A smart polymer for drug delivery sensitive to tumor extracellular pH

Modified PLGA-PEG-PLGA thermosensitive hydrogels with suitable thermosensitivity and properties for use in a drug delivery system

PLGA-PEG-PLGA (PPP) triblock copolymer is the most widely studied thermosensitive hydrogel owing to its non-toxic, biocompatible, biodegradable, and thermosensitive properties. PPP thermosensitive hydrogels are being investigated as in situ gels because, at a low temperature, PPP solutions with drugs can be injected at the target site, and converted into a gel without surgical procedures. To meet the requirements of different therapeutic applications, PPP hydrogels with different properties need to be synthesized. The adjustable properties include the sol-gel transition temperature, gel window width, retention time and drug release time. Furthermore, thermo- and pH-, thermo- and electro-, and thermo- and photo-dual sensitive hydrogels are needed for some special therapies. Thus, this review examines the methods of modification of PPP thermosensitive hydrogels used to obtain desired drug delivery systems with appropriate physicochemical and pharmaceutical properties.

Stimuli-responsive nanogel composites and their application in nanomedicine

Nanogels are nanosized crosslinked polymer networks capable of absorbing large quantities of water. Specifically, smart nanogels are interesting because of their ability to respond to biomedically relevant changes like pH, temperature, etc. In the last few decades, hybrid nanogels or composites have been developed to overcome the ever increasing demand for new materials in this field. In this context, a hybrid refers to nanogels combined with different polymers and/or with nanoparticles such as plasmonic, magnetic, and carbonaceous nanoparticles, among others. Research activities are focused nowadays on using multifunctional hybrid nanogels in nanomedicine, not only as drug carriers but also as imaging and theranostic agents. In this review, we will describe nanogels, particularly in the form of composites or hybrids applied in nanomedicine.

A DT-diaphorase responsive theranostic prodrug for diagnosis, drug release monitoring and therapy

A DT-diaphorase responsive theranostic prodrug has been developed for diagnosis, tracking of drug release and selectively killing cancer cells over-expressed with DT-diaphorase.