Confined microemulsion sono-polymerization of poly(ethylene glycol) nanoparticles for targeted delivery

Engineering poly(ethylene glycol) particles for targeted drug delivery

Poly(ethylene glycol) (PEG) is considered to be the "gold standard" among the stealth polymers employed for drug delivery. Using PEG to modify or engineer particles has thus gained increasing interest because of the ability to prolong blood circulation time and reduce nonspecific biodistribution of particles in vivo, owing to the low fouling and stealth properties of PEG. In addition, endowing PEG-based particles with targeting and drug-loading properties is essential to achieve enhanced drug accumulation at target sites in vivo. In this feature article, we focus on recent work on the synthesis of PEG particles, in which PEG is the main component in the particles. We highlight different synthesis methods used to generate PEG particles, the influence of the physiochemical properties of PEG particles on their stealth and targeting properties, and the application of PEG particles in targeted drug delivery.

Surface-engineered nanoparticles in cancer immune response and immunotherapy: Current status and future prospects

Cancer immunotherapy is a therapeutic strategy to inhibit tumor growth and metastasis by intervening in the immune response process. Strategies applied to cancer immunotherapy mainly include blocking immune checkpoints, adoptive transfer of engineered immune cells, cytokine therapy, cancer vaccines, and oncolytic virus infection. However, many factors, such as off-target side effects, immunosuppressive cell infiltration and/or upregulation of immune checkpoint expression, cancer cell heterogeneity, and lack of antigen presentation, affect the therapeutic effect of immunotherapy on cancer. To improve the efficacy of targeted immunotherapy and reduce off-target effects, over the past two decades, nanoparticle delivery platforms have been increasingly used in tumor immunotherapy. However, nanoparticles are still subject to biological barriers and biodistribution challenges, which limit their overall clinical potential. This has prompted a series of engineered nanoparticles to overcome specific obstacles and transfer the accumulation of payloads to tumor-infiltrating immune cells. In recent years, new techniques and chemical methods have been employed to modify or functionalize the surfaces of nanoparticles. This review discusses the recent progress of surface-engineered nanoparticles in inducing tumor immune responses and immunotherapy, as well as future directions for the development of next-generation nanomedicines.

Sticktight-inspired PEGylation for low-fouling coatings

Polyethylene glycol (PEG) has been widely used for modifying surfaces to reduce non-specific interactions with biomolecules, microorganisms, and cells. Herein, we report a sticktight-inspired PEGylation strategy to fabricate low-fouling coatings. The influence of PEG molecular architectures on the PEG density and biological adhesion were studied. Notably, an increase in the number of arms resulted in improved surface PEGylation and an improved antifouling ability against the adhesion of proteins, mammalian cells and bacteria. The molecular architecture-dependent PEGylation strategy is an attractive approach for developing advanced low-fouling coatings.