Meticulous Doxorubicin Release from pH-Responsive Nanoparticles Entrapped within an Injectable Thermoresponsive Depot

Controlled Sr(ii) ion release from in situ crosslinking electroactive hydrogels with potential for the treatment of infections

The development of electrochemical stimuli-responsive drug delivery systems is of both academic and industrial interest due to the ease with which it is possible to trigger payload release, providing drug delivery in a controllable manner. Herein, the preparation of in situ forming hydrogels including electroactive polypyrrole nanoparticles (PPy-NPs) where Sr2+ ions are electrochemically loaded for electrically triggered release of Sr2+ ions is reported. The hydrogels were characterized by a variety of techniques including Fourier-transform infrared (FTIR) spectroscopy, scanning electron microscopy (SEM), energy dispersive X-ray spectroscopy (EDX), thermogravimetric analysis (TGA), X-ray diffraction (XRD), cyclic voltammetry (CV), etc. The cytocompatibility towards human mesenchymal stem cells (MSCs) and fibroblasts were also studied. The Sr2+ ion loaded PEC-ALD/CS/PPy-NPs hydrogel showed no significant cytotoxicity towards human mesenchymal stem cells (MSCs) and fibroblasts. Sr2+ ions were electrochemically loaded and released from the electroactive hydrogels, and the application of an electrical stimulus enhanced the release of Sr2+ ions from gels by ca. 2-4 fold relative to the passive release control experiment. The antibacterial activity of Sr2+ ions against E. coli and S. aureus was demonstrated in vitro. Although these prototypical examples of Sr2+ loaded electroactive gels don't release sufficient Sr2+ ions to show antibacterial activity against E. coli and S. aureus, we believe future iterations with optimised physical properties of the gels will be capable of doing so.

Triggered and monitored drug release from bifunctional hybrid nanocomposites

Polymer-coated carbon dot-containing calcium carbonate nanoparticles are reported as unique nanocomposites capable of encapsulating a chemotherapeutic drug and displaying afterglow behaviour.

Application of Non-Viral Vectors in Drug Delivery and Gene Therapy

Vectors and carriers play an indispensable role in gene therapy and drug delivery. Non-viral vectors are widely developed and applied in clinical practice due to their low immunogenicity, good biocompatibility, easy synthesis and modification, and low cost of production. This review summarized a variety of non-viral vectors and carriers including polymers, liposomes, gold nanoparticles, mesoporous silica nanoparticles and carbon nanotubes from the aspects of physicochemical characteristics, synthesis methods, functional modifications, and research applications. Notably, non-viral vectors can enhance the absorption of cargos, prolong the circulation time, improve therapeutic effects, and provide targeted delivery. Additional studies focused on recent innovation of novel synthesis techniques for vector materials. We also elaborated on the problems and future research directions in the development of non-viral vectors, which provided a theoretical basis for their broad applications.