoral research on organic luminescent materials at SASTRA University under the supervision of Prof. Philip Anthony.
Her research focuses on the design, synthesis, and photophysical characterization of small organic molecules exhibiting stimuli-responsive fluorescence, including ion sensing and environmental responsiveness.Her work involves the development of advanced organic fluorescent materials with multi-stimuli responsiveness, dual-state emission, and application-oriented sensing properties. She has designed and synthesized a diverse library of triphenylamine-based, ionic, zwitterionic, and heterocyclic fluorophores with tunable photophysical characteristics, demonstrating applications in chemical sensing, mechanochromism, bioimaging and security technologies.In addition, she reported anion-dependent tunable red-emitting ionic fluorophores exhibiting fluorescence tuning, solvent discrimination, white-light emission, and latent fingerprinting capabilities.
Her work also includes dual-state emissive donor–acceptor fluorophores with self-reversible mechanofluorochromism and propeller-shaped triarylamine acids serving as ultra-sensitive probes for isomer and water sensing.She has published over 35 peer-reviewed international research articles and has made significant contributions to the development of novel luminescent molecules and stimuli-responsive systems relevant to advanced functional materials and high-technology applications.
Date of Award
22-7-2025
Document Type
Thesis
School
School of Chemical & Biotechnology
Programme
Ph.D.-Doctoral of Philosophy
First Advisor
S.Philip Anthony
Keywords
Organic Solid state Fluorescence, Stimuli-Responsive Materials, Aggregation Induced Emission, Triarylamine Luminophores, Latent Fingerprinting
Abstract
Organic solid-state fluorescent materials have garnered attention over many decades in virtue of their contribution in the development of LED devices and biomedical applications. Nevertheless, the potential of fluorescent molecules in device applications was underused due to aggregation-caused quenching (ACQ) effect. The ACQ effect commonly quenches the organic molecules fluorescence intensity in the aggregated or condensed state, which can significantly influence their performance in practical applications.
The organic polyaromatic fluorophores exhibit strong fluorescence in the solution state. After culmination of years of work, Prof. Tang’s research group discovered a new phenomenon of aggregation-induced emission (AIE) in the fluorescence molecules constructed using the twisted propeller units. Converse to ACQ, the aggregation light-up or enhanced the emission in the condensed or aggregated state, which are generally non-emissive/weakly emissive in solution state.
The development of conformationally flexible triarylamine based donor-π-acceptor (D-π-A) motif with excellent photophysical and optical characteristics is of great demand owing to their practical utility in optoelectronics, organic field effect transistor, chemo-sensors and displayes. Stimuli-responsive material exhibits fluorescence switching and tuning in response to external stimuli such as pressure, temperature, light, pH and vapours thereby influencing molecular packing and weak intermolecular interactions. The conformationally twisted molecules displaying strong solid-state fluorescence along xx with stimuli responsive fluorescence switching behaviour are suitable for the development of molecular switches and sensors. Herein, we have developed carbazole integrated multistimuli responsive materials with subtle structural variation and explored the impact of structural variation on the fluorescence properties and stimuli-responsive fluorescence switching.
To circumvent ACQ and hydrophobicity issues, the charged AIEgens was inherited and benefitted better optical, forensic and biological applications. We have developed triarylamines based ionic fluorophores with distinct noteworthy tunable emission while susceptible to external stimuli. The ionic fluorophores by quarternizing pyridine nitrogen of varied chain length was synthesized in order to study the influence of molecular assembly in solid state emission. The hydrophobic longer alkyl chain was successfully utilized for lighting up latent finger prints with level 3 information on porous and non- porous surfaces.
Recommended Citation
R, Sasikala Ms, "Design and Investigation of Triarylamine Functionalized Luminophores for Multi-Functional and Stimuli-Responsive Applications" (2025). Theses and Dissertations. 165.
https://knowledgeconnect.sastra.edu/theses/165