Structural Polyfluorene Derivative Nanocarriers with Promising Fluorescence Emission and Antifouling Properties

Abstract

Herein, a zwitterionic PF-based copolymer, polyfluorene-a-polybenzothiadiazole-g-polycaprolactone-b-poly[3dimethyl(methacryloxyethyl)-propaneammoniumsulfonate] [PF-a-PBTH-g-(PCL-b-PDMAPS)], was synthesized by combining multiple polymerization techniques and further quaternization. The resultant copolymer with optimized structures (P5) was able to form stabilized unimolecular micelles in an aqueous solution with a diameter of approximately 110 nm. The unique donor− acceptor structure between fluorene and benzothiadiazole group along the conjugated main chains endows copolymers with yellowgreen fluorescence, while the PDMAPS chains with a unique zwitterionic nature enabled not only to enhance water solubility, drug loading efficiency (DLE), and drug loading capacity (DLC) of the whole copolymers but also to present promising antifouling property by preventing nonspecific protein/bacteria adhesion. Further in vivo and in vitro experiments demonstrate that the resultant P5 micelles also present lower cytotoxicity and efficient cellular uptake with the incubation of HeLa and HUVEC cells, which tends to prolong the circulation time of drugs. Our work not only provides a rational combination of zwitterions and polyfluorenes to significantly enhance the water solubility of hydrophobic fluorophores but also exhibits the potential of promising bioimaging for dual stimuli-responsive micelles in vitro (simulated body fluids) and in vivo (open).

Preparation of a Fluorescent Polymer Sensing System with an Oxidation-Electric Dual-Mode Response Based on the Supramolecular Host–Guest Interaction

“…Polymer fluorescent probes not only maintain the properties of small monomers but also exhibit unique properties due to the polymeric synergistic effect . Our group has constructed several fluorescent sensing systems for biomedical applications utilizing polymers as backbones. − The fluorescent sensing systems that utilize polymers as backbones have overcome the issues of easy aggregation, light scattering interference, and photobleaching of individual dye molecules in various applications. , These systems have shown high binding constants, detection sensitivity, photostability, ease of modification, biocompatibility, and multitarget detection. − …”

Unimolecular micelles from star-shaped block polymers by photocontrolled BIT-RDRP for PTT/PDT synergistic therapy

“…In recent years, the application of UIMs in tumor therapy has received increasing attention due to their excellent stability in the microenvironment of living organisms and unexpected effects through the enhanced permeability and retention effect of solid tumors. 25,26 A variety of studies have been conducted to show their excellent performance in drug delivery, 27 in vivo imaging, 28 chemotherapy, 29 photothermal therapy, 30 photodynamic therapy 31 and so on. Compared with traditional chemotherapy and radiotherapy, photothermal therapy (PTT) and photodynamic therapy (PDT) are two minimally invasive, highly effective optical therapies with few side effects, which have become a hot research spot in the field of tumor treatment.…”

“…21,22 The unique assembly behavior makes it easier to escape from the capture of the immune system and reach the lesion site, and to maintain long-lasting potency in the complex and variable microenvironment in vivo. [23][24][25] Therefore, UIMs with multifunctions through convenient preparation state show highly promising applications in the medical field.…”

A Multiple-Responsive Fluorescence Probe Based on Water-Soluble Fluorescent Conjugated Polymer for Biomolecules Detection

“…Nowadays, owing to stable chemical structures, high quantum efficiency, and reliable performance, a fluorescent probe based on fluorescent conjugated polymers (FCPs) has become one of the focuses of researchers. However, due to the limitations of the extremely poor water solubility of FCP, most of the probe polymer molecules used to detect water-based samples need to undergo necessary water-soluble modification, − which often affects the substrate responsiveness dependent on special functional groups, thus reducing the detection ability. Therefore, reasonably adjusting the molecular structure to obtain water solubility while retaining high sensitivity as much as possible is the key to designing polymer fluorescent probes.…”