Stimulus-responsive fluorescent nanoparticles for theragnosis

Abstract

Stimulus-responsive material architectures can empower medical therapies by bio-imaging for diagnosis, destruction of cells for cancer therapy and controlling release of drug in response to selective biological recognition events. In this thesis, we have discussed three components

one is pH and light responsive polymer integrated fluorophore with graphene oxide (in chapter 2-3), the next one is biocompatible delivery (in chapter 4) and the last one is carbonized fluorescence nanoparticles (in chapter 5-6). In chapter 2, we report a stimuli responsive fluorescence nano-material based on graphene oxide with photochromic dye spiropyran (SP) and hydrophobic dye BODIPY conjugated polymer, for triggered target multi-color bioimaging application. Then, we have synthesized a pH-dependent, NIR-sensitive, reduced graphene oxide (rGO) hybrid nano-composite via electrostatic interaction with indocyanine green (ICG) which is designed not only to destroy localized cancer cells but also be minimally invasive to surrounding normal cells (chapter 3). We also report on dopamine-conjugated hyaluronic acid (HA-D), a mussel-inspired facile capping material that can modify tungsten oxide $(WO_3)$ nanoparticles to be both biocompatible and targetable, allowing precise delivery $(WO_3-HA)$ to a tumor site for photothermal therapy (chapter 4). In chapter 5, we describes the in situ synthesis of single fluorescence carbon nanoparticles (FCNs) for target bioimaging applications derived from biocompatible hyaluronic acid (HA) without using common conjugation processes. The converted nanocrystal carbon particles from HA provide outstanding features for in vitro and in vivo new targeted delivery and diagnostic tools. In last chapter, we report the development of cooperative drug delivery systems that can detect and target the disease site, with an environment sensitive (pH), and external photothermally remote controlled, cooperative image-guided drug delivery matrix. Cooperative guided bioimaging that employs both internal pH responsive and external NIR controlled drug carriers is a promising method for chemotherapeutic release that can be adjusted according to physiological needs.