pH‐responsive near‐infrared emitting conjugated polymer nanoparticles for cellular imaging and controlled‐drug delivery

Abstract

In this article, pH-responsive near-infrared emitting conjugated polymer nanoparticles (CPNs) are prepared, characterized, and their stabilities are investigated under various conditions. These nanoparticles have capacity to be loaded with water insoluble, anticancer drug, camptothecin (CPT), with around 10% drug loading efficiency. The in vitro release studies demonstrate that the release of CPTs from CPNs is pHdependent such that significantly faster drug release at mildly acidic pH of 5.0 compared with physiological pH 7.4 is observed. Time and dose-dependent in vitro cytotoxicity tests of blank and CPT-loaded nanoparticles are performed by realtime cell electronic sensing (RT-CES) assay with hepatocellular carcinoma cells (Huh7). The results indicate that CPNs can be effectively utilized as vehicles for pH-triggered release of anticancer drugs.

Smart multifunctional nanoparticles in nanomedicine

“…Furthermore, multifunctional nanoparticles with simultaneously useful capabilities such as targeting and imaging contrast enhancement can be synthesized. These nanoparticles combine both diagnostic and therapeutic features within a single formulation and therefore are denoted as "theranostic" agents [72][73][74]. Despite the fact that there are several nanoparticle based drug delivery systems, being developed or being currently under preclinical and/or clinical evaluation, still only a few such nano-drugs are in use on the market [75].…”

Polymeric nanoparticles: the future of nanomedicine

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Recent advances in cell imaging and cytotoxicity of intracellular stimuli-responsive nanomaterials

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