A versatile method for generating semiconducting polymer dot nanocomposites

Abstract

This paper describes a method, based on co-precipitation, for generating small semiconducting polymer dot (Pdot) nanocomposites, which contain either gold or iron oxide nanoparticles within the Pdot matrix. We demonstrate the utility of Pdot-Au nanoparticles (Au-NP-Pdots) in dual-modality imaging in which co-localization of fluorescence from Pdot and scattering from Au was used to identify Au-NP-Pdot probes for downstream single-particle tracking and cellular imaging. We also demonstrate the potential of employing Pdot-FeOx nanoparticles (FeOx-NP-Pdots) for both sample preparation, where cells tagged with FeOx-NP-Pdots were isolated using an external magnet, and cellular imaging and detection, owing to the intense fluorescence from Pdots. The method we present here should be generalizable to the formation of other Pdot nanocomposites for creating the next generation of multi-functional Pdot probes.

Highly Fluorescent Semiconducting Polymer Dots for Biology and Medicine

“…[40–44] There have been significant efforts to create versatile semiconducting polymer nanoparticles (a small subset of which are Pdots), tune their properties and functions, and improve their performance for biomedical studies. The research efforts include exploring new preparation methods, [45,46,69,70,72] investigating nanoparticle formation mechanisms, [120,121] probing nanoparticle photophysics, [47,49,54,122,123] characterizing the fluorescence performance, [48,51,56,58] tuning the emission color, [47,49,71,89] engineering the particle surface, [56–58,64–66,98,102] encapsulating inorganic materials, [96,97,99,104,105] developing nanoparticle sensors, [52,59,60,62,74,77] imaging cellular structures, [56,57,63–66] and in vivo targeting in small animals. [58,72] …”

“…For example, semiconducting polymer nanoparticles can be prepared from hydrophobic semiconducting polymers, [45–80] polyelectrolytes, or hydrophilic polymers, [81–88] as self-assembled nanoparticles from amphiphilic polymers, [89–93] as hydrophobic semiconducting polymer-loaded poly(D, L-lactide- co -glycolide) (PLGA) particles, [94–97] as phospholipid-encapsulated or PEG-capped hydrophobic polymer nanoparticles, [98–102] and as semiconducting polymer-coated inorganic nanoparticles. [103–105] Among these nanoparticles, the fluorescence, colloidal stability, and functional performance are highly dependent on their particle size, composition, internal structure, and surface properties.…”

Mind your P's and Q's: the coming of age of semiconducting polymer dots and semiconductor quantum dots in biological applications

“…In each case, Pdots act as antennae that absorb excitation light and efficiently transfer the excitonic energy to the dopant emitters, increasing their apparent brightness. Other dopants have included photochromic spiropyran dyes to generate photoswitchable Pdots that may be useful for super-resolution imaging [70], gold NPs to provide both dark-field and fluorescence contrast [71], and iron oxide NPs to enable magnetic manipulation [71].…”

Near-Infrared Fluorescent Semiconducting Polymer Dots with High Brightness and Pronounced Effect of Positioning Alkyl Chains on the Comonomers

“…6,[33][34][35][36][37][38][39][40][41][42][43][44][45][46] Despite the enormous progress, the synthesis of suitable NIR fluorescent semiconducting polymers for generating Pdots is still a significant challenge, partially because of the rigid and flat extended -conjugated skeletons of NIR polymers that result in the serious self-quenching upon condensation into a Pdot form. 47-51 Accordingly, there have been several approaches developed to address the aforementioned challenge.…”