Document Type
Dissertation
Date of Award
5-31-2020
Degree Name
Doctor of Philosophy in Chemistry - (Ph.D.)
Department
Chemistry and Environmental Science
First Advisor
Kevin D. Belfield
Second Advisor
Yuanwei Zhang
Third Advisor
Yong Ick Kim
Fourth Advisor
Mengyan Li
Fifth Advisor
Xuan Liu
Abstract
Gene theranostics have emerged as an important tool for the treatment of cancer as well as other diseases. Among the challenges in this field is the lack of effective vectors to chaperone plasmids into cells while the vector itself exhibits minimal toxicity. Herein, the synthesis, cellular uptake, and gene delivery using a biocompatible norbornene-based block copolymer is reported. This block copolymer, bearing polyethylene glycol moieties along with primary amines is functionalized with both a boron dipyrromethene (BODIPY) fluorophore for fluorescence tracking and a folic acid derivative for cancer cell targeting.
Stoichiometry control afforded residual unreacted amine functional groups available to interact with the polyanionic backbone of plasmid DNA to form polyplexes, enabling gene delivery into HeLa cells and visualization via conventional and two-photon fluorescence microscopy. Gene transfection is confirmed using a plasmid that expresses green fluorescent protein (GFP). Cell viability and transfection efficacy is assessed relative to a common vector (chaperone), Lipofectamine 2000. The functionalized norbornene block copolymer exhibited markedly less cytotoxicity than the commercial chaperone. Translation of this concept towards a gene theranostic agent and further substantiation of the novel norbornene polymer's capability to deliver plasmids into cells is demonstrated with a cytochrome c-GFP plasmid, which can induce apoptosis in vitro. Relative to untreated cells, activation of caspase-9 and caspase-3 is significantly higher in cells treated with the norbornene polymer-plasmid polyplex, indicating its effectiveness in delivering therapeutic plasmids.
Recommended Citation
Singh, Sweety, "Pegylated block copolymer for cancer imaging and treatment" (2020). Dissertations. 1783.
https://digitalcommons.njit.edu/dissertations/1783
