Electroactive Polypyrrole Nanowire Arrays: Synergistic Effect of Cancer Treatment by On-Demand Drug Release and Photothermal Therapy

Abstract

An electroresponsive drug release system based on polypyrrole (Ppy) nanowires was developed to induce the local delivery of anticancer drug, doxorubicin (DOX), according to the applied electric field. DOX-conjugated Ppy nanowire (NW) (DOX/Ppy NW) array was initially prepared by electrochemical deposition of a mixture of pyrrole monomers and biotin as dopants in the anodic alumina oxide membrane as a sacrificial template. Morphological observation by scanning electron microscopy revealed free-standing and 3D nanotopographical features with large surface area and high density. In addition, we investigated the antitumor efficacy of DOX released from DOX/Ppy NW array in response to the external electric field using two kinds of cancer cell lines, human oral squamous carcinoma cells (KB cells) and human breast cancer cells (MCF7 cells). Meanwhile, strong photothermal effect as a result of a near-infrared absorbing ability of Ppy synergistically maximizes the chemotherapeutic efficacy. Our results suggested that the proposed multifunctional Ppy platform possessing several beneficial features is very promising for many therapeutic applications including cancer.

The incorporation and controlled release of dopamine from a sulfonated β–cyclodextrin–doped conducting polymer

“…While an increase in polymer thickness generally gives rise to an increase in the concentration of the drug released, thicker polymer films tend to become less electroactive. More recent attempts to increase the loading and concentration of the drug, include increasing the surface area of the polymer [8] by forming various polymer nanostructures [9,10], polymer nanoparticles/particles [11][12][13] or nanowires [14], fibres [15,16], nanotubes [17] and reservoirs that can be used to load the drug [18].…”

“…In terms of a comparison between polypyrrole and other drug delivery materials, polypyrrole is not biodegradable and while it can be formed as nanowires, nanoparticles and nanotubes [11][12][13][14][15][16][17], it is not suitable as a carrier to deliver drugs to specific sites in the body. For these applications biodegradable polymer nanogels [26,27] are attracting considerable interest as they have the potential to deliver drugs to the target cells.…”

Electrically Controlled Biochemical Release from Micro/Nanostructures for in vitro and in vivo Applications: A Review

“…The PPy‐based nanowires could be precisely transported and assembled on microelectrodes by a magnetic field, or get collected on the sharp tip of a gold‐coated micropipet with an external electric field, both of which realized localized release of ATP molecules at specific locations. More recently, an electro‐responsive drug release system based on PPy nanowire arrays was developed . As shown in Figure G, the biotin‐doped PPy nanowires provided a large number of active sites for loading the anticancer drug, doxorubicin (DOX), offering more than ten‐time greater drug‐loading capacity compared to that of conventional flat PPy films.…”

Polypyrrole Nanofibers with Extended 1D Hierarchical Structure

“…Polypyrrole nanofibers deposited on titanium(IV) oxide or combined with silver nanoparticles have been examined as photoanode materials. Polymer nanofibers have also been used for controlled drug release,, for water deionization, and in triboelectric nanogenerators (TENG) …”

“…There are a few methods to synthesize polypyrrole nanostructures. The most common ones utilize hard templates made of titanium (IV) or aluminum(III) oxides ,,,,. The templates are usually obtained by the anodic oxidation of titanium or aluminum plates followed by the deposition of a thin Au film evaporated at the oxide surface and the subsequent electropolymerization of pyrrole in the nanopores of the oxide substrate, which results in polymer nanofibers.…”